Medtronic ADDR01, ADDRS1, ADDR03, ADDR06, ADDRL1 Pacemaker Reference Manual

...

ADAPTA®/VERSA®/SENSIA®/ RELIA™

Adapta ADDR01/03/06 Adapta S ADDRS1 Adapta L ADDRL1 Adapta ADD01 Adapta ADVDD01 Adapta ADSR01/03/06 Versa VEDR01 Sensia SEDR01 Sensia L SEDRL1 Sensia SED01 Sensia SESR01 Sensia SES01 Relia REDR01 Relia RED01 Relia RESR01 Relia RES01 Relia REVDD01

Pacemaker Reference Guide

Contents

How to use this guide 9

1 Pacing modes 13

Introduction 14

Rationale for mode selection 15

Indications 17

Contraindications 17

MVP modes 18

DDDR mode 18

DDD mode 20

DDIR mode 21

DDI mode 22

DVIR mode 23

DVI mode 24

VDD mode 25

AAIR / ADIR modes 26

AAI / ADI modes 27

VVIR / VDIR modes 28

VVI / VDI modes 29

AAT / VVT modes 30

DOOR / AOOR / VOOR modes 31

DOO / AOO / VOO modes 32

ODO / OAO / OVO modes 33

2 Rate response 35

Introduction to rate responsive pacing 36

Preset rate response at implant 37

Rate Profile Optimization operation 39

Individualizing Rate Profile Optimization 46

Activity sensor operation 48

Manual control of Rate Profile Optimization 53

3 Pacemaker timing 55

Rates 56

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Contents

AV intervals 63

Rate Adaptive AV 66

Search AV+ and diagnostic 69

Blanking periods 73

Refractory periods 75

High rate atrial tracking 84

4 Lead/cardiac tissue interface 87

Implant Detection 88

Automatic polarity configuration 89

Lead Monitor 94

Lead impedance data 97

Capture Management and diagnostic 98

Sensing Assurance and diagnostic 118

Manually selecting pacing parameters 122

Manually selecting sensing parameters 125

Transtelephonic follow-up features 129

5 Special therapy options 133

Mode Switch and diagnostic 134

Managed Ventricular Pacing (MVP) 142

Conducted AF Response 147

Non-competitive atrial pacing 148

PMT intervention 150

PVC Response 153

Ventricular Safety Pacing 155

Sinus Preference 156

Atrial Preference Pacing 160

Rate Drop Response and diagnostic 164

Sleep Function 171

Single Chamber Hysteresis 173

6 Telemetry data 175

Establishing telemetry 176

Parameter summary 176

Patient information 178

Using TherapyGuide to select parameter values 179

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Battery and lead information 181

Marker Channel telemetry 182

Intracardiac electrograms 184

Extended Telemetry 186

7 Miscellaneous operations 187

Magnet Mode operation 188

Temporary programming 190

Electrical reset 191

Recommended Replacement Time (RRT/ERI) 193

Emergency pacing 194

8 Diagnostics 195

Introduction to diagnostics 196

Heart Rate Histograms 200

AV Conduction Histograms 202

Search AV+ Histogram 204

Sensor Indicated Rate Profile 205

High Rate Episodes 206

Ventricular Rate Histogram During Atrial Arrhythmias 213

Atrial Arrhythmia Trend 214

Atrial Arrhythmia Durations 216

Custom Rate Trend 216

Key Parameter History 219

Contents

9 Troubleshooting the pacing system 221

Troubleshooting strategy 222

Troubleshooting electrical problems 223

Troubleshooting hemodynamic problems 226

A Pacemaker description 231

Model number designator 232

Radiopaque codes 233

Physical dimensions 234

Connector dimensions 235

B Preset parameter settings 237

Shipping and nominal settings 238

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Contents

Electrical reset settings 251

Emergency settings 263

C Longevity projections 265

Projected service life 266

Prolonged service period 282

Recommended Replacement Time (RRT/ERI) 282

Battery specifications 283

D Telemetry and diagnostic values 285

Magnet Mode operations 286

Telemetry functions 287

Automatic diagnostics 290

Clinician-selectable diagnostics 292

Cardiac event counters 297

E Parameter values and restrictions 299

Programmable modes and parameters 300

Rate Response programming guidelines 315

F Implant information 317

Warnings 318

Precautions 320

Potential complications 328

Replace a device 329

Patient counseling information 330

G Glossary 333

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Adapta/Versa/Sensia/Relia 0

Pacemaker Reference Guide 0

A guide to the Adapta/Versa/Sensia/Relia pacemakers

Refer to the Adapta/Versa/Sensia/Relia Pacemaker Programming Guide for information on software and programming.

The following are trademarks of Medtronic: Adapta, Checklist, Find Patient, Marker Channel, Medtronic, Medtronic Carelink, MVP,

Quick Look, Relia, Search AV, Sensia, SessionSync, TherapyGuide, and Versa.

How to use this guide

Information is contained in two guides

Product information about Adapta/Versa/Sensia/Relia pacemakers and the associated software for the 9790/C series programmer and the 2090 programmer is presented in two separate guides.

The Pacemaker Reference Guide (PRG) provides detailed information on the pacemakers.

The Pacemaker Programming Guide (PPG) contains instructions on how to use the programmer and the programming software.

About the Pacemaker Reference Guide

The Pacemaker Reference Guide describes in detail how the pacemakers operate and specifies the capabilities of the pacemakers. The PRG includes the following information:

■

Describes the pacing modes, rate response options, special therapy features, telemetry types, and data collection options. In some cases, guidelines are given on how to configure the pacemaker operation.

■

Contains troubleshooting information for electrical and hemodynamic problems.

■

Specifies parameter and data collection capabilities, longevity projections, and mechanical and electrical specifications.

■

Provides general warnings and cautions, potential interference sources, and general indications for pacing.

■

Contains a glossary of terms.

How to use this guide

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

How to use this guide

About the Pacemaker Programming Guide

The Pacemaker Programming Guide describes how to program Adapta, Versa, Sensia, and Relia pacemakers using a programmer. The PPG presents the following information:

■

How to set up and configure the programmer and access online help.

■

How to start a patient session, use the various follow-up features during the session, and properly end the session.

■

How to use Checklist to streamline a follow-up session.

■

How to view and print the patient’s ECG and EGM waveform traces.

■

How to configure the pacemaker to collect diagnostic data and how to retrieve and view this information.

■

How to measure stimulation thresholds and sensing levels.

■

How to use TherapyGuide to obtain suggested parameter values.

■

How to program parameter values and verify rate response parameters settings.

■

How to run EP Studies.

The Implant Manuals supplement these guides

For each pacemaker model in the Adapta/Versa/Sensia/Relia family, there is an Implant Manual. The Pacemaker Programming Guide and the Pacemaker Reference Guide do not specify which features apply to each individual pacemaker model. Refer to the applicable implant manual for specific capabilities of individual models.

Also, in various places throughout this manual, for example “Programmable modes and parameters” on page 300, you are asked to refer to the applicable implant manual for specific capabilities of individual models

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

How to use this guide

New nomenclature for product battery life terms

This manual uses a new nomenclature for certain terms related to product battery life. This new nomenclature is defined in CENELEC pacemaker standard EN 45502-2-1:2003, which applies to Active Implantable Medical Devices (AIMD) intended to treat bradyarrhythmias. This standard was approved and published in December 2003.

Medtronic has adopted the new nomenclature to comply with the CENELEC standard and in anticipation of the nomenclature becoming an international standard.

The new nomenclature, and the terms replaced by the new nomenclature, are presented in the following table:

New nomenclature Old nomenclature

BOS Beginning of Service BOL Beginning of Life

EOS End of Service EOL End of Life

RRT/ERI Recommended

Replacement Time (RRT/ERI)

Prolonged service period

Projected service life Longevity

ERI Elective Replacement

Post-ERI conditions

Indicator

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Introduction 14

Rationale for mode selection 15

Indications 17

Contraindications 17

MVP modes 18

DDDR mode 18

DDD mode 20

DDIR mode 21

DDI mode 22

DVIR mode 23

DVI mode 24

VDD mode 25

Pacing modes1

AAIR / ADIR modes 26

AAI / ADI modes 27

VVIR / VDIR modes 28

VVI / VDI modes 29

AAT / VVT modes 30

DOOR / AOOR / VOOR modes 31

DOO / AOO / VOO modes 32

ODO / OAO / OVO modes 33

Chapter 1

Introduction

Pacing mode selection

This chapter provides an introduction to pacemaker modes as an aid to pacing mode selection. The chapter is organized as follows:

Definition of basic pacing modes – The names for most of the pacing modes are defined on the 1991 ACC/AHA guidelines for pacemaker implantation.

Rationale for mode selection – In order to get pacing mode suggestions, the use of TherapyGuide is recommended. TherapyGuide is a programmer feature that suggests parameter settings based on a patient's clinical conditions. For models which do not contain TherapyGuide, refer to the device implant manual for guidance in mode selection.

Mode descriptions – These descriptions provide indications and contraindications for modes available with the pacemaker and brief descriptions of how these modes operate.

NBG pacing codes

The pacemaker modes are defined in NBG Code.2 Each five-letter NBG code describes a specific type of operation for implantable pacemakers. For simplicity, this manual uses only the first three or four letters, such as DDD, DDIR, DVIR, and so forth. Figure 1-1 describes the first four letters of the NBG code.

Dreifus LS, Fisch C, Griffin JC, et al. Guidelines for implantation of cardiac pacemakers and antiarrhythmia devices. A report of the American College of Cardiology/American Heart Association Task Force on Assessment of Diagnostic and Therapeutic Cardiovascular Procedures (Committee on Pacemaker Implantation). Journal of the American College of Cardiology. 1991; 18: 1-13.

Bernstein A., et al., “The NASPE/BPEG Pacemaker Code,” PACE, 10(4), Jul-Aug 1987. (“NBG” stands for The North American Society of Pacing and Electrophysiology [NASPE] and the British Pacing and Electrophysiology Group [BPEG] Generic. NBG’s five-letter code supersedes the ICHD Code.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Pacing modes

Rationale for mode selection

Further information

CHAMBER PACED

V = Ventricle

A = Atrium

D = Dual Chamber

S = Single Chamber

O = None

CHAMBER SENSED

V = Ventricle

A = Atrium

D = Dual Chamber

S = Single Chamber

O = None

Figure 1-1. NBG pacing codes

DDDR

MODE OF RESPONSE

T = Triggered

I = Inhibited

D = Double (Both)

O = None

PROGRAMMABLE/ RATE RESPONSE

P = Programmable

M = Multiprogrammable

C = Communicating

R = Rate Responsive

O = None

The mode descriptions in this chapter provide only a basic overview of each mode. For further details on the rate response, timing, and therapy capabilities, refer to “Rate response” on page 36, “Pacemaker timing” on page 55, and “Special therapy options” on page 133.

Rationale for mode selection

TherapyGuide offers a simple clinically-focused method for a clinician to obtain suggested parameter values. At implant or an early follow-up appointment, the clinician enters information about the patient's clinical conditions. Based on those inputs the programmer suggests parameter settings. The suggestions are based on clinical studies, literature, current practice, and the consensus of physicians.

For more information about TherapyGuide, refer to page 179.

For each pacemaker model, TherapyGuide suggests a programmable mode. It bases the suggestion on clinical conditions such as the condition of the sinus node and the quality of AV conduction.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 1

Rationale for mode selection

TherapyGuide offers a Rationale screen that shows the basis for each setting of pacing modes and of other parameters. Figure 1-2 shows a typical Rationale screen. To access the screen, perform the following steps:

Figure 1-2. Mode selection rationale used by TherapyGuide

1. Interrogate the pacemaker (before or after implant).

2. Select the Params icon. On the Therapy Parameters screen, select

the [TherapyGuide] button to open the TherapyGuide window.

3. Select the [Rationale…] button to open the Rationale window.

4. Select [Close] twice to return to the Therapy Parameters screen.

Note: It is not necessary to do any parameter programming at this time. Refer to the Adapta/Versa/Sensia/Relia Pacemaker Programming Guide for instructions on programming parameters using TherapyGuide.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Indications

Pacing modes

Indications

Note: This section contains information for all models of the Medtronic Adapta/Versa/Sensia/Relia implantable pulse generators. For information about a specific model or series, refer to the implant manual for that device.

These Medtronic Adapta/Versa/Sensia/Relia implantable pulse generators (IPGs) are indicated for use to improve cardiac output, prevent symptoms, or protect against arrhythmias related to cardiac impulse formation or conduction disorders.

These devices are indicated for use in patients who are experiencing exercise intolerance or exercise restrictions related to an arrhythmia. Using rate response modes may restore heart rate variability and improve cardiac output.

Adapta/Versa/Sensia/Relia implantable pulse generators are indicated for single use only.

This device is also indicated for VDD pacing in patients who have adequate rates and one or both of the following conditions.

■

A requirement for ventricular pacing when adequate atrial rates and adequate intracavitary atrial complexes are present. This includes the presence of complete AV block when atrial contribution is needed for hemodynamic benefit or when pacemaker syndrome had existed or is anticipated.

■

A requirement for intermittent ventricular pacing despite a normal sinus rhythm and normal AV conduction.

Contraindications

Note: This section contains information for all models of the

Medtronic Adapta/Versa/Sensia/Relia implantable pulse generators. For information about a specific model or series, refer to the implant manual for that device.

There are no known contraindications for the use of pacing as a therapy to control heart rate. The patient’s age and medical condition may influence the selection of the pacing system, the mode of operation, and the implant technique used by the physician.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 1

MVP modes

Rate responsive modes may be contraindicated for patients who cannot tolerate pacing rates above the programmed Lower Rate.

Medtronic Adapta/Versa/Sensia/Relia implantable pulse generators (IPGs) are contraindicated for the following applications:

■

Use of an implantable cardioverter defibrillator (ICD) with a unipolar-only IPG or in those cases in which unipolar leads are implanted for the other models described. Pacing in the unipolar configuration may cause the ICD to deliver inappropriate therapy or to withhold appropriate therapy.

■

Dual chamber pacing in patients with chronic or persistent supraventricular tachycardias, including atrial fibrillation or flutter.

■

VDD mode operation in patients with sinus disorders.

■

Single chamber atrial pacing in patients with AV conduction disturbance.

Two MVP modes are available: AAIR<=>DDDR and AAI<=>DDD.

Note: For information about AAIR<=>DDDR and AAI<=>DDD modes, refer to “Managed Ventricular Pacing (MVP)” on page 142.

DDDR mode

Note: For information about the AAIR<=>DDDR mode, refer to

“Managed Ventricular Pacing (MVP)” on page 142.

In the DDDR mode, the pacemaker tracks the faster of the intrinsic atrial rate or the sensor-indicated rate. If the intrinsic rate is faster, the DDDR mode provides atrial synchronous pacing; otherwise, AV sequential pacing occurs at the sensor-indicated rate.

■

Rate limits for atrial tracking (Upper Tracking Rate)1 and sensor tracking (Upper Sensor Rate) are separately programmable.

The Total Atrial Refractory Period (TARP) may limit the tracking rate to a lesser value. Refer to Chapter 3 for more information on TARP.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Pacing modes

DDDR mode

■

The AV intervals that follow sensed atrial events (SAV) and paced atrial events (PAV) are separately programmable, and they can be programmed to shorten with increasing rates (Rate Adaptive AV) or to change with intrinsic conduction times (Search AV+).

■

A nonrefractory sensed event in either chamber inhibits pacing in that chamber. A ventricular nonrefractory sensed event in the VA interval that is not preceded by an atrial sense (AS or AR) is a pacemaker-defined PVC and starts a new VA interval.

Sensor-indicated

Interval

A P

V P

Parameters:

Lower Rate = 60 min

Sensor-indicated Rate = 90 min (667 ms)

A P

-1

(1000 ms) PAV Interval = 200 ms PVARP = 280 ms

Figure 1-3. Example of DDDR mode operation

V S

-1

SAV Interval = 170 ms

Sensor-indicated

Interval

A S

V S

A P

V P

A S

V P

200 ms

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

DDD mode

Chapter 1

DDD mode

Note: For information about the AAI<=>DDD mode, refer to “Managed Ventricular Pacing (MVP)” on page 142.

The DDD mode provides atrial synchronous pacing in the presence of intrinsic atrial activity; otherwise, AV sequential pacing occurs at the Lower Rate.

■

Each atrial paced or nonrefractory atrial sensed event starts an AV interval and a lower rate interval. The AV intervals that follow sensed atrial events (SAV) and paced atrial events (PAV) are separately programmable, and the SAV may be optionally programmed to shorten with increasing rate (Rate Adaptive AV) or to change with intrinsic conduction times (Search AV+).

■

A ventricular paced event may track an atrial sensed event up to the programmed Upper Tracking Rate.

■

A ventricular nonrefractory sensed event in the VA interval that

is not preceded by an atrial sense (AS or AR) is a pacemaker-defined PVC and starts a new VA interval.

Lower Rate Interval

A P

V P

Parameters:

Lower Rate = 60 min

-1

(1000 ms) PAV Interval = 200 ms

A P

V S

SAV Interval = 170 ms

Figure 1-4. Example of DDD mode operation

The Total Atrial Refractory Period (TARP) may limit the tracking rate to a lesser value.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Lower Rate Interval

A S

V S

200 ms

A P

DDIR mode

Pacing modes

DDIR mode

The DDIR mode provides dual chamber, sensor-driven, atrioventricular (AV) sequential pacing for heart rate variation without atrial tracking.

■

Atrial pacing occurs at the sensor-indicated rate. If it is not inhibited, ventricular pacing occurs at the end of the PAV interval.

■

The AV intervals that follow paced atrial events (PAV) are separately programmable, and they can be programmed to shorten with increasing rates (Rate Adaptive AV) or to change with intrinsic conduction times (Search AV+).

■

An atrial event sensed outside the PVARP will inhibit a scheduled atrial stimulus but will not start an AV interval. That is, ventricular paced events after such sensed atrial events occur at the sensor-indicated rate. The following ventriculoatrial (VA) interval may be extended slightly to avoid an increasing atrial paced rate.

■

A ventricular nonrefractory sensed event in the VA interval starts a new VA interval.

Sensor-indicated

Interval

A P

V P

Parameters:

Lower Rate = 60 min

Sensor-indicated Rate = 90 min

-1

(1000 ms) PAV Interval = 200 ms

Figure 1-5. Example of DDIR mode operation

A P

V P

-1

(667 ms)

Sensor-indicated

Interval

A S

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Sensor-indicated VA

Interval

V P

Sensor-indicated

A P

V P

Interval

200 ms

A P

Chapter 1

DDI mode

The DDI mode provides dual chamber atrioventricular (AV) sequential pacing with atrial sensing but without atrial tracking.

■

Atrial pacing occurs at the Lower Rate. If it is not inhibited, ventricular pacing occurs at the end of the PAV interval.

■

The AV intervals that follow paced atrial events (PAV) are separately programmable, and they can be programmed to change with intrinsic conduction times (Search AV+).

■

An atrial event sensed outside the PVARP will inhibit a scheduled atrial stimulus but will not start an AV interval. Ventricular paced events after such sensed atrial events occur at the Lower Rate.

■

A ventricular nonrefractory sensed event in the ventriculoatrial (VA) interval starts a new VA interval.

Lower Rate Interval

A P

V P

Parameters:

Lower Rate = 60 min

Lower Rate Interval Lower Rate VA Interval

A P

V P

-1

(1000 ms) PAV Interval = 200 ms

A S

Figure 1-6. Example of DDI mode operation

A P

V P

200 ms

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

DVIR mode

Pacing modes

DVIR mode

The DVIR mode provides AV sequential pacing at the sensor-indicated rate unless inhibited by ventricular sensed events.

■

Atrial pacing occurs at the sensor-indicated rate. If it is not inhibited, ventricular pacing occurs at the end of the PAV interval.

■

The DVIR mode ignores intrinsic atrial events. Sensing occurs only in the ventricle. A ventricular nonrefractory sensed event during the ventriculoatrial (VA) interval starts a new VA interval.

Sensor-indicated

Interval

A P

V P

Parameters:

Lower Rate = 60 min

Sensor-indicated Rate = 90 min

-1

(1000 ms) PAV Interval = 200 ms

Figure 1-7. Example of DVIR mode operation

A P

V S

-1

(667 ms)

Sensor-indicated VA

Interval

V S

Sensor-indicated

A P

V P

Interval

A P

200 ms

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 1

DVI mode

The DVI mode provides dual chamber AV sequential pacing without atrial sensing/tracking.

■

Atrial pacing occurs at the Lower Rate. If it is not inhibited, ventricular pacing occurs at the end of the PAV interval.

■

The AV intervals that follow paced atrial events (PAV) are separately programmable, and they can be programmed to change with intrinsic conduction times (Search AV+).

■

Sensing occurs only in the ventricle, and intrinsic atrial events are ignored. A ventricular nonrefractory sensed event during the VA interval starts a new ventriculoatrial (VA) interval.

Lower Rate Interval

A P

V P

Parameters:

Lower Rate = 60 min

Lower Rate VA Interval

A P

V S

-1

(1000 ms) PAV Interval = 200 ms

V S

Figure 1-8. Example of DVI mode operation

A P

V P

200 ms

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

VDD mode

Pacing modes

VDD mode

The VDD mode provides atrial synchronous pacing (or VVI pacing at the Lower Rate). The ventricle is paced synchronously up to the programmed Upper Tracking Rate.

Sensing occurs in both the

atrium and ventricle, but pacing occurs only in the ventricle.

■

To promote atrial synchronous pacing at slow rates, a sensed atrial event occurring near the end of the Lower Rate interval will be followed by the programmed SAV interval. The result is an extension of the ventricular lower rate.

■

The AV intervals that follow sensed atrial events (SAV) are separately programmable, and they can be programmed to shorten with increasing rates (Rate Adaptive AV) or to change with intrinsic conduction times (Search AV+).

■

A ventricular nonrefractory sensed event in the V-V interval that is not preceded by an atrial sense (AS or AR) is a pacemaker-defined PVC, and it starts a new V-V interval.

Lower Rate Interval

SAV

Interval

A S

V P

Parameters:

Lower Rate = 60 min

Upper Tracking Rate = 120 min

-1

(1000 ms) SAV Interval = 200 ms

Figure 1-9. Example of VDD mode operation

The Total Atrial Refractory Period (TARP) may limit the tracking rate to a lesser value.

A S

V P

-1

(500 ms) PVARP = 250 ms

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

A S

V P

A S

200 ms

)

Chapter 1

AAIR / ADIR modes

Sensor-indicated Interval Sensor-indicated Interval

Note: For information about the AAIR<=>DDDR mode, refer to

“Managed Ventricular Pacing (MVP)” on page 142.

The AAIR mode provides atrial-based rate responsive pacing in patients with intact AV conduction. Sensing and pacing occur only in the atrium. In the absence of sensed events, the chamber is paced at the sensor-indicated rate.

The ADIR mode operates the same as the AAIR mode except that events sensed in the ventricle are recorded by the diagnostics. When used in conjunction with Marker Channel recordings and concurrent ECG, this mode may be used to observe the conducted ventricular rhythm without affecting atrial pacing.

Note: In the AAIR and ADIR modes, atrial refractory sensed events do not restart the Upper Sensor Rate interval.

A P

A R

A P

A S

A P

200 ms

Parameters:

-1

Sensor-indicated Rate = 75 min

er Sensor Rate = 100 min-1 (600 ms

(800 ms) Atrial Refractory Period = 250 ms

Figure 1-10. Example of AAIR mode operation

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

AAI / ADI modes

Note: For information about the AAI<=>DDD mode, refer to

“Managed Ventricular Pacing (MVP)” on page 142.

The AAI mode provides single chamber inhibited atrial pacing. Sensing and pacing occur only in the atrium. Pacing occurs at the programmed Pacing Rate unless inhibited by sensed events.

The ADI mode operates the same as the AAI mode except that events sensed in the ventricle are recorded by the diagnostics. When used in conjunction with Marker Channel recordings and concurrent ECG, this mode may be used to observe the conducted ventricular rhythm without affecting atrial pacing.

Pacing modes

AAI / ADI modes

Pacing Rate Interval

A P

Parameters:

Pacing Rate = 75 min

A R

Pacing Rate Interval

A P

-1

(800 ms) Atrial Refractory Period = 250 ms

A S

Figure 1-11. Example of AAI mode operation

A P

200 ms

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 1

VVIR / VDIR modes

The VVIR mode provides ventricular rate responsive pacing in patients for whom atrial-based pacing is deemed unnecessary or inappropriate. In the absence of sensed events, the ventricle is paced at the sensor-indicated rate.

The VDIR mode operates the same as the VVIR mode except that events sensed in the atrium are recorded by the diagnostics. When used in conjunction with Marker Channel recordings and concurrent ECG, this mode may be used to observe the underlying atrial rhythm without affecting ventricular pacing.

Note: In the VVIR and VDIR modes, ventricular refractory sensed events restart the Upper Sensor Rate interval.

Sensor-indicated

Interval

V P

Parameters:

Lower Rate = 60 min

Sensor-indicated Rate = 90 min

-1

(1000 ms) Upper Sensor Rate = 120 min-1 (500 ms)

Figure 1-12. Example of VVIR mode operation

Sensor-indicated

Interval

Upper Sensor

Rate Interval

V P

-1

(667 ms) Ventricular Refractory Period = 300 ms

V R

Sensor-indicated

Interval

V P

200 ms

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

VVI / VDI modes

The VVI mode provides single chamber inhibited pacing at the programmed Pacing Rate unless inhibited by sensed events. Sensing occurs only in the ventricle.

The VDI mode operates the same as the VVI mode except that events sensed in the atrium are recorded by the diagnostics. When used in conjunction with Marker Channel recordings and concurrent ECG, this mode may be used to observe the underlying atrial rhythm without affecting ventricular pacing.

Pacing modes

VVI / VDI modes

Pacing Rate Interval

V P

Parameters:

Pacing Rate = 60 min

Ventricular Refractory Period = 300 ms

-1

(1000 ms)

Figure 1-13. Example of VVI mode operation

Pacing Rate Interval

V P

V S

200 ms

V P

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 1

AAT / VVT modes

In the AAT and VVT modes, pacing occurs at the programmed Lower Rate, but a nonrefractory sensed event triggers an immediate pacing output (rather than inhibiting such output). With the exception that pacing outputs occur when events are sensed, the triggered modes operate identically to the corresponding inhibited modes.

Note: Programmed triggered pacing will not occur faster than 300 ms (200 min programmed triggered pacing is not limited to 300 ms (200 min

Pacing Rate Interval

V P

Parameters:

Pacing Rate = 60 min

Ventricular Refractory Period = 300 ms

V R

-1

(1000 ms)

Figure 1-14. Example of VVT mode operation

-1

) from the previous paced event. Temporary

Pacing Rate Interval

V P

T P

V P

200 ms

-1

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

DOOR / AOOR / VOOR modes

The DOOR, AOOR, and VOOR modes operate as follows:

■

The DOOR mode provides asynchronous AV sequential pacing at the sensor-indicated rate. Intrinsic events are ignored.

■

The AOOR and VOOR modes provide single chamber pacing at the sensor-indicated rate. Intrinsic events are ignored.

Pacing modes

DOOR / AOOR / VOOR modes

Sensor-indicated

Interval

A P

V P

Parameters:

Lower Rate = 60 min

Sensor-indicated Rate = 90 min

A P

-1

(1000 ms) PAV Interval = 200 ms

Figure 1-15. Example of DOOR mode operation

Sensor-indicated

Interval

V P

-1

(667 ms)

Sensor-indicated

Interval

A P

V P

Sensor-indicated

Interval

A P

V P

A P

200 ms

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 1

DOO / AOO / VOO modes

The DOO, AOO, and VOO modes operate as follows:

In addition to being directly programmable, the DOO mode is the Magnet mode of the corresponding dual chamber modes, except for the VDD mode, which is the VOO mode. AOO and VOO modes are the Magnet modes of the corresponding atrial and ventricular single chamber modes, respectively.

■

The DOO mode provides AV sequential pacing at the programmed Lower Rate with no inhibition by intrinsic events.

■

The AOO and VOO modes provide pacing at the programmed Lower Rate with no inhibition by intrinsic events in the applicable chamber.

Lower Rate Interval

A P

V P

Parameters:

Lower Rate = 60 min

(1000 ms)

Lower Rate Interval Lower Rate Interval

A P

V P

-1

PAV Interval = 200 ms

A P

Figure 1-16. Example of DOO mode operation

A P

V P

200 ms

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

ODO / OAO / OVO modes

Warning: Never program these modes for pacemaker-dependent

patients. For such patients, use the programmer’s inhibit function for brief interruption of outputs.

In the ODO, OAO, and OVO modes, sensing occurs in the designated chamber or chambers. When used in conjunction with Marker Channel telemetry and concurrent ECG, these modes may be used to observe underlying rhythms.

■

Blanking periods in these modes are automatically minimized to maximize the sensing window or windows. Thus, Marker Channel telemetry may display sense markers for cardiac events (for example, far-field R waves) that otherwise would not appear due to longer blanking.

■

No timing intervals or refractory periods are used.

Pacing modes

ODO / OAO / OVO modes

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Introduction to rate responsive pacing 36

Preset rate response at implant 37

Rate Profile Optimization operation 39

Individualizing Rate Profile Optimization 46

Activity sensor operation 48

Manual control of Rate Profile Optimization 53

Rate response2

Chapter 2

Introduction to rate responsive pacing

Rate response

The pacemaker may provide appropriate rate response for patients who require cardiac pacing support at both submaximal and maximal rates. Submaximal rates are moderate pacing rates near the Activities of Daily Living Rate (ADL Rate) obtained during typical daily activities, such as walking or daily chores. Maximal rates are rates (at or near the Upper Sensor Rate) obtained during vigorous activities. To achieve appropriate rate response, the pacemaker provides activity sensor-driven pacing with rate response control in both the ADL rate range and the exertion rate range.

The pacemaker provides appropriate rate response by employing the following operations:

■

Three programmable rates control the submaximal and maximal rate ranges: Lower Rate, ADL Rate (Activities of Daily Living Rate), and Upper Sensor Rate. The ADL Rate is equivalent to the average target rate that the patient achieves for moderate activities.

■

Independent control of rate response is provided in both the ADL and exertion rate ranges.

Automatic features

For models in a rate responsive mode, the pacemaker automatically enables rate response after implant and automatically adjusts rate response, if necessary, once each day.

■

During the first 30 minutes after implant, pacing occurs at the implanted mode but without rate response. 30 minutes after implant, rate response operation is enabled.

■

Once each day, rate response is assessed and adjusted, if necessary, in the ADL and exertion rate ranges. The assessment is based on comparing the pacemaker’s historical sensor-indicated rate profiles against a clinician prescribed target rate profile of the patient. If the rate profiles differ, rate response is adjusted slightly in the appropriate rate range, and the assessment is repeated again the next day.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

For further information

Refer to “Rate Profile Optimization operation” on page 39 for information on how the pacemaker optimizes rate response.

Preset rate response at implant

Overview

Pacemakers shipped in rate responsive modes operate in a non rate responsive mode until implant detection is completed, which is typically 30 minutes after implant. Thereafter, the pacemakers automatically enable rate responsive pacing. Consequently, no programming is required for rate response operation.

Three pacing rate controls

If customization of rate response is desired, three pacing rates are provided to control the ADL and exertion rate ranges:

■

Lower Rate defines the slowest rate at which pacing occurs in the absence of a sinus rate or physical activity.

■

ADL Rate (Activities of Daily Living Rate) is the approximate rate that the patient’s heart is expected to reach during moderate exercise.

■

Upper Sensor Rate provides the upper limit for the sensor-driven rate during vigorous exercise.

Rate response

Preset rate response at implant

Refer to “Rates” on page 56 for additional considerations when selecting pacemaker rates.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 2

Preset rate response at implant

Starting rate response immediately

In situations where the clinician wishes to start rate responsive pacing before the 30-minute implant detection period is completed, perform the following steps:

1. After the device is implanted, program Implant Detection to “Off/Complete.”

2. Configure pace and sense lead polarities and Lead Monitor.

3. Verify that Rate Profile Optimization is On.

4. Verify that the parameter values for Lower Rate, ADL Rate, and Upper Sensor Rate are appropriate.

5. Verify that the parameter values for ADL Response, Exertion Response, Activity Threshold, Activity Acceleration, and Activity Deceleration are appropriate.

For further information

Refer to “Rate Profile Optimization operation” on page 39 and “Individualizing Rate Profile Optimization” on page 46.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Rate Profile Optimization operation

Overview

When Rate Profile Optimization is programmed On, the pacemaker can adapt ADL and exertion rate response levels once each day by comparing the patient’s current sensor rate profiles against a target rate profile. This feature is intended to provide automatic and independent monitoring of rate response at both moderate rates for daily patient activities, such as walking and daily chores, and at exertion rates for vigorous patient activities.

Optimization can be individualized to the patient’s activity levels. Refer to “Individualizing Rate Profile Optimization” on page 46.

Optimization can also operate in the background when a non rate responsive mode is programmed. This can provide appropriate rate response to patient activity if rate response is needed later or for certain therapy features, such as mode switching to a non-atrial tracking rate responsive mode.

Rate control in the ADL and exertion rate ranges

Rate response

The pacemaker maintains linear rate control between the activity sensor signal and the sensor-indicated rate from the Lower Rate to the ADL Rate. Refer to “How Activity Threshold influences rate” on page 48. It maintains independent linear rate control in the exertion rate range. Optimization controls how rapidly and to what level the sensor-indicated rate increases and decreases in these two rate ranges. The three programmable rate controls [Lower Rate, ADL Rate (Activities of Daily Living Rate), and Upper Sensor Rate] define the rate ranges (see Figure 2-1).

■

Moderate pacing rates are achieved during typical daily patient activities. These rates (in the ADL rate range) are at or near the ADL Rate.

■

Exertion pacing rates are achieved during vigorous activities. These rates (in the exertion rate range) are at or near the Upper Sensor Rate

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 2

Rate Profile Optimization operation

Figure 2-1 shows a graph of sensor-indicated rate as a function of increasing activity. The sensor-indicated rate curve has two slopes. The first slope, which controls how aggressively the pacing rate increases from the Lower Rate to the ADL Rate, is determined by the programmed ADL Response parameter. The second slope, which controls how aggressively the pacing rate approaches the Upper Sensor Rate, is determined by the programmed Exertion Response parameter.

When you program new values for rates or Rate Profile Optimization, immediate changes occur. The new values are predictions based on automatic diagnostic data and the selected Rate Profile Optimization settings. The pacemaker continues to adjust Rate Response over time.

Note: If the patient does not have any data in the Sensor Indicated Rate Profile diagnostic, optimization does not adjust immediately when these parameters are programmed. 24 hours of diagnostic data are required.

ADL rate

Upper

Sensor

Rate

ADL Rate

Lower Rate

Figure 2-1. A sensor-indicated rate curve

range

Increasing activity →

Exertion rate

range

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Optimization using rate profiles

Optimization of rate response occurs independently in both the ADL rate range and the exertion rate range. The sensor-indicated rate curve is assessed daily based on the following rate profile data:

Sensor rate profile – An actual rate versus time distribution of the patient’s averaged sensor-indicated rates. Once each day, the pacemaker collects a daily sensor rate profile and cumulates the data into a long-term average. Both the daily and long-term rate profiles are assessed each day to determine if adjustments to rate response are required. The long-term sensor rate profile is automatically stored in the Sensor Indicated Rate Profile diagnostic.

Target rate profile – A programmable rate versus time distribution of the patient’s desired rates. The ADL Response and Exertion Response parameters define the percentage of time that the sensor-indicated rate stays in the ADL rate range and in the exertion rate range, respectively.

Figure 2-2 shows a typical rate profile (either a sensor rate profile or a target rate profile).

Rate response

Rate Profile Optimization operation

30%

20%

10%

Percentage of time

Lower Rate ADL Rate Upper Sensor

Figure 2-2. Example of a rate profile

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

ADL rate

range

Exertion rate

range

Rate

Chapter 2

Rate Profile Optimization operation

Daily optimization of rate response

Once each day, the pacemaker evaluates the percentage of time the sensor rate is in the ADL and exertion rate ranges by comparing the daily and long-term sensor rate profiles against the target rate profile. This operation follows the sequence shown in Figure 2-3.

■

The pacemaker calculates the sensor indicated rate based on the activity sensor signal.

■

From the actual sensor indicated rate values, it generates a daily sensor rate profile. It also merges that data into a long-term sensor rate profile.

■

It compares the target rate profile to the daily and long-term sensor rate profiles. Refer to Figure 2-4 and Figure 2-5 for details.

■

If the sensor rate profiles match the target rate profile or if the daily and long-term sensor rate profiles contradict each other, no rate response adjustments occur.

■

Otherwise it makes an automatic adjustment to rate response, which affects the calculation of the sensor-indicated rate in either or both of the rate ranges.

■

This sequence repeats each day.

As a result of this operation, the pacemaker automatically adjusts rate response in the ADL and exertion ranges, if necessary, based on the following criteria:

■

If the sensor rate profiles show a higher percentage of time spent pacing than the target rate profile, rate response for the pertinent rate range is set to be less responsive. Conversely, if a lower percentage of time spent pacing is profiled than targeted for, rate response is set to be more responsive.

■

If the sensor rate profiles match the target rate profile or the daily and long-term sensor rate profiles contradict each other, no rate response adjustments occur.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Rate response

Rate Profile Optimization operation

Sensor signal

processing

Rate calculation

Daily sensor

Adjust ADL rate

response as needed

based on

comparison

rate profile

30%

20%

10%

Compare

Adjust exertion rate

response as needed

based on

comparison

Figure 2-3. Daily operation of Rate Profile Optimization

Long-term sensor

rate profile

30%

20%

10%

Compare

30%

20%

10%

Target rate profile

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 2

Rate Profile Optimization operation

The goal of this operation is to keep the patient’s sensor rate profiles equivalent to the target rate profile. This is shown in two examples.

In Figure 2-4, a comparison of the sensor rate profile and target rate profile shows that pacing in the ADL rate range occurs for a larger percentage of time than was targeted. In the sensor rate curve, rate response is adjusted to be less aggressive in this range.

The same comparison shows that pacing in the exertion rate range occurs for a smaller percentage of time than was targeted. In the sensor rate curve, rate response is adjusted to be more aggressive in this range.

Rate response is made more aggressive

ADL rate

range

Percentage of time

Increasing rate

Target rate profile

Sensor rate profile

Figure 2-4. Result of comparing rate profiles: first example

Exertion

rate

range

Increasing rate

Rate response is made less aggressive

Increasing activity

Old rate response curve

New rate response curve

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Rate response

Rate Profile Optimization operation

The example in Figure 2-5 is the opposite of the one in Figure 2-4. Lower than targeted pacing in the ADL rate range results in a rate response adjustment to make rate response more aggressive in this range. Higher than targeted pacing in the exertion rate range results in rate response that is less aggressive in this range.

Rate response is made less aggressive

ADL rate

range

Percentage of time

Increasing rate

Target rate profile

Sensor rate profile

Figure 2-5. Result of comparing rate profiles: second example

Exertion

rate

range

Increasing rate

Rate response is made more aggressive

Note: Two additional cases are possible:

■

Lower than targeted pacing in both the ADL and exertion rate range. Rate response is adjusted to be more aggressive in both ranges.

■

Higher than targeted pacing in both the ADL and exertion rate range. Rate response is adjusted to be less aggressive in both ranges.

Adaptations in Optimization operation

The pacemaker adapts rate response more rapidly for the first ten days after Optimization is first activated post-implant or after certain rate response parameters are manually reprogrammed (e.g., Lower Rate, ADL Rate, Upper Sensor Rate, ADL Response, or Exertion Response). The intent is to quickly match rate response to the target rate profile prescribed by the parameter changes.

Increasing activity

Old rate response curve

New rate response curve

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 2

Individualizing Rate Profile Optimization

Note: If the patient does not have any data in the Sensor Indicated Rate Profile diagnostic, optimization does not adjust immediately when these parameters are programmed.

Optimization is skipped on any day that a device interrogation or parameter programming occurs.

Individualizing Rate Profile Optimization

Overview

The clinician can prescribe a target rate profile using the ADL Response and Exertion Response parameters to match the patient’s life-style or activity levels. The programmable ADL Response parameter alters the targeted rate distribution in the ADL rate range, while the Exertion Response parameter alters the rate distribution in the exertion rate range.

ADL rate profiles

The nominal setting for the ADL Response parameter is “3.” Programming a higher number redefines the target rate profile to spend more time pacing at or above the ADL Rate, thereby increasing rate responsiveness in the ADL rate range. Programming a lower number redefines the rate profile to spend less time pacing at or above the ADL Rate, thereby decreasing rate responsiveness.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Exertion rate profiles

The nominal setting for the Exertion Response parameter is “3.” Programming a higher number redefines the target rate profile to spend more time pacing near the Upper Sensor Rate, thereby increasing rate responsiveness in the exertion rate range. Programming a lower number redefines the rate profile to spend less time pacing near the Upper Sensor Rate, thereby decreasing rate responsiveness.

Programming guidelines

If it is necessary to adjust rate response from the nominal setting, first verify that the three rate controls are appropriate for the patient. Refer to “Three pacing rate controls” on page 37.

If these rate control settings are appropriate, the ADL Response and/or Exertion Response settings can then be adjusted based on the guidelines in Table 2-1.

Tabl e 2- 1. ADL Response and Exertion Response guidelines

Rate region Patient Select these settings

Rate response

Individualizing Rate Profile Optimization

ADL Response

Lower Rate to ADL Rate

ADL Rate to Upper Sensor Rate

If a higher Exertion Response setting has not produced the desired rate response, increase the ADL Response setting.

Reached ADL Rate too quickly

Reached ADL Rate too slowly

Reached Upper Sensor Rate too quickly

Reached Upper Sensor Rate too slowly

Lower number (less rate response)

Higher number (more rate response)

Exertion Response

Lower number (less rate response)

Higher number (more rate response)

For more detailed programming guidelines, refer to Table E-14 and Table E-15, which list the targeted time spent pacing for the five ADL Response and Exertion Response settings.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 2

Activity sensor operation

Overview

Activity sensor based pacing is controlled by the following programmable parameters:

■

Activity Threshold determines the minimum intensity of detected physical activity to which the pacemaker responds.

■

Activity Acceleration and Activity Deceleration times control how rapidly the pacing rate changes in response to increased or decreased activity. One programmable Activity Deceleration setting, “Exercise,” provides an extended deceleration period following prolonged exercise.

Note that Activity Threshold, Activity Acceleration, and Activity Deceleration are automatically set to shipping settings 30 minutes after implant or can be manually programmed.

How Activity Threshold influences rate

A transducer, bonded to the pacemaker circuitry, is deflected by physical motion. The activity sensor converts detected motion into electrical signals. The programmed Activity Threshold screens out activity signals below the selected setting. Detected sensor signals vary from patient to patient. Only sensor signals whose amplitude exceeds the programmed Activity Threshold (as shown in Figure 2-6) are used in computing the sensor-indicated rate. The lower the Activity Threshold, the smaller the signal required to influence the sensor-indicated rate.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Activity

Sensor Output

Rate response

Activity sensor operation

Settings

High

Med/High

Med/Low

Low

Med/Low

Med/High

High

Time

Activity Threshold = Medium/Low

Figure 2-6. Activity sensor signal (threshold set to medium/low)

Evaluating the Activity Threshold setting

Activities such as walking increase the pacing rate; sitting results in pacing at or near the programmed Lower Rate. Use Table 2-2 as a guide for selecting an appropriate setting.

Tabl e 2- 2. Activity Threshold guidelines

Programmable settings

Low Responds to most body activity, including minimal

Medium/Low Limited response to minimal exertion; responds to

Medium/High Limited response to moderate body movements

High Responds to only vigorous body movements and

Typical rate performance

exertion.

moderate or greater exertion.

and exertion.

exertion.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 2

Activity sensor operation

How Activity Acceleration and Deceleration influence rate

Activity Acceleration and Activity Deceleration times control how rapidly the pacing rate changes in response to increased or decreased physical activity. One programmable Activity Deceleration setting, “Exercise,” provides an extended deceleration period following prolonged exercise.

■

Activity Acceleration time is the time required to achieve approximately 90% of the difference between the current rate and a higher steady-state rate consistent with the current level of activity. Figure 2-7 shows a graphic representation of the acceleration curves at the onset of strenuous exercise.

■

Activity Deceleration time is the time required to achieve approximately 90% of the difference between the current rate and a lower steady-state rate consistent with the current level of activity. Figure 2-8 shows a graphic representation of the deceleration curves at an abrupt cessation of strenuous exercise.

Upper

Sensor

Rate

Rate Range

Lower

Rate

Figure 2-7. Activity Acceleration curves

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Programmable Settings

210453

Time (Minutes)

Activity Acceleration

15 Seconds 30 Seconds 60 Seconds

Upper

Sensor

Rate

Rate Range

Lower

Rate

Time (Minutes)

Figure 2-8. Activity Deceleration curves

Rate response

Activity sensor operation

Activity Deceleration

Programmable Settings

2.5 Minutes

5 Minutes

10 Minutes

6543210 78910

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 2

Activity sensor operation

Exercise Deceleration operation

Activity Deceleration programmed to “Exercise” extends the rate slowing period following an exercise episode, providing up to 20 minutes of rate deceleration. When it is programmed on, the pacemaker uses activity sensor data to detect periods of vigorous, prolonged exercise. At the end of such an exercise period, the pacemaker uses a longer deceleration curve for the central portion of the programmed rate range. The actual deceleration rate is determined dynamically based on the intensity and duration of exercise and the new level of activity. Figure 2-9 shows the composite deceleration curve that applies after the abrupt cessation of sustained exercise.

Upper

Sensor

Rate

5 Minute Deceleration Curve

Begins Exercise Deceleration

Ends Exercise Deceleration

Rate Range

Lower

Rate

Time (Minutes)

Figure 2-9. Exercise Deceleration

5 Minute Deceleration Curve

121086420 1416182022

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Manual control of Rate Profile Optimization

Overview

As an alternative to automatic Rate Profile Optimization, a programmer assisted Exercise test can be used to manually set rate response for the ADL and exertion rate ranges. The Exercise test is used to immediately set rate response to certain levels. Rate response parameters remain set to their programmed values if Optimization is Off. When Optimization is On, it can adjust these parameters once each day.

Evaluate and program rate response

The Exercise test is used to evaluate the patient’s rate response and allow the programmer to customize two rate response control parameters:

■

ADL Setpoint (Activities of Daily Living Setpoint) determines the minimum sensor response to pace at the ADL Rate, which falls within the ADL rate range.

■

UR Setpoint (Upper Rate Setpoint) determines the minimum sensor response to pace at the Upper Sensor Rate, which is at the upper limit of the exertion rate range.

Rate response

Note: The programmed ADL Setpoint setting must be less than the UR Setpoint setting.

Refer to the Adapta/Versa/Sensia/Relia Pacemaker Programming

Guide for programming instructions.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Rates 56

AV intervals 63

Rate Adaptive AV 66

Search AV+ and diagnostic 69

Blanking periods 73

Refractory periods 75

High rate atrial tracking 84

Pacemaker timing3

Chapter 3

Rates

Overview

The following programmable rates control timing in the pacemaker:

■

Normal operating rates:

– Lower Rate

– ADL Rate

– Upper Tracking Rate

– Upper Sensor Rate

■

Other operating rates:

– Sleep Rate (for Sleep function)

– Hysteresis Rate (for single chamber demand and

triggered modes)

– Sinus Preference Zone (for Sinus Preference)

– Intervention Rate (for Rate Drop Response)

– Overdrive Rate (for Post Mode Switch Overdrive Pacing)

– Maximum Rate (for Conducted AF Response)

– Maximum Rate (for Atrial Preference Pacing)

Additionally, rates calculated by the pacemaker are used for some operations. These are:

■

Sensor-indicated rate

■

Mean atrial rate

The other operating rates are described in “Special therapy options” on page 133 along with the functions that use them. The normal rates are described in this chapter.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

A-A and V-V timing

Pacemaker timing

Rates

A-A timing – In all modes that pace the atrium, the pacemaker times from atrial event to atrial event (A-A timing). This timing method mimics a natural sinus rhythm, producing A-A intervals that are nearly equal, except when timing is interrupted by one of the following:

■

PACs in DDIR and DDI modes

■

PVCs in DDDR, DDD, DDIR, DDI modes (PVC Response operation)

■

A ventricular sensed event during the VA interval in the DVIR and DVI modes

■

An atrial refractory sensed event that triggers an NCAP extension

VA intervals vary due to adjustments by A-A timing operations in order to achieve sensor-indicated or lower rate operation in the presence of varying AV conduction.

V-V timing – In modes that do not pace the atrium (e.g., VDD or VDIR) or single chamber ventricular modes, the pacemaker times from ventricular event to ventricular event (V-V timing).

Lower Rate

The programmed Lower Rate defines the slowest rate at which pacing occurs during a mode’s basic operation. In rate responsive modes, in the absence of sensor-detected activity, the sensor-indicated rate is equal to the programmed Lower Rate.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 3

Rates

Lower Rate Interval

DDD

Parameters: Lower Rate = 60 min-1 (1000 ms) PVARP = 300 ms

PAV Interval = 200 ms Ventricular Refractory Period = 240 ms

SAV Interval = 180 ms

Figure 3-1. Example of Lower Rate operation

Operating lower rate

Under certain circumstances, the programmed Lower Rate may be overridden by an operating lower rate that is higher or lower than the programmed value. The following rates may become the operating lower rate:

■

Switching from and back to atrial tracking mode (for Mode Switch)

■

Conducted AF Response determined rate

■

Sinus Preference Zone (for Sinus Preference)

■

Sleep Rate (for Sleep function)

■

Intervention Rate (for Rate Drop Response)

■

Hysteresis Rate (for single chamber modes)

■

Threshold Margin Test rate of 100 min

■

Magnet Mode rate of 85 min

■

Recommended Replacement Time (RRT/ERI) rate of 65 min

■

Overdrive Rate (for Post Mode Switch Overdrive Pacing function)

■

Rate determined by Atrial Preference Pacing

■

Rate determined by Capture Management (ACM and VCM)

■

Sensor indicated rate

Lower Rate Interval

-1

200 ms

-1

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Selecting a Lower Rate

Program the Lower Rate to maintain adequate heart rates during periods of inactivity or during pauses in atrial rhythms when the pacemaker is operating in the DDDR, DDD, VDD, AAIR, ADIR, AAI, and ADI modes.

Note: In the VDD mode, atrial tracking near the Lower Rate may result in V-V intervals that exceed the Lower Rate interval. This is normal operation.

Lower Rates from 120 to 130 min patients. Lower Rates below 50 min primarily intended for diagnostic purposes.

Sensor-indicated rate

The sensor-indicated rate is the basic pacing rate when the pacemaker is operating in a rate responsive mode (DDDR, DDIR, DVIR, DOOR, VVIR, VDIR, VOOR, AAIR, ADIR, or AOOR). It is determined by the pacemaker based on the sensor-detected level of patient activity and the programmed rate response parameters. The sensor-indicated rate will never be greater than the Upper Sensor Rate or less than the Lower Rate.

Pacemaker timing

-1

are intended for pediatric

-1

and above 100 min-1 are

Rates

Sensor-Indicated Interval

Sensor Sensor Sensor

DDDR

Parameters: Sensor-Indicated Rate = 90 min

PAV Interval = 200 ms Ventricular Refractory Period = 220 ms

SAV Interval = 190 ms

-1

(667 ms) PVARP = 300 ms

Figure 3-2. Example of sensor-indicated rate operation

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Sensor-Indicated Interval

200 ms

Chapter 3

Rates

In rate responsive modes, the sensor-indicated rate tracks the activity sensor, which is detected by the transducer sensor’s frequency and amplitude.

■

In dual chamber rate responsive modes, the sensor-indicated interval is the AS-AP or AP-AP interval.

■

In single chamber rate responsive modes, the sensor-indicated interval is the A-A or V-V interval. In these modes, sensor-indicated rate intervals start with a sensed or paced event in the chamber being paced.

Sensor indicated rate effect on other intervals

The sensor-indicated rate is used to determine the values of certain other timing intervals. These intervals are:

■

Rate adaptive paced AV (PAV) interval

■

Sensor-varied PVARP (even in non-rate responsive DDD and VDD modes)

■

PVARP extension (sensor-corroboration before PMT intervention)

ADL Rate

The ADL Rate (Activities of Daily Living Rate) is the target rate which the patient’s heart rate is expected to reach during moderate exercise.

Upper Tracking Rate

The programmable Upper Tracking Rate is the maximum rate at which the ventricle may be paced in response to sensed atrial events when the pacemaker is operating in the DDDR, DDD, and VDD modes. Sensed atrial events below the Upper Tracking Rate will be tracked at a 1:1 ratio, but sensed events above the Upper Tracking Rate will result in pacemaker Wenckebach (for example, 6:5, 4:3, 3:2, or 2:1 block). The Upper Tracking Rate usually should be programmed to a value less than the 2:1 block rate. Refer to “High rate atrial tracking” on page 84 for details.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Upper Tracking Rate

Pacemaker timing

Rates

Parameters:

Sensor-indicated Rate = 75 min Upper Tracking Rate = 100 min SAV Interval = 200 ms

DDD

200 ms

Figure 3-3. Example of Upper Tracking Rate (Wenckebach) operation

Upper Sensor Rate

In rate responsive modes, the programmable Upper Sensor Rate provides the upper limit for the sensor-indicated rate during physical activity, particularly during vigorous exercise. In the DDDR mode, the Upper Sensor Rate may be higher than, lower than, or the same as the Upper Tracking Rate.

Programming considerations and restrictions

ADL Rate – It is recommended that the ADL Rate be at least

10 min the Lower Rate. However, programming the ADL Rate above or below these limits is permitted.

-1

less than the Upper Sensor Rate or 20 min-1 greater than

-1

(800 ms)

-1

(600 ms)

Upper rates – Programming a combination of high Upper Sensor Rate and Upper Tracking Rate and a long refractory period may result in a shorter “sensing window.” Loss of sensing in such cases could result in competitive pacing (unless Non-Competitive Atrial Pacing is programmed On). See “Non-competitive atrial pacing” on page 148 for more information.

■

Programming the Upper Tracking Rate to a value greater than the Upper Sensor Rate permits the atrial rhythm to be tracked to a rate higher than the sensor-driven rate.

■

The Upper Sensor Rate and/or Upper Tracking Rate must be greater than the Lower Rate. The Upper Sensor Rate must be greater than the ADL Rate.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 3

Rates

Rate limit

An internal circuit, independent of the pacing timers, limits single chamber atrial or ventricular pacing rates to 200 min for most single component failures. For dual chamber modes, atrial and ventricular rates are limited independently to 200 min (± 20 min

-1

). The rate limit is automatically disabled during temporary pacing in the AAI, ADI, AAT, AOO, VVI, VDI, VVT, and VOO modes to allow high rate pacing for diagnostic or therapeutic purposes.

Note: When the Upper Tracking Rate is programmed to 190, 200, or 210, the circuit limit is 227 min

Possible atrial competition at high rates

At high sensor-driven rates when the pacemaker is operating in the DDDR and DDIR modes, sensor-driven pacing may approximate the intrinsic atrial rate, with some intrinsic atrial events falling into the PVARP. This could result in asynchronous pacing with the potential for competitive atrial pacing. Consider the potential for asynchronous pacing at high rates before selecting an Upper Sensor Rate, especially for patients known to be susceptible to induction of atrial tachyarrhythmias. Weigh the benefits of high rate sensor-driven pacing against the potential for competitive pacing.

Note: Use of the Rate Adaptive AV feature and sensor-varied or automatic PVARP can reduce the likelihood of the type of asynchronous pacing described above. When the pacemaker is operating in the DDDR mode, Sinus Preference and NCAP can also be considered.

-1

(± 17 min-1).

-1

(± 20 min-1)

-1

Mean atrial rate

The mean atrial rate (MAR) is a running average of the atrial rate for use by the Rate Adaptive AV and automatic PVARP features. The average uses all A-A intervals (except AS-AP or AR-AP intervals). In order to respond quickly to rapidly increasing atrial rates, the average gives preference to shorter A-A intervals over longer intervals when calculating the MAR. Figure 3-4 shows how the MAR tracks an increasing intrinsic atrial rate.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

AV intervals

Atrial Rate Increasing by 2 min-1/beat

200

180

160

)

-1

140

120

Rate (min

100

0 5 10 15 20 25 30 35

Time (Seconds)

Figure 3-4. Increasing mean atrial rate

Pacemaker timing

AV intervals

MAR

Intrinsic Rate

Overview

In dual chamber modes, the AV intervals determine the time between the occurrence of an atrial event and the scheduled delivery of a ventricular stimulus. Separate AV intervals for paced and sensed atrial events are available. The lengths of these intervals may be programmed to fixed values or (optionally) rate adaptive or therapeutically determined.

Paced AV Interval (PAV) – PAV follows an atrial pace when the pacemaker is operating in the DDDR, DDD, DDIR, DDI, DVIR, DVI, DOOR, and DOO modes. The PAV interval duration may differ from the programmed value due to one of the following operations:

■

Rate Adaptive AV

■

Search AV+

■

Ventricular Safety Pacing

■

Non-Competitive Atrial Pacing

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

PAV

Chapter 3

AV intervals

PAV

Interval

PAV PAV

DDD

Figure 3-5. Example of PAV interval operation

Sensed AV Interval (SAV) – SAV follows an atrial sensed event

when the pacemaker is operating in an atrial synchronous pacing mode (DDDR, DDD, and VDD). The SAV interval duration may differ from the programmed value due to one of the following operations:

■

Rate Adaptive AV

■

Automatic PVARP

■

Search AV+

■

Wenckebach

For Wenckebach operation, the SAV is extended to avoid violation of the Upper Tracking Rate or the total atrial refractory period while tracking a fast intrinsic atrial rate.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Pacemaker timing

AV intervals

Figure 3-6. Example of SAV Interval operation

Selecting PAV and SAV

Using MVP or Search AV+ should eliminate the need to manually adjust the AV intervals for most patients. It is recommended that MVP or Search AV+ be used to reduce pacing in the right ventricle.

DDD

Interval

SAV

SAV SAV

SAV

Interval

However, when programming AV intervals in patients with third degree block, the general hemodynamic goal is to assure that, to the extent possible, left-atrial systole is completed before left-ventricular systole begins. To achieve this, the AV interval durations may be adjusted independently of each other.

■

To accommodate the difference in interatrial conduction times, the SAV usually should be programmed to a shorter duration than the PAV, typically 30 to 50 ms shorter. If an SAV greater than the PAV is selected, the programmer notes that this is not usual, but the selected values may be programmed if clinically warranted.

■

When the SAV is longer than the PAV, a V pace following an atrial sense will always occur after the full SAV, even when the sensor-indicated rate or Lower Rate interval expires first.

■

In certain patients, short AV intervals may be used as a prophylaxis for AV nodal or accessory pathway reentrant tachycardias in dual chamber modes.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 3

Rate Adaptive AV

Overview

■

Long PAV intervals (greater than or equal to 250 ms) should be used with caution. If intrinsic ventricular events occur and are not sensed, a long PAV may result in pacing into the ventricle’s relative refractory period, including the T wave, or loss of AV synchrony, which may precipitate retrograde activation of the atria with corresponding hemodynamic consequences and symptoms. Long PAV intervals may also result from some Search AV+ settings (see “Search AV+ and diagnostic” on page 69 and “Ventricular blanking” on page 74.

In the normal heart, AV conduction times tend to shorten as the heart rate increases and to lengthen as the heart rate decreases. The Rate Adaptive AV (RAAV) feature, available when the pacemaker is operating in the DDDR, DDD, DDIR, DVIR, DOOR, and VDD modes, mimics this physiologic response. When RAAV is programmed On, the pacemaker shortens AV intervals for atrial rates within a programmed rate range. This feature provides increased opportunity for atrial sensing, as follows:

■

Shortened SAV intervals increase the tracking range at fast atrial rates by shortening the total atrial refractory period (TARP) and increasing the 2:1 block rate. Refer to “Total Atrial Refractory Period (TARP)” on page 79 and “High rate atrial tracking” on page 84 for more information.

■

Shortened PAV intervals lengthen the atrial sensing window of the VA interval at higher sensor-driven rates.

Note: RAAV will not shorten PAV intervals to less than 30 ms or shorten SAV intervals to less than 10 ms.

Programming for Rate Adaptive AV

For RAAV operation, the SAV and PAV are programmed (as applicable) to the values desired for low rates. Three additional programmable parameters control how AV intervals are adjusted at higher rates:

Start Rate – RAAV operation of shortening SAV and PAV intervals begins at this rate.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Pacemaker timing

Rate Adaptive AV

Stop Rate – The shortest SAV and PAV occur at this rate and at all higher rates, up to the upper rate limits.

Maximum Offset – The maximum amount of time (in ms) by which the SAV and PAV intervals can be shortened.

The PAV minus the Maximum Offset gives the shortest PAV interval at the Stop Rate (e.g., 200 ms - 100 ms = 100 ms). Subtracting the Maximum Offset from the SAV gives the shortest SAV interval (e.g., 170 ms - 100 ms = 70 ms).

Figure 3-7 shows how the SAV and PAV intervals are linearly shortened as the rate increases from below the Start Rate to above the Stop Rate.

240

220

Programmed PAV

200

180

Programmed SAV

160

140

120

100

AV Interval (ms)

Shortest PAV (PAV - Max. Offset)

Shortest SAV (SAV - Max. Offset)

100

Rate (min-1)

Parameters: Programmed SAV = 170 ms Start Rate = 80 min

Programmed PAV = 200 ms Stop Rate = 150 min

Figure 3-7. Rate Adaptive AV operation (DDDR Mode)

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

150 180

Stop RateStart Rate

-1

Maximum Offset = −30 ms

-1

Chapter 3

Rate Adaptive AV

RAAV operations

Shortening of the AV interval(s) occurs when the appropriate rate exceeds the programmed Start Rate, as follows:

SAV – The mean atrial rate determines SAV adjustments. Because of how the mean atrial rate is calculated:

■

SAV adjustments will lag during rapid increases or decreases in intrinsic atrial rates.

■

The SAV is not adjusted for isolated events (PACs).

■

AS-AP or AR-AP intervals may affect the SAV value since these intervals are not used in the mean atrial rate calculation.

PAV – The sensor-indicated rate determines PAV adjustments.

The approximate difference between programmed SAV and PAV is maintained as the SAV and PAV intervals are adjusted.

Programming considerations and restrictions

Search AV+ – RAAV can be enabled while Search AV+ is

enabled. Search AV+ will operate using the AV intervals determined by the RAAV rather than the programmed AV intervals.

RAAV and sick sinus syndrome

If RAAV is activated for a sick sinus syndrome patient who has AV conduction, consider the following:

■

The rate at which AV conduction is lost should not be too low (i.e., below 90 min

■

Review of the AV Conduction Histogram diagnostic data may aid in appropriate programming of Start Rate and Stop Rate to maintain AV conduction as long as possible.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

-1

Search AV+ and diagnostic

Overview

The Search AV+ feature is intended to promote intrinsic ventricular activation in patients with intact or intermittent AV conduction and prevent inappropriate therapy in patients without conduction. Search AV+ is available when the pacemaker is programmed to the DDDR, DDD, DDIR, DDI, DVIR, DVI, or VDD mode. The pacemaker searches for the patient’s intrinsic AV conduction time and adjusts the SAV and PAV intervals either longer or shorter to promote intrinsic activation of the ventricles. When Rate Adaptive AV is active, the pacemaker also adjusts the SAV and PAV intervals relative to the rate adaptive values. If the pacemaker does not observe intrinsic ventricular activation during its periodic searches over the course of a week, it turns off the Search AV+ feature.

Programming to Search AV+

Programming Search AV+ to “On” requires setting the Max Increase to AV parameter. This parameter defines the maximum amount of time (in ms) by which the operating SAV and PAV intervals can be lengthened to allow ventricular sensing to occur. The operating SAV and PAV intervals will adapt to the observed conduction time, but will not exceed the Max Increase to AV parameter.

Pacemaker timing

Search AV+ and diagnostic

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 3

Search AV+ and diagnostic

Search AV+ operation

The pacemaker attempts to keep intrinsic conducted events in an “AV delay window” that precedes scheduled paced events. The AV delay window is set to promote intrinsic conduction to the ventricles, but end early enough to avoid fusion or pseudo-fusion beats if pacing is necessary (see Figure 3-8).

Previous 16 AV events, 8 or more VS events are within 15 ms of the scheduled VP, thus PAV and SAV are extended by 62 ms to promote intrinsic conduction.

PAV is now 212 ms

PAV is now 204 ms

Previous 16 AV events, 8 or more VS events occur 55 ms before the scheduled VP, thus PAV and SAV are shortened by 8 ms to limit long AV delays if ventricular pacing is needed.

Param eters: DDDR SAV = 120 ms

Lower Rate = 60 min

Sensor-Indicated Rate = 90 min

-1

PAV = 150 ms

Max. Increase to AV= 170 ms

Figure 3-8. Search AV+ operation

To determine when intrinsic conducted events occur, the pacemaker assesses the 16 most recent AV conduction sequences that start with a nonrefractory atrial sense (when the pacemaker is operating in the DDDR, DDD, and VDD modes) or an atrial pace (when the pacemaker is operating in the DDDR, DDD, DDIR, DDI, DVIR, and DVI modes) and end with a ventricular pace or a nonrefractory ventricular sense.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

200 ms

Pacemaker timing

Search AV+ and diagnostic

Search criteria of AV conduction times – The measured AV conduction times are classified as on time, too short or too long.

■

Too long means 8 or more of the last 16 ventricular sensed events occurred within 15 ms of the scheduled ventricular pace, or 8 or more of the last 16 ventricular events were paced events.

■

Too short means 8 or more of the last 16 ventricular sensed events occurred more than 55 ms before the scheduled ventricular pace.

Adjustment of SAV and PAV intervals – If AV conduction times are classified as too long, the pacemaker lengthens the operating SAV and PAV intervals by 62 ms for the next 16 pacing cycles to promote intrinsic conduction. The maximum that the SAV and PAV can be lengthened is limited by the Search AV+ Maximum Increase to AV parameter.

If the previous 16 AV intervals are classified as too short, the pacemaker shortens the operating SAV and PAV intervals by 8 ms for the next 16 pacing cycles. The maximum that SAV and PAV can be shortened is limited by the programmed SAV and PAV values or the RAAV Maximum Offset parameter, if RAAV is On.

Suspension of Search AV+ operation

Search AV+ promotes conduction in patients with intrinsic conduction and prevents inappropriate therapy for patients without intrinsic conduction. If AV conduction is not found, Search AV+ suspends operation for progressively longer periods: 15 minutes, 30 minutes, 1, 2, 4, 8, and 16 hours. If AV conduction is not found following 10 consecutive 16-hour suspensions (approximate duration, 1 week), the device automatically turns Search AV+ to Off.

Programming considerations and restrictions

Both Automatic PVARP and Rate Adaptive AV can shorten the AV intervals at higher rates and potentially lead to ventricular pacing.

Automatic PVARP – When automatic PVARP is active and Search AV+ is set to On, the pacemaker will ignore conduction times that are the result of automatic PVARP shortening of the SAV interval.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 3

Search AV+ and diagnostic

Rate Adaptive AV – RAAV can be enabled while Search AV+ is enabled. Search AV+ will operate using the RAAV-determined AV intervals rather than the programmed AV intervals.

MVP modes – Search AV+ is not pertinent and cannot be enabled if the pacemaker is programmed to an MVP mode (AAIR<=>DDDR or AAI<=>DDD).

Recording AV interval adaptations

AV interval diagnostics record data about AV operations for the Search AV+ feature.

Automatic Search AV+ Histogram

Programming Search AV+ parameters automatically initiates recording of data by the Search AV+ Histogram diagnostic. This histogram shows the percentage of A-VS, VS from Search, and A-VP intervals versus rate. A histogram can be displayed or printed from the Data icon.

Clearing AV interval data

AV interval data is normally cleared by the pacemaker one hour after a programming session.

However, you can select the option to clear data immediately. Be sure to save the session data or print the episode report before ending the patient session.

Search AV+ and compromised ventricular function

Consider turning Search AV+ off if intrinsic ventricular activation is not desired.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Blanking periods

Blanking periods disable sensing for a programmable or nonprogrammable interval. Signals that are blanked may originate in either chamber or from outside sources such as noise from muscle movement.

Note: Black bars indicate blanking periods.

1 Nonprogrammable Atrial Blanking

DDD

Figure 3-9. Example of dual chamber blanking operation

2 Programmable Post-Ventricular Atrial Blanking

3 Programmable Ventricular Blanking

4 Nonprogrammable Ventricular Blanking

Pacemaker timing

Blanking periods

Nonprogrammable blanking periods

Immediately following a sensed or paced event in either chamber, sensing for that chamber is blanked for a nonprogrammable period that may typically vary from 50 to 100 ms. The actual duration of the blanking period is determined dynamically by the pacemaker, based on the strength and duration of the signal. Dynamic blanking prevents sensing the same signal twice, while minimizing total blanking time.

Post-Ventricular Atrial Blanking

The programmable Post-Ventricular Atrial Blanking (PVAB) period, used when the pacemaker is operating in the DDDR, DDD, DDIR, DDI, VDD, VDIR, and VDI modes, prevents sensing of ventricular paced events or far-field R waves on the atrial lead. Any ventricular event (paced or sensed) starts the PVAB, which is also the first portion of the Post-Ventricular Atrial Refractory period (PVARP). The PVAB is limited to values equal to or less than the programmed PVARP, except in VDIR and VDI modes where PVARP does not apply.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 3

Blanking periods

Ventricular blanking

Note: PVAB is programmed to a value less than or equal to

PVARP.

The programmable Ventricular Blanking period, which follows an atrial pacing stimulus when the pacemaker is operating in the DDDR, DDD, DDIR, DDI, DVIR, and DVI modes, prevents ventricular inhibition or ventricular safety pacing due to sensing of the atrial stimulus on the ventricular lead (crosstalk). The Ventricular Blanking period also applies to the ADIR and ADI modes to prevent sensing of the atrial stimulation.

■

Long blanking periods (36 ms or greater) increase the possibility of unsensed ventricular events.

■

Long blanking periods used in conjunction with long PAV intervals (250 ms or greater) may result in pacing into the T wave when intrinsic ventricular events are blanked and not sensed. PAV values (200 ms or less) should reduce the possibility of T wave pacing.

■

Long PAV intervals may also result from some Search AV+ operation (See “Search AV+ and diagnostic” on page 69). To minimize the possibility of undersensing intrinsic events, Search AV+ reduces ventricular blanking to 20 ms unless Ventricular Safety Pacing is observed.

Single chamber atrial blanking

The programmable single chamber atrial blanking period, used when the pacemaker is operating in the AAIR, ADIR, AAI, ADI, and AAT mode, prevents sensing of far-field R waves. It is started by a paced, sensed, or refractory sensed atrial event.

Note: Atrial Blanking must be programmed at least 50 ms less than the Atrial Refractory Period.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Refractory periods

Overview

A refractory period is an interval during which an intrinsic event sensed on a particular lead channel cannot start certain timing intervals. Each refractory period begins with a blanking period, during which no sensing occurs. During the unblanked portion of a refractory period, sensing occurs, but sensed events may not directly affect timing operations. Refractory periods are intended to prevent certain timing intervals from being started by inappropriate signals such as retrograde P waves, far-field R waves, or electrical noise.

Though they may not start timing intervals, refractory sensed events are monitored by the pacemaker, and they affect the operation of PVC Response, Mode Switch, Rate Adaptive AV operation, automatic PVARP, Non-Competitive Atrial Pacing, and other features for which the periodicity or number of sensed events are pertinent. Refractory sensed events are included on Marker Channel recordings.

Pacemaker timing

Refractory periods

Post-Ventricular Atrial Refractory Period

The Post-Ventricular Atrial Refractory Period (PVARP) follows a paced, sensed, or refractory sensed ventricular event when the pacemaker is operating in the DDDR, DDD, DDIR, DDI, and VDD modes. It is intended primarily to prevent the sensing of retrograde P waves that might promote Pacemaker-Mediated Tachycardias (PMTs) in atrial tracking modes. When the pacemaker is operating in the DDIR and DDI modes, PVARP prevents atrial inhibition from retrograde P waves.

The first portion of the PVARP is the programmable Post-Ventricular Atrial Blanking period (PVAB). During the remainder of the PVARP, intrinsic atrial events may be sensed as refractory sensed events (AR) and identified on Marker Channel recordings, but they do not affect stimulus timing.

■

When the pacemaker is operating in the DDDR, DDD, and VDD modes, an SAV is not started.

■

When the pacemaker is operating in the DDDR, DDD, DDIR, and DDI modes, the scheduled atrial pace is not inhibited.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 3

Refractory periods

Figure 3-10. Example of PVARP operation

The duration of the PVARP may be selected as follows:

■

Sensor-varied PVARP

When sensor-varied PVARP is programmed, the pacemaker determines a value for the PVARP based on the sensor-indicated rate. The intended purpose of the sensor-varied PVARP depends upon the mode:

■

PVARP

DDD

The PVARP should be programmed to a value greater than the patient’s ventriculoatrial (VA) retrograde time when retrograde conduction is present.

Excessively long PVARPs may induce 2:1 block at high intrinsic rates when the pacemaker is operating in an atrial tracking mode (DDDR, DDD, or VDD).

To reduce the 2:1 block point, PVARP can be set to vary based on the sensor-indicated rate (sensor-varied PVARP) or the mean atrial rate (automatic PVARP).

When the pacemaker is operating in the DDDR, DDD, and VDD modes, sensor-varied PVARP is intended to do the following:

– Enhance protection against PMT at lower rates by

providing longer PVARPs at low sensor-indicated rates.

– Allow tracking of higher atrial rates (that is, provide a higher

2:1 block rate) by shortening the PVARP at high sensor-indicated rates.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Upper

Sensor

Rate

Lower

Rate

Pacemaker timing

Refractory periods

■

When the pacemaker is operating in the DDIR mode, the sensor-varied PVARP is intended to promote AV synchrony by preventing inhibition of atrial pacing by an atrial sense early in the VA interval. It also reduces the likelihood of competitive atrial pacing at high sensor-indicated rates.

400 ms 300 ms 400 ms

PAV PVARP PAV PVARP

Figure 3-11. Sensor-varied PVARP operation (DDDR Mode)

Determining sensor-varied PVARP

The pacemaker determines the duration of the sensor-varied PVARP as follows:

■

When the pacemaker is operating in the DDDR, DDD, and VDD modes, the sensor-varied PVARP is limited to 400 ms at low rates and the programmed PVAB at high rates (as shown in Figure 3-11).

■

When the pacemaker is operating in the DDIR mode, the sensor-varied PVARP is approximately 400 ms at low rates and the programmed PVAB at high rates.

■

When the pacemaker is operating in the DDDR, DDD, DDIR, and VDD modes, the sensor-varied PVARP is automatically adjusted to maintain a 300 ms sensing window (as shown in Figure 3-11).

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

200 ms

Chapter 3

Refractory periods

Automatic PVARP

Determining automatic PVARP

When automatic PVARP is programmed, the pacemaker determines a value for the PVARP based on the mean atrial rate (which is an average of all A-A intervals except those starting with an atrial sense or atrial refractory sense and ending with an atrial pace). When the pacemaker is operating in the DDDR, DDD, and VDD modes, automatic PVARP is intended to provide a higher 2:1 block rate by shortening the PVARP and SAV (if necessary) at higher tracking rates and protect against PMTs at lower rates by providing a longer PVARP.

The pacemaker determines the duration of the automatic PVARP as follows:

■

After every four pacing cycles, a 2:1 block rate is calculated that is 30 min

■

PVARP is then adjusted so the total atrial refractory period

-1

above the current mean atrial rate.

equals the calculated 2:1 block rate. The programmable Minimum PVARP parameter controls the minimum value that PVARP can be shortened to.

■

If the minimum PVARP value is reached and the 2:1 block rate is still too low, the SAV interval can be shortened to increase the 2:1 block rate. The minimum SAV that can be set is the rate adaptive SAV value (i.e., the programmed SAV value minus the RAAV Maximum Offset value).

The minimum adjustable 2:1 block rate is 100 min

-1

. The maximum adjustable 2:1 block rate is the Upper Tracking Rate plus 35 min

-1

. If Mode Switch is On, the maximum 2:1 block rate can be the Detect Rate if this rate is less than the Upper Tracking Rate calculation.

Programming restrictions for automatic PVARP

Rate Drop Response – Automatic PVARP is not available when

Rate Drop Response is programmed On.

Spontaneous PVARP extension

The programmed PVARP duration, the sensor-varied PVARP, and the automatic PVARP may be overridden by the PVC Response and PMT Intervention features, as follows:

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

■

When the PVC Response feature is programmed On and a pacemaker-defined PVC occurs, the PVARP is forced to 400 ms for one cycle if a lesser value is in effect.

■

When PMT Intervention is programmed On and a pacemaker-defined PMT is detected, the PVARP is forced to 400 ms for one cycle after the ninth paced ventricular event of the PMT.

Refer to “PMT intervention” on page 150 and “PVC Response” on page 153 for further details on the PMT Intervention and PVC Response features and their interactions with PVARP.

Total Atrial Refractory Period (TARP)

In dual chamber modes that sense in the atrium, the Total Atrial Refractory Period (TARP) is the sum of two intervals, as follows:

AV Interval – The AV interval begins with an atrial event and ends with a ventricular event. The first portion is a nonprogrammable blanking period. Its complete duration is determined as follows:

■

When the pacemaker is operating in the DDDR, DDD, and VDD modes, the PAV or SAV interval is the AV interval.

■

When the pacemaker is operating in the DDIR and DDI modes, the AV interval starts with the first atrial sensed event in the VA interval or with an atrial pacing stimulus; it ends when the PAV expires, even when ventricular pacing is inhibited.

Pacemaker timing

Refractory periods

Post-Ventricular Atrial Refractory Period (PVARP) – The PVARP is described on page 75.

TARP TARP

SAV + PVARP

SAV

Figure 3-12. Total Atrial Refractory Period

PVARP

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

SAV

PVARP

Chapter 3

Refractory periods

Ventricular Refractory Period

During atrial tracking, TARP = SAV + PVARP, and its duration determines the rate at which 2:1 block occurs. Refer to “High rate atrial tracking” on page 84 for more information.

The programmable Ventricular Refractory Period (VRP) follows paced, sensed, and refractory sensed ventricular events (including PVCs) in all dual chamber and ventricular modes that sense in the ventricle. The VRP is intended to prevent sensing of the T wave or a PVC. The first portion of the VRP is a nonprogrammable blanking period. A ventricular refractory sensed event affects pacemaker timing as follows:

■

Ventricular blanking and refractory periods restart in all modes.

■

When the pacemaker is operating in the DDDR, DDD, and VDD modes, the upper tracking rate interval, PVARP, and PVAB also restart.

■

When the pacemaker is operating in the VVIR and VDIR modes, the upper sensor rate interval restarts.

Note: In dual chamber modes, the VRP should be programmed shorter than the PVARP.

DDD

Figure 3-13. Example of Ventricular Refractory Period operation

In dual chamber modes, a ventricular refractory sensed event does not affect a scheduled sensor-driven or lower rate atrial output. Thus, a sensor-driven atrial output pulse will initiate a PAV with a ventricular output pulse following, unless inhibited.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

VRP

Atrial Refractory Period (single chamber)

The programmable Atrial Refractory Period (ARP) follows paced, sensed, and refractory sensed atrial events. The ARP is used in the AAIR, ADIR, AAI, ADI, and AAT modes. It is intended to prevent inhibition due to far-field R wave sensing. The first portion of the ARP is a programmable blanking period. The ARP should be programmed to a value long enough (180 ms or greater) to prevent far-field R wave sensing but short enough to ensure atrial sensing up to the programmed Upper Sensor Rate.

If the pacemaker is programmed to an MVP mode (AAIR<=>DDDR or AAI<=>DDD) and is operating in AAIR or AAI mode, the ARP is automatically adjusted to 75% of the cardiac cycle length, up to a maximum of 600 ms.

Noise reversion

When sensing occurs during the Atrial Refractory Period (ARP) or Ventricular Refractory Period (VRP), the refractory period (and its blanking period) are restarted. The operation associated with continuous refractory sensing in the ARP or VRP is called noise reversion. Multiple restarts of the ARP or VRP (continuous noise reversion) do not inhibit scheduled pacing. Pacemaker behavior during continuous noise reversion is as follows:

■

Pacing occurs at the sensor-indicated rate for all rate responsive modes (except VVIR and VDIR).

■

Pacing occurs at the programmed Lower Rate for all non-rate responsive modes (including VVIR and VDIR).

Pacemaker timing

Refractory periods

On the ECG, noise reversion may be difficult to distinguish from loss of sensing, but Marker Channel recordings will show refractory sense markers when noise reversion occurs.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 3

Refractory periods

Sensor-Indicated Interval

Sensor Sensor Sensor

DDDR

P R R R

Parameters: Lower Rate = 60 min

PAV Interval = 200 ms Ventricular Refractory Period = 240 ms

PVARP = 300 ms PVAB = 200 ms

-1

(1000 ms) Upper Sensor Rate = 120 min-1 (500 ms)

Figure 3-14. Example of noise reversion in DDDR at sensor-indicated rate.

Note: If an atrial refractory sensed event occurs, the pacemaker

does not restart the refractory period. However, an atrial refractory sensed event will start a short blanking period of 50 to 100 ms depending on the signal strength and duration of the atrial event.

Lower Rate

VVIR

R R R R P

Sensor

Parameters: Lower Rate = 60 min

Upper Sensor Rate = 120 min

-1

(1000 ms) Ventricular Refractory Period = 240 ms

-1

(500 ms)

Sensor

200 ms

Figure 3-15. Example of noise reversion in VVIR at lower rate.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Preventing noise sensing

Noise reversion may be caused by electromagnetic interference (EMI), myopotentials, excessively high output settings, or low sensitivity settings. When it has been identified, noise reversion usually can be reduced or eliminated by one of the following actions:

■

Reprogram sensitivity to a less sensitive setting (higher numerical value) or program Sensing Assurance to On, to monitor and if necessary, adjust the sensitivity value. Refer to “Sensing Assurance and diagnostic” on page 118.

■

Reprogram sensing polarity to bipolar polarity (if available).

■

Reduce the amplitude and/or pulse width in the same or opposite chamber.

■

Program Capture Management to Adaptive to monitor capture thresholds, and, if necessary, adjust amplitude and pulse width values. Refer to “Capture Management and diagnostic” on page 98.

■

Remove patient from EMI environment.

Pacemaker timing

Refractory periods

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 3

High rate atrial tracking

Overview

2:1 block

When the pacemaker is operating in the DDDR, DDD, and VDD modes, the fastest atrial rate the pacemaker can track is determined by the total atrial refractory period (TARP), which is the sum of the SAV and the PVARP. Pacemaker behavior at high atrial rates in these modes is determined by the relationship between the TARP and the interval corresponding to the Upper Tracking Rate. In the DDDR mode, the interval corresponding to the Upper Sensor Rate also must be considered.

When the intrinsic atrial interval is shorter than the TARP, some atrial events will fall in the PVARP and not be tracked. At the rate where this first occurs, ventricular tracking occurs only on alternate beats, and 2:1 block ensues. When the pacemaker is operating in the DDD and VDD modes, the ventricular pacing rate drops precipitously.

■

When sensor-varied PVARP or automatic PVARP is selected, the 2:1 block rate may occur at a higher rate during activity due to shortening of the PVARP and the SAV (automatic PVARP only), thus increasing atrial tracking.

■

When Rate Adaptive AV operation is selected, the SAV shortens at high atrial rates, shortening the TARP and raising the 2:1 block rate.

■

When the 2:1 block rate is less than the Upper Tracking Rate, the Upper Tracking Rate cannot be achieved.

■

When the pacemaker is operating in DDDR mode, pacing at the sensor-indicated rate may prevent a precipitous rate drop at the 2:1 block point when activity is present.

■

For patients with a documented propensity for prolonged or sustained atrial fibrillation or flutter, the clinician can select Upper Tracking Rate, SAV, and PVARP values that induce 2:1 block at a desired rate (2:1 block rate = 60,000/TARP). Alternatives for controlling rates in these patients include use of the Mode Switch feature and DDIR mode pacing.

■

When the pacemaker is operating in the DDDR mode, atrial competition may occur if the Upper Sensor Rate exceeds the 2:1 block rate.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Pacemaker Wenckebach

When the 2:1 block rate exceeds the programmed Upper Tracking Rate, pacemaker Wenckebach may occur. When the intrinsic rate exceeds the Upper Tracking Rate, a pacing stimulus at the expiration of the SAV would violate the upper tracking rate. The pacemaker therefore extends the SAV until the upper tracking rate interval expires. Subsequent SAVs require greater extension, until an atrial event falls in the PVARP and is not tracked.

■

When the pacemaker is operating in the DDDR, DDD, and VDD modes, the result is normally a fixed ratio between atrial and ventricular rates (3:2, 4:3, and so forth).

■

When the pacemaker is operating in the DDDR mode, the pacemaker Wenckebach rate may be smoothed by sensor-driven ventricular pacing, thereby overriding the fixed ratio.

Figure 3-16 shows how pacemaker Wenckebach operation occurs in the DDDR, DDD, or VDD modes.

Pacemaker timing

High rate atrial tracking

Upper Tracking

Rate Interval

DDDR

Parameters: Sensor-Indicated Rate = 90 min

PAV Interval = 230 ms Upper Tracking Rate = 100 min

SAV Interval = 200 ms

Upper Tracking

Rate Interval

-1

(667 ms) PVARP = 300 ms

Upper Tracking

Rate Interval

SAV

Interval

Figure 3-16. Example of pacemaker Wenckebach operation

Sensor

-1

(600 ms)

200 ms

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 3

High rate atrial tracking

High rate operation in the DDDR mode

Table 3-1 summarizes how the total atrial refractory period (TARP), the Upper Tracking Rate (UTR) interval, and the Upper Sensor Rate (USR) interval may interact at high atrial rates when the pacemaker is operating in the DDDR mode.

Tab le 3- 1. Upper rates interaction with TARP

Relationship Between TARP and Upper Rate Intervals

TARP > both USR and UTR intervals

USR interval > TARP > UTR interval

USR interval > UTR interval > TARP

UTR interval > both USR interval and TA RP

Unless the Non-Competitive Atrial Pacing is On, see “Non-competitive atrial pacing” on page 148.

Wenckebach

Before 2:1

Block

Achieve

Upper

Tracking

Rate

no no yes

no no no

yes yes no

yes yes yes

Potential

Atrial

Competition

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Lead/cardiac tissue interface4

Implant Detection 88

Automatic polarity configuration 89

Lead Monitor 94

Lead impedance data 97

Capture Management and diagnostic 98

Sensing Assurance and diagnostic 118

Manually selecting pacing parameters 122

Manually selecting sensing parameters 125

Transtelephonic follow-up features 129

Chapter 4

Implant Detection

Overview

Implant Detection is a 30-minute period, beginning at lead connection, during which the pacemaker verifies that each lead has been connected by measuring lead impedance. After 30 minutes of continuous lead connection, the pacemaker completes Implant Detection and activates the following features (see Figure 4-1):

■

Operating polarity (automatic configuration occurs during Implant Detection)

■

MVP operations including conduction checks and mode changes

■

Adaptive sensitivity settings (Sensing Assurance)

■

Rate responsive pacing, including adaptive rate profile optimization (Rate Profile Optimization)

■

Adaptive ventricular output settings for threshold management (Capture Management)

■

Diagnostic data collection

Lead Connection verified

Implant

Leads connected

Figure 4-1. Implant Detection period

Implant Detection is available in all pacing modes and is turned on at shipment.

Note: Search AV+ initializes 60 min after Implant Detection is complete.

Note: Automatic polarity configuration does not occur during Implant Detection if the Lead Monitor parameter is programmed to Monitor Only before implant. Automatic configuration will take place if Lead Monitor is programmed to Adaptive before implant or remains set to its shipping setting of Configure.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

30 Minutes

Lead polarities confirmed

Rate Response enabled

Adaptive features activated

Data collection activated

Lead/cardiac tissue interface

Automatic polarity configuration

Verifying lead connection during Implant Detection

At the time of lead connection, the pacemaker begins verifying that each lead is present by measuring the impedance of each pacing pulse. When a pace is delivered, the pacemaker determines if the impedance is within the acceptable range, which is programmable between 200 to 4000

ohms for both bipolar and unipolar

configurations.

■

High impedance paces cause Implant Detection to reset.

■

Low impedance paces (and continuous sensing) are considered acceptable for the purpose of determining lead connection and configuring polarity.

Automatic polarity configuration

Overview

During Implant Detection, bipolar pacemakers automatically configure pacing and sensing polarities through the Lead Monitor feature. Bipolar pacemakers are shipped with the Atrial and Ventricular Lead Monitor set to Configure, enabling automatic polarity determination shortly after lead connection.

Unipolar-only pacemakers are configured to unipolar pacing and sensing polarity at the time of manufacture and remain unipolar during the operational life of the pacemaker.

The acceptable maximum impedance limit for a valid lead (bipolar or unipolar) can be changed by programming the Notify If > (Greater Than) parameter, which is part of the Lead Monitor and is found under the programmed lead polarities. The minimum impedance limit of 200 ohms is nonprogrammable.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 4

Automatic polarity configuration

Measuring lead impedance during configuration

Bipolar pacemakers, using either bipolar or unipolar leads, automatically configure pacing and sensing polarities by measuring the impedance of each pace during the configuration period. (Lead Monitor must be set to Configure or Adaptive. See “Lead Monitor” on page 94.) Impedance measurement during configuration is as follows:

■

The pacemaker issues a bipolar pace and immediately checks the pace for high impedance.

– If the pace is within range, it is considered an acceptable

bipolar pace.

– If high impedance is found, the pacemaker immediately

follows the bipolar pace with a backup unipolar pace.

■

If a unipolar backup pace is issued, the pacemaker checks it for high impedance.

– If the pace is within range, it is considered an acceptable

unipolar pace.

– If high impedance is found, the pacemaker assumes a lead

is not attached and restarts Implant Detection.

Notes:

■

During polarity configuration, the pacemaker also detects low impedance paces but does not follow them with unipolar backup paces. To avoid possible loss-of-capture due to continuous low impedance pacing, the pacemaker sets unipolar polarity when 3 of 16 paces are detected as low impedance during the first phase of configuration (see “Initial Configuration Phase” on page 91).

■

If the pacemaker assumes a lead is not present (a high impedance unipolar pace is detected) in one chamber of a dual chamber pacemaker, Implant Detection will restart.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

How polarities are automatically configured

Atrial and ventricular lead polarities are configured independently in dual chamber bipolar models, with the exception of pacemakers in the VDD Series, which have fixed bipolar atrial sensing only.

Operating pacing and sensing polarities for bipolar pacemakers are configured automatically in two phases during Implant Detection. (See Figure 4-2.) During these phases the pacemaker continues to measure impedance as described above.

Implant Detection

Confirmation PhaseInitial Configuration Phase

Lead/cardiac tissue interface

Automatic polarity configuration

Implant

Leads Connected

Figure 4-2. Automatic configuration of bipolar models

Lead polarities configured

5 Minutes

Initial Configuration Phase – The pacemaker sets lead

polarities five minutes after lead connection unless a high impedance unipolar pace has reset Implant Detection, a prevalence of low impedance bipolar paces has set unipolar pacing, or if continuous sensing has occurred.

The pacemaker sets initial polarities as follows:

■

The pacemaker delivers three asynchronous paces at magnet rate.

■

If at least two of the three paces are determined to be bipolar, the pacemaker remains set to bipolar polarity (with backup unipolar paces) for the Confirmation Phase.

■

If at least two of the three paces are determined to be unipolar, the pacemaker sets polarity to unipolar. Unipolar polarity becomes the operating polarity for pacing and sensing, and no Confirmation Phase is required.

Note: If one of the asynchronous paces in a given chamber is a high impedance unipolar pace, the pacemaker restarts Implant Detection in both chambers. Polarity configuration restarts only in the affected chamber, however.

30 Minutes

Lead polarities

confirmed

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 4

Automatic polarity configuration

Confirmation Phase – Twenty-five minutes after initial configuration, the pacemaker confirms final operating polarity for leads configured bipolar in the Initial Configuration Phase. During this 25-minute Confirmation Phase, the pacemaker measures the lead for high and low impedance paces. If 8 of 16 paces (or the programmed number of paces out of sixteen) are out of range, the lead will automatically be reconfigured to unipolar polarity.

At the end of twenty-five minutes, operating polarity for leads detected as bipolar during the Initial Configuration Phase is determined as follows:

■

The pacemaker delivers three asynchronous paces at magnet rate.

■

If at least two of the three paces are determined to be bipolar, the pacemaker sets operating polarity to bipolar (or Adaptive operation if Lead Monitor was programmed to Adaptive prior to implant). See “Lead Monitor” on page 94.

■

If at least two of the three paces are determined to be unipolar, the pacemaker sets operating pace and sense polarities to unipolar.

Note: If a high impedance unipolar pace occurs in a given chamber at any time during the 25-minute Confirmation Phase, the pacemaker restarts Implant Detection in both chambers. Polarity configuration restarts only in the affected chamber, however.

Leads configured unipolar during the Initial Configuration Phase continue to operate in the unipolar configuration. If bipolar polarity switches to unipolar during the Confirmation Phase, the operating polarity remains unipolar with no additional confirmation through asynchronous pacing.

Warning: If, at implant, the setscrews, both tip and ring, for a

3.2 mm connector pacemaker are not properly engaged and all electrical contacts are not sealed, leakage between the tip and ring contacts may occur. Such leakage may cause the pacemaker to falsely identify a unipolar lead as bipolar, resulting in a loss of output. The same result could occur for all bipolar models if the electrical contacts were not properly sealed when using lead extenders or adaptors.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

When automatic configuration is complete

Thirty minutes after lead connection, Implant Detection and automatic configuration are complete. If, after this time period, the leads are detached and lead polarity type is changed, automatic configuration and Implant Detection do not restart automatically at reinsertion. The clinician must reprogram Implant Detection to On/Restart, which automatically resets Lead Monitor to Configure.

The Lead Monitor feature (see “Lead Monitor” on page 94) monitors and reports on lead stability when Implant Detection and automatic configuration are complete. It is automatically set by the pacemaker as follows:

■

Bipolar models are shipped with Lead Monitor set to Configure. However, after Implant Detection ends, Lead Monitor is automatically set to Monitor Only for bipolar and unipolar configurations.

■

Bipolar models with Lead Monitor programmed to Adaptive before implant are set to Adaptive if polarity was determined to be bipolar. If polarity for these models was determined to be unipolar, they are set to Monitor Only.

■

Unipolar models are shipped with Lead Monitor set to Monitor Only and continue to operate at that setting both during and after Implant Detection.

Lead/cardiac tissue interface

Automatic polarity configuration

Manually setting polarities

To manually program atrial or ventricular lead polarities at implant, the clinician first must “turn off” the Configure setting under Lead Monitor by choosing the Monitor Only setting instead. Implant Detection still provides the 30-minute detection period, followed by automatic feature and diagnostics activation, when the pacemaker is programmed manually.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 4

Lead Monitor

Programming interactions

Lead Monitor

■

Programming Implant Detection to Off /Complete before completion of the 30-minute automatic polarity configuration period requires the clinician to manually program Lead Monitor and polarities. The pacemaker’s automatic features are activated when Implant Detection is turned off.

■

Manually programming Implant Detection to On/Restart restarts lead detection, polarity configuration (Lead Monitor is set to Configure), and automatic feature activation.

■

Initiating a programming session at any time during Implant Detection causes Implant Detection to be restarted.

■

If a dual chamber pacemaker is programmed to a single chamber mode, only one lead is configured. If the mode is reprogrammed to a dual chamber mode, the clinician will need to change the Lead Monitor from Configure to Monitor Only or Adaptive for the unconfigured lead, and then program pace and sense polarity for it manually.

Overview

The Lead Monitor feature measures lead impedances during the life of the pacemaker. When programmed to do so, Lead Monitor also enables the pacemaker to switch bipolar pacing and sensing to unipolar when bipolar lead integrity is in doubt. It also controls automatic configuration of lead polarities at implant. Lead Monitor is available in all pacing modes.

Caution: If the Lead Monitor detects out-of-range lead impedance, investigate lead integrity more thoroughly.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

How lead monitoring works

The Lead Monitor feature monitors lead impedance of paced chambers, as defined by the mode, by measuring the impedance of each pacing pulse to see if it falls within the programmed impedance range for a stable lead.

The three programmable values under Atrial or Ventricular Lead Monitor are as follows:

■

Configure - provides automatic configuration of polarity (see “How polarities are automatically configured” on page 91).

■

Adaptive

– monitors bipolar paces for high impedance and provides

unipolar backup paces when high impedance is detected.

– switches pacing and sensing polarity from bipolar to

unipolar when the pacemaker detects a prevalence of high or low impedance paces (see Monitor Sensitivity parameter in Table 4-1). The Lead Monitor setting changes to Monitor Only when polarity switches.

– provides automatic polarity configuration when selected

prior to implant.

■

Monitor Only - monitors either unipolar or bipolar paces to determine if they are out of range but does not switch polarity when an out-of-range lead is indicated.

Lead/cardiac tissue interface

Lead Monitor

Lead Monitor is activated at lead connection, and it is automatically set to its operating value of Monitor Only or Adaptive at the end of Implant Detection. See “When automatic configuration is complete” on page 93.

When Lead Monitor is set to Adaptive or Monitor Only and a lead is determined to be out of range, the pacemaker issues a lead warning that appears on the programmer screen at the next interrogation.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 4

Lead Monitor

Lead Monitor programmable parameters – The programmable parameters for the Lead Monitor feature are shown below.

Tab le 4- 1. Programmable parameters for Lead Monitor

General Parameters Meaning

Atrial Lead Monitor Monitors lead impedance in the atrium;

Ventricular Lead Monitor

Notify If < (Less Than) Nonprogrammable minimum boundary for

Notify If > (Greater Than)

Monitor Sensitivity Number of high or low impedance paces out

option to provide unipolar backup paces and to switch from bipolar to unipolar polarity for an out-of-range lead; provides automatic configuration of polarity at implant.

Monitors lead impedance in the ventricle; option to provide unipolar backup paces and to switch from bipolar to unipolar polarity for an out-of-range lead; provides automatic configuration of polarity at implant.

acceptable atrial and ventricular bipolar lead impedance. Fixed at 200 ohms.

Maximum boundary for acceptable atrial and ventricular bipolar lead impedance.

of 16 that define an out-of-range lead on each channel.

Lead Monitor should not be programmed to Adaptive for patients with implantable defibrillators. When a prevalence of out-of-range lead impedance paces is detected, the monitor automatically reprograms the selected lead(s) to unipolar polarity. Pacing in the unipolar configuration may cause the defibrillator either to provoke inappropriate therapy or to withhold appropriate therapy.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Lead/cardiac tissue interface

Lead impedance data

Lead impedance data is recorded automatically.

Automatic Lead Impedance (Chronic Lead Trend)

The automatic Lead Impedance diagnostic data is based on measurements taken every three hours for each chamber that is being paced. The maximum, average, and minimum lead impedances are recorded every seven days for the most recent 14 months.

The following data is continuously updated:

■

Initial impedance (recorded at implant or when Chronic Lead Trend is cleared)

■

Lifetime minimum impedance (recorded since implant)

■

Lifetime maximum impedance (recorded since implant)

■

High impedance paces

■

Low impedance paces

Lead impedance data

If the maximum number of high impedance paces or low impedance paces is reached, that value will remain until the data is cleared. All other diagnostic data collection will continue.

Note: To avoid high output pacing, Chronic Lead Trend data collection can be programmed to Off. The outputs are increased to make lead impedance measurements every 3 hours.

Clearing Lead Impedance data

Automatic (Chronic) Lead Impedance Trend data is retained by the pacemaker unless you use the Clear Data function on the programmer. Note that the data should be cleared only when a lead is replaced. Be sure to save the session data or print the trend report before ending the patient session.

For further information

Refer to the Adapta/Versa/Sensia/Relia Pacemaker Programming Guide for information about collecting and displaying lead

impedance trends.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Chapter 4

Capture Management and diagnostic

Overview

When Capture Management is enabled, the pacemaker automatically monitors pacing thresholds at periodic intervals. Once the threshold is determined, the pacemaker determines a target output based on the programmable safety margin and programmable minimum amplitude.

■

If programmed to Adaptive, the pacemaker reprograms outputs toward the target.

■

If programmed to Monitor Only, the pacemaker does not reprogram outputs.

Caution: Epicardial leads have not been determined appropriate for use with the Ventricular Capture Management feature. Program Ventricular Capture Management to Off if implanting an epicardial lead.

Note: The pacemaker enables Capture Management once Implant Detection is completed.

Note: In the event of partial or complete lead dislodgment, Capture Management may not prevent loss-of-capture.

Ventricular Capture Management (VCM)

At programmable intervals, the pacemaker performs a ventricular pacing threshold search to determine the ventricular threshold, which is the combination of minimum amplitude and minimum pulse width that consistently results in capture of the ventricular myocardium.

Atrial Capture Management (ACM)

At programmable intervals, the pacemaker performs an atrial pacing threshold search to determine the atrial amplitude threshold, which is the minimum amplitude that consistently results in capture of the atrial myocardium.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Lead/cardiac tissue interface

Capture Management and diagnostic

Initiating the pacing threshold search

Scheduling the search – A pacing threshold search is initiated

according to the schedule programmed by the clinician. The Capture Test Frequency parameter under Capture Management allows the clinician to schedule the search at fixed time intervals. (Refer to Table E-5 on page E-307 for the programmable time intervals for the pacing threshold search.) The clinician can also program the Day At Rest value that allows the pacemaker to determine when to run the search.

If a pacing threshold search is scheduled to occur once per Day At Rest, the pacemaker tries to initiate the first pacing threshold search 12 hours after Implant Detection is complete. It then runs subsequent searches at 24-hour intervals from the time of the last successfully completed search.

If a search cannot be completed, the pacemaker retries after 30 minutes.

Programmable Capture Management parameters

Capture Management can be programmed to Adaptive, Monitor Only, or Off. When Capture Management is programmed to Adaptive, the parameters in Table 4-2 are used to control Capture Management operation. They can also be programmed for diagnostic use when Capture Management is programmed to Monitor Only.

Tabl e 4 -2 . Programmable parameters for Capture Management

General parameters

Amplitude Margin The safety margin applied to the pacing

Minimum Adapted Amplitude

Capture Test Frequency

V. Acute Phase Days Remaining

Meaning

threshold search results for Amplitude.

The lower limit to which the operating Amplitude can be adapted.

Determines how often the pacing threshold search will be initiated.

Time in days during which output settings can be adapted both upward and downward, but not below the permanently programmed ventricular outputs.

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

100

Chapter 4

Capture Management and diagnostic

Tab le 4- 2. Programmable parameters for Capture Management

General parameters

A. Acute Phase Days Remaining

Meaning

Time in days during which output settings can be adapted both upward and downward, but not below the permanently programmed atrial outputs.

V. Sensing During Search

The polarity used for ventricular sensing during ventricular pacing threshold searches. See “Preventing undersensing of ventricular evoked response events during the search” on page 107.

Ventricular Capture Management (VCM)

Checking for stable rhythm – Before a pacing threshold search

can be initiated, the pacemaker determines if the patient is pacing or sensing at a low rate. A low rate is desirable during the pacing threshold search to reduce the risk of competition from forced pacing with fast intrinsic rhythms. To make the determination, the pacemaker looks for intrinsic or rate related events indicating:

■

Out of eight measured V-V intervals no more than two are faster than:

–100min

are ≥ 135 min

–95min-1 if the upper sensor rate and upper tracking rate are

≥ 125 min

–90min-1 if the upper sensor rate and upper tracking rate are

< 125 min

■

the sensor rate, checked at the end of the eight intervals, is at or below the ADL rate.

■

in dual chamber modes, at least one valid AV interval (AS-VS, AS-VP, AP-VS, AP-VP) occurred during the eight measured intervals.

-1

if the upper sensor rate and upper tracking rate

-1

The pacemaker also looks for automatic feature interaction indicating:

■

Rate Drop Response is not in an intervention state.

■

Mode Switch is not changing between a tracking and a nontracking mode.

■

Battery measurements

Adapta/Versa/Sensia/Relia Pacemaker Reference Guide

Medtronic ADDR01, ADDRS1, ADDR03, ADDR06, ADDRL1 Pacemaker Reference Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

1 Pacing modes 13

2 Rate response 35

3 Pacemaker timing 55

4 Lead/cardiac tissue interface 87

5 Special therapy options 133

6 Telemetry data 175

7 Miscellaneous operations 187

8 Diagnostics 195

9 Troubleshooting the pacing system 221

A Pacemaker description 231

B Preset parameter settings 237

C Longevity projections 265

D Telemetry and diagnostic values 285

E Parameter values and restrictions 299

F Implant information 317

G Glossary 333

How to use this guide

Information is contained in two guides

About the Pacemaker Reference Guide

About the Pacemaker Programming Guide

The Implant Manuals supplement these guides

New nomenclature for product battery life terms

Pacing modes1

Introduction

Pacing mode selection

NBG pacing codes

Rationale for mode selection

Further information

Indications

Contraindications

MVP modes

DDDR mode

DDD mode

DDIR mode

DDI mode

DVIR mode

DVI mode

VDD mode

AAIR / ADIR modes

AAI / ADI modes

VVIR / VDIR modes

VVI / VDI modes

AAT / VVT modes

DOOR / AOOR / VOOR modes

DOO / AOO / VOO modes

ODO / OAO / OVO modes

Rate response2

Introduction to rate responsive pacing

Rate response

Automatic features

For further information

Preset rate response at implant

Overview

Three pacing rate controls

Starting rate response immediately

For further information

Rate Profile Optimization operation

Overview

Rate control in the ADL and exertion rate ranges

Optimization using rate profiles

Daily optimization of rate response

Adaptations in Optimization operation

Individualizing Rate Profile Optimization

Overview

ADL rate profiles

Exertion rate profiles

Programming guidelines

Activity sensor operation

Overview

How Activity Threshold influences rate

Evaluating the Activity Threshold setting

How Activity Acceleration and Deceleration influence rate

Exercise Deceleration operation

Manual control of Rate Profile Optimization

Overview

Evaluate and program rate response