Medtronic 7232CX Reference Guide
MAXIMO™ VR 7232Cx, 7232B,
7232E
Single Chamber Implantable Cardioverter Defibrillator (VVE-VVIR)
Reference Manual
Caution: Federal Law (USA) restricts this device to sale by or on
the order of a physician (or properly licensed practitioner).
MAXIMOTM VR 7232Cx,
7232B, 7232E
Reference Manual 0
A guide to the operation and programming of the Model
7232Cx, 7232B, and 7232E MaximoTM VR Single Chamber
Implantable Cardoverter Defibrillator
0
The following are trademarks of Medtronic:
Active Can, Cardiac Compass, Checklist, Decision Channel, Flashback, GEM,
Leadless ECG, Marker Channel, Maximo, Patient Alert, Quick Look, QuickLink,
RapidRead, T-Shock, Wavelet
Table of contents
Introduction 11
Abbreviations and acronyms 13
Part I Quick overview
1 Quick reference 17
Physical characteristics 18
Magnet application 22
Longevity projections 23
Replacement indicators 26
Typical charge times 27
High-voltage therapy energy 27
Stored data and diagnostics 29
New and enhanced features 31
2 The Maximo VR system 37
System overview 38
Indications and usage 41
Contraindications 41
Patient screening 41
Table of contents
5
3 Emergency therapy 43
Delivering emergency therapies 44
Part II Device implant and patient follow-up procedures
4 Implanting the ICD 53
Overview 54
Preparing for an implant 54
Replacing an ICD 57
Positioning the leads 58
Testing sensing and pacing thresholds 60
Connecting the leads to the ICD 61
Testing defibrillation operation and effectiveness 65
Positioning and securing the ICD 67
Maximo VR 7232Cx, 7232B, 7232E Reference manual
6
Table of contents
Completing the implant procedure 68
5 Conducting a patient follow-up session 69
Patient follow-up guidelines 70
Verifying the status of the implanted system 70
Verifying accurate detection and appropriate therapy 71
Verifying effective bradycardia pacing 73
Part III Configuring the ICD for the patient
6 Detecting tachyarrhythmias 77
Detection overview 78
Setting up sensing 81
Detecting VF episodes 85
Detecting VT episodes 90
Detecting FVT episodes 96
Detecting tachyarrhythmia episodes with Combined Count 101
Monitoring episodes for termination or redetection 104
Enhancing detection with Wavelet 107
Enhancing VT detection with the Onset criterion 116
Enhancing VT detection with the Stability criterion 121
Detecting prolonged tachyarrhythmias with
High Rate Timeout 124
Key terms 126
7 Treating tachyarrhythmia episodes 131
Treating VF with defibrillation 132
Treating VT and FVT with antitachycardia pacing 143
Treating VT and FVT with cardioversion 153
Optimizing therapy with Smart Mode and Progressive Episode
Therapies 161
Key terms 166
8 Treating bradycardia 169
Providing basic pacing therapy 170
Enhancing pacing for optimal cardiac output 174
Providing pacing after high-voltage therapies 185
Key terms 186
Maximo VR 7232Cx, 7232B, 7232E Reference manual
Table of contents
9 Optimizing charge time and device longevity 189
Optimizing charge time 190
Optimizing device longevity 193
Key terms 194
Part IV Evaluating and managing patient treatment
10 Using the programmer 197
Setting up and using the programmer 198
Display screen features 199
Viewing and programming device parameters 206
Starting and ending patient sessions 210
Viewing live waveform traces 212
Recording live waveform strips 219
Saving and retrieving device data 221
Printing reports 225
Key terms 230
11 Using system evaluation tools 231
A summary of system evaluation tools 232
Taking a quick look at device activity 233
Using the Patient Alert feature 235
Streamlining follow-ups with Checklist 243
Key terms 246
7
12 Setting up and viewing collected data 247
A summary of data collection 248
Setting up data collection 249
Collecting lead performance data 255
Viewing the episode and therapy efficacy counters 257
Viewing episode data 260
Viewing Flashback Memory 268
Viewing battery and lead status data 270
Viewing lead performance trends 272
Using Cardiac Compass to view long term clinical trends 274
Viewing and entering patient information 279
Automatic device status monitoring 283
Maximo VR 7232Cx, 7232B, 7232E Reference manual
8
Table of contents
Key terms 285
13 Testing the system 289
Testing overview 290
Evaluating the underlying rhythm 291
Measuring pacing thresholds 292
Testing the Wavelet criterion 295
Measuring lead impedance 299
Measuring EGM Amplitude 301
Testing the device capacitors 303
Key terms 305
14 Conducting electrophysiologic studies 307
EP Study overview 308
Inducing VF with T-Shock 310
Inducing VF with 50 Hz Burst 313
Inducing an arrhythmia with Manual Burst 316
Inducing an arrhythmia with PES 318
Delivering a manual therapy 320
Key terms 323
15 Solving system problems 325
Overview 326
Solving sensing problems 327
Solving tachyarrhythmia detection problems 328
Solving tachyarrhythmia therapy problems 330
Solving bradycardia pacing problems 331
Responding to device status indicators 332
Key terms 333
Appendices A Warnings and precautions 337
General warnings 338
Storage and handling 338
Resterilization 339
Device operation 340
Lead evaluation and lead connection 341
Follow-up testing 342
Maximo VR 7232Cx, 7232B, 7232E Reference manual
Explant and disposal 343
Medical therapy hazards 343
Home and occupational environments 345
BDevice parameters347
Emergency settings 348
Detection parameters 349
Therapy parameters 351
Bradycardia pacing parameters 353
System maintenance parameters 354
Data collection parameters 356
System test and EP study parameters 357
Fixed parameters 360
Patient information parameters 361
Programmer symbols 362
Parameter interlocks 364
Index 365
Table of contents
9
Maximo VR 7232Cx, 7232B, 7232E Reference manual
Introduction
Using this manual
Before implanting the ICD, it is strongly recommended that you:
■
Refer to the product literature packaged with the ICD for
information about prescribing the ICD.
■
Thoroughly read this manual and the technical manuals for the
leads used with the device.
■
Discuss the procedure and the ICD system with the patient
and any other interested parties, and provide them with any
patient information packaged with the ICD.
Contacting technical support
Medtronic employs highly trained representatives and engineers
located throughout the world to serve you and, upon request, to
provide training to qualified hospital personnel in the use of
Medtronic products.
11
Introduction
In addition, Medtronic maintains a professional staff of consultants
to provide technical consultation to product users. For medical
consultation, Medtronic can often refer product users to outside
medical consultants with appropriate expertise.
For more information, contact your local Medtronic representative,
or call or write Medtronic at the appropriate address or telephone
number listed on the back cover.
Customer education
Medtronic invites physicians to attend an education seminar on
the complete ICD system. The course includes indications for use,
an overview of ICD system functions, implant procedures, and
patient management.
Maximo VR 7232Cx, 7232B, 7232E Reference manual
12
Chapter
Introduction
References
Notice
The primary reference for background information is Zacouto FI,
Guize LJ. Fundamentals of Orthorhythmic Pacing. In: Luderitz B,
ed. Cardiac Pacing Diagnostic and Therapeutic Tools. New York:
Springer-Verlag; 1976: 212-218.
See these additional references for more background information:
■
Singer I, Ed. Implantable Cardioverter-Defibrillator. Armonk,
NY: Futura Publishing Co. 1994.
■
Singer I, Barold SS, Camm AJ, Eds. Nonpharmacological
Therapy of Arrhythmias for the 21st Century: The State of the
Art. Armonk, NY: Futura Publishing Co. 1998.
■
Estes M, Manolis AS, Wang P, Eds. Implantable
Cardioverter-Defibrillators. New York, NY: Marcel Dekker, Inc.
1994.
■
Kroll MW, Lehmann MH, Eds. Implantable
Cardioverter-Defibrillator Therapy: The Engineering-Clinical
Interface. Norwell, MA: Kluwer Academic Publishers 1996.
This software is provided as an informational tool for the end user.
The user is responsible for accurate input of patient information
into the software. Medtronic makes no representation as to the
accuracy or completeness of the data input into the software.
MEDTRONIC SHALL NOT BE LIABLE FOR ANY DIRECT,
INDIRECT, INCIDENTIAL OR CONSEQUENTIAL DAMAGES TO
ANY THIRD PARTY WHICH RESULTS FROM THE USE OF THE
INFORMATION PROVIDED IN THE SOFTWARE.
Maximo VR 7232Cx, 7232B, 7232E Reference manual
Abbreviations and acronyms
ATP Antitachycardia Pacing
BOL Beginning of Life
bpm beats per minute
CNID Combined (VT and VF) Number of Intervals to Detect
CV Cardioversion
DF/Defib Defibrillation
ECG Electrocardiogram
EGM Electrogram
EOL End of Life
ERI Elective Replacement Indicator
FDI Fibrillation Detection Interval
FTI Fast Ventricular Tachycardia Detection Interval
13
Abbreviations and acronyms
FVT Fast Ventricular Tachycardia
ICD Implantable Cardioverter Defibrillator
J joules
-1
reciprocal minutes; for example, pacing pulses per minute
min
ms milliseconds
mV millivolts
NID Number of Intervals to Detect
NST Non-sustained Tachycardia
PES Programmed Electrical Stimulation
ppm paces or pulses per minute
PVC Premature Ventricular Contraction
RNID Number of Intervals to Redetect
R-R a ventricular interval
Maximo VR 7232Cx, 7232B, 7232E Reference manual
14
Chapter
Abbreviations and acronyms
ST/Sinus Tach Sinus Tachycardia
SVT Supraventricular Tachycardia
TDI Tachycardia Detection Interval
V volts
V- Ve n tr ic ul ar
VF Ventricular Fibrillation
VF NID VF Number of Intervals to Detect
VRS Ventricular Rate Stabilization
VT Ventricular Tachycardia
VT NID VT Number of Intervals to Detect
Maximo VR 7232Cx, 7232B, 7232E Reference manual
Quick overview
Part I
Maximo VR 7232Cx, 7232B, 7232E Reference manual
Physical characteristics 18
Magnet application 22
Longevity projections 23
Replacement indicators 26
Typical charge times 27
High-voltage therapy energy 27
Stored data and diagnostics 29
New and enhanced features 31
Quick reference1
1
Maximo VR 7232Cx, 7232B, 7232E Reference manual
18
Chapter 1
Physical characteristics
Physical characteristics
Tab le 1- 1. ICD physical characteristicsa
Connector type Cx B or E
Volume 39 cc 45 cc
Mass 76 g 81 g
b
H x W x D
Surface area of
68 mm x 51 mm x
15 mm
2
67 cm
74 mm x 51 mm x
15 mm
2
64 cm
device can
Radiopaque IDc
PRN B-type connector PVF
E-type connector PVG
Materials in contact
with human tissue
Titanium / polyurethane /
d
silicone rubber
Battery Lithium silver vanadium
oxide
a
Measurements are nominal values based on CAD (computer aided design)
model measurements and are rounded to the nearest unit.
b
Grommets may protrude slightly beyond the can surface.
c
Engineering series number follows the radiopaque code.
d
These materials have been successfully tested for the ability to avoid biological
incompatibility. The device does not produce an injurious temperature in the
surrounding tissue.
Titanium / polyurethane /
silicone rubber
Lithium silver vanadium
oxide
Tab le 1- 2. Cx-type connector characteristics
General description Device
One IS-1 connector for pacing and
sensing, Two DF-1 connectors for
high-voltage therapy, Active Can
electrode (programmable).
Maximo VR 7232Cx, 7232B, 7232E Reference manual
Port
Connector
Typ e
Software
Name
SVC DF-1 HVX
RV DF-1 HVB
Can — HVA, Can
V IS-1 bipolar
Figure 1-1. Cx-type connector
2
Quick reference
Physical characteristics
1
19
5
3
4
1 Suture holes
2 SVC port (DF-1)
3RV port (DF-1)
4 programmable Active Can
5V port (IS-1)
Tabl e 1-3 . B-type connector characteristics
General description Device
Port
Three 6.5 mm unipolar
high-voltage ports and one
3.2 mm low profile bipolar
pace/sense (IS-1 compatible) port.
HVB 6.5 mm HVB
HVA
HVX
Connector
Typ e
a
6.5 mm HVX
a
6.5 mm HVX
Software
Name
Can — HVA, Can
P/S
bipolar
pace
3.2 mm
bipolar (IS-1
compatible)
sense
a
The HVA and HVX ports are electrically connected and are treated as the HVX
electrode. For more information see “B- and E-type connector pathways” on
page 136.
Maximo VR 7232Cx, 7232B, 7232E Reference manual
20
Chapter 1
Physical characteristics
Figure 1-2. B-type connector
1
2
6
5
3
4
1 Suture holes
2 HVB port (6.5 mm)
3 HVA port (6.5 mm)
4 programmable Active Can
5 HVX port (6.5 mm)
6 P/S port (3.2 mm)
Tab le 1- 4. E-type connector characteristics
General description Device
Port
Connector
Typ e
Software
Name
P+/S 5.0 mm
Two 6.5 mm unipolar high-voltage
ports and two 5 mm unipolar
pace/sense ports.
HVA 6.5 mm HVX
HVB 6.5 mm HVB
a
Can — HVA, Can
P-/S 5.0 mm
a
The HVA port of the E-type connector can be used as the HVX electrode when
Active Can is programmed off. For more information, see “B- and E-type
connector pathways” on page 136.
Maximo VR 7232Cx, 7232B, 7232E Reference manual
Figure 1-3. E-type connector
Quick reference
Physical characteristics
21
6
5
1 Suture holes
2 P+/S port (5.0 mm)
3 HVA port (6.5 mm)
4 programmable Active Can
5 HVB port (6.5 mm)
6 P-/S port (5.0 mm)
2
3
4
1
Maximo VR 7232Cx, 7232B, 7232E Reference manual
22
Chapter 1
Magnet application
Magnet application
Bringing a magnet close to the device triggers changes in device
operation as shown in Table 1-5. When the magnet is removed,
the device returns to its programmed operations.
Tab le 1- 5. Effects of magnet application on the device
Pacing mode as programmed
Pacing rate and interval as programmed
VF, VT, and FVT detection suspended
a
b
Patient Alert audible
tones (20 seconds
or less)
with programmable alert(s) enabled:
■
continuous tone (Test)
■
on/off intermittent tone (seek
c
follow-up)
■
high/low dual tone (urgent follow-up)
with programmable alerts disabled:
■
no tone
■
high/low dual tone (urgent follow-up)
a
Rate response adjustments are suspended while a Patient Alert tone sounds.
b
Detection resumes if telemetry is established and the application software is
running, or it resumes after the application software has started.
c
The Test tone does not sound if “VF Detection/Therapy Off” is the only alert
enabled.
Maximo VR 7232Cx, 7232B, 7232E Reference manual
Longevity projections
Longevity estimates are based on accelerated battery discharge
data and device modeling with EGM pre-storage off, 60 ppm
-1
(min
) pacing rate, with
■
2.5 V pacing pulse amplitude, 0.4 ms pacing pulse width, and
35 J delivered therapy energy (see Table 1-6)
■
3 V pacing pulse amplitude, 0.4 ms pacing pulse width, and
35 J delivered therapy energy (see Table 1-7)
This model assumes default automatic capacitor formation
setting. As a guideline, each full energy charge decreases device
longevity by approximately 43 days.
Device longevity is affected by how certain features are
programmed, such as EGM pre-storage. For more information,
see “Optimizing device longevity” on page 193.
Considerations for using EGM pre-storage
When the EGM pre-storage feature is programmed off, the device
starts to store EGM following the third tachyarrhythmia event and
also provides up to 20 seconds of information before the onset of
the tachyarrhythmia, including:
■
VV intervals
■
Marker Channel
■
interval plot Flashback
Quick reference
Longevity projections
23
When the EGM pre-storage feature is programmed on, the device
also collects up to 20 seconds of EGM information before the
onset of the arrhythmia.
In a patient who uniformly repeats the same onset mechanisms,
the greatest clinical benefit of pre-onset EGM storage is achieved
after a few episodes are captured.To maximize the effectiveness
of the EGM pre-storage feature and optimize device longevity,
consider these programming options:
■
Turn pre-storage on to capture possible changes in the onset
mechanism following significant clinical adjustments, for
example, device implant, medication changes, and surgical
procedures.
■
Turn pre-storage off once you have successfully captured the
information of interest.
Maximo VR 7232Cx, 7232B, 7232E Reference manual
24
Chapter 1
Longevity projections
Tab le 1- 6. Projected longevity in years with 2.5 V pacing amplitude and
0.4 ms pulse width
Percent
pacing
Maximum
energy charging
frequency
a
EGM
pre-storage
500 ohm
b
impedance
pacing
900 ohm
pacing
impedance
0% Semi-Annual Off 10.1 10.1
On 9.8 9.8
Quarterly Off 8.3 8.3
On 8.1 8.1
15% Semi-Annual Off 9.8 10.0
On 9.6 9.7
Quarterly Off 8.1 8.2
On 7.9 8.0
50% Semi-Annual Off 9.3 9.7
On 9.1 9.5
Quarterly Off 7.8 8.0
On 7.6 7.8
100% Semi-Annual Off 8.7 9.3
On 8.5 9.1
Quarterly Off 7.3 7.7
On 7.1 7.6
a
Maximum energy charging frequency may include full energy therapy shocks or
capacitor formations.
b
The data provided for programming EGM pre-storage on is based on a 6 month
period (two 3-month follow-up intervals) over the life of the device. Additional
use of EGM pre-storage reduces longevity by approximately 27% or 3 months
per year.
Maximo VR 7232Cx, 7232B, 7232E Reference manual
Quick reference
Longevity projections
Tabl e 1-7 . Projected longevity in years with 3 V pacing amplitude and
0.4 ms pulse width
Percent
pacing
0% Semi-Annual Off 10.1 10.1
15% Semi-Annual Off 9.8 9.9
50% Semi-Annual Off 9.1 9.5
100% Semi-Annual Off 8.2 9.0
a
Maximum energy charging frequency may include full energy therapy shocks or
capacitor formations.
b
The data provided for programming EGM pre-storage on is based on a 6 month
period (two 3-month follow-up intervals) over the life of the device. Additional
use of EGM pre-storage reduces longevity by approximately 27% or 3 months
per year.
Maximum
energy charging
frequency
a
EGM
pre-storage
500 ohm
b
impedance
pacing
900 ohm
pacing
impedance
On 9.8 9.8
Quarterly Off 8.3 8.3
On 8.1 8.1
On 9.5 9.7
Quarterly Off 8.0 8.1
On 7.9 8.0
On 8.8 9.3
Quarterly Off 7.6 7.9
On 7.4 7.7
On 8.0 8.8
Quarterly Off 7.0 7.5
On 6.8 7.3
25
Maximo VR 7232Cx, 7232B, 7232E Reference manual
26
Chapter 1
Replacement indicators
Replacement indicators
Battery voltage and messages about replacement status appear
on the programmer display and on printed reports. Table 1-8 lists
the Elective Replacement Indicator (ERI) and the End of Life
(EOL) conditions.
Tab le 1- 8. Replacement indicators
Elective Replacement (ERI) ≤ 2.62 V
End of Life (EOL) 3 months after ERI
ERI date – The programmer displays the date when the battery
reached ERI on the Quick Look and Battery and Lead
Measurements screens.
Temporary voltage decrease – The battery voltage temporarily
decreases following a high-voltage charge. If a battery
measurement is taken immediately after a high-voltage charge,
the ERI or EOL indicator may be displayed. However, this is a
temporary status which will return to normal when the battery has
recovered from the charge.
EOL indication – If the programmer indicates that the device is at
EOL, replace the device immediately.
Post-ERI conditions – EOL device status is defined as three
months following an ERI indication assuming the following
post-ERI conditions: 100% VVI pacing at 60 ppm (min
0.4 ms; 500 Ω pacing load; and six 35 J charges. EOL may be
indicated before the end of three months if the device exceeds
these conditions.
Maximo VR 7232Cx, 7232B, 7232E Reference manual
-1
), 3 V,
Typical charge times
The most recent capacitor charge time appears on the
programmer display and on printed reports and can be evaluated
using the Charge/Dump test (see Table 1-9).
Tabl e 1-9 . Ty p ic ala full energy charge times
At Beginning of Life (BOL) 7.0 seconds
At Elective Replacement (ERI) 9.1 seconds
a
These charge times are typical when the capacitors are fully formed.
High-voltage therapy energy
The stored energy of the device is derived from the peak capacitor
voltage and is always greater than the energy delivered by the
device. Table 1-10 compares the programmed energy levels
delivered by the device to the energy levels stored in the
capacitors before delivery.
Quick reference
Typical charge times
27
Maximo VR 7232Cx, 7232B, 7232E Reference manual
28
Chapter 1
High-voltage therapy energy
Table 1-10. Comparing delivereda (programmed) and storedb energy levels
Energy (J) Charge
Delivered a/
Stored
b
Programmed
35 39 7.0 10 12 2.0
32 37 6.4 9 10.5 1.8
30 34 6.0 8 9.3 1.6
28 32 5.6 7 8.2 1.4
26 30 5.2 6 7.1 1.2
25 29 5.0 5 5.9 1.0
24 27 4.8 4 4.8 0.8
22 25 4.4 3 3.6 0.6
20 23 4.0 2 2.4 0.4
18 21 3.6 1.8 2.2 0.4
16 19 3.2 1.6 2.0 0.3
15 17 3.0 1.4 1.7 0.3
14 16 2.8 1.2 1.5 0.2
13 15 2.6 1.0 1.2 0.2
12 14 2.4 0.8 1.0 0.2
11 13 2.2 0.6 0.8 0.1
a
Energy delivered at connector block into a 75 ohm load.
b
Energy stored at end of charge on capacitor.
c
Typical charge time at Beginning of Life (BOL) with fully formed capacitors, rounded to the nearest tenth of
a second.
Time
c
(sec)
Delivered a/
Programmed
0.4 0.5 0.1
Energy (J) Charge
Timec (sec)
b
Stored
Maximo VR 7232Cx, 7232B, 7232E Reference manual
Stored data and diagnostics
Tabl e 1-1 1. Stored data and diagnostics
Episode data
Quick reference
Stored data and diagnostics
29
Tachy episodes 150 VF/VT/FVT episodes: intervals, text, EGM,
QRS Snapshot
EGM capacity for
tachy episodes
14 minutesb of dual-channel EGM, or
23.5 minutes
a
c
of single-channel EGM
SVT/NST episodes 50 SVT/NST episodes: intervals, text, EGM,
QRS Snapshota (the device does not usually
store detailed episode records for NST
episodes)
d
EGM capacity for
SVT/NST episodes
2 minutes
3.6 minutese of single-channel EGM
of dual-channel EGM, or
EGM sources Six options: ventricular / far-field
EGM options Store before onset; Store during charging
Flashback memory 2000 intervals (V-V): before latest VF, before
latest VT, and before interrogation
Counter data
Detection counters Lifetime total, since cleared, and since last
session
Episode counters Episodes:
■
VF, FVT, and VT
■
NST episodes and SVTs
Percentage pacing:
■
VS and VP percentages
Additional counters:
■
Single PVCs and PVC runs
■
Rate stabilization pulses and runs
Therapy efficacy
counters
Counts for each VF, FVT, VT Therapy:
■
Delivered
■
Successful
■
Unsuccessful
■
Intervention (manually aborted)
Total number of aborted shocks
Maximo VR 7232Cx, 7232B, 7232E Reference manual
30
Chapter 1
Stored data and diagnostics
Tab le 1- 11. Stored data and diagnostics (continued)
Other stored data
Patient Alert events Up to 10 log entries: text and date for the first
time an alert is triggered between interrogations
Battery and lead
measurements
Battery voltage, last capacitor formation, last
charge, lead impedance, EGM amplitude
measurements, last high-voltage therapy, and
sensing integrity counter
Lead performance
trends
14 days of daily measurements plus 80 weeks
of weekly minimum and maximum
measurements:
■
Lead impedance: ventricular pacing,
defibrillation pathway, and SVC lead
(if used)
■
Ventricular EGM amplitude (R-waves)
Cardiac Compass
trends
14 months of measurement trends:
■
VT and VF episodes per day
■
High-voltage therapies delivered per day
■
Ventricular rate during VT or VF
■
Episodes of non-sustained tachycardia
per day
■
Heart rate variability
■
Percent of time pacing is active
■
Patient activity
■
Average day and night ventricular
heart rate
a
When Wavelet is set to On or Monitor
b
13.5 minutes if Wavelet is set to On or Monitor
c
22 minutes if Wavelet is set to On or Monitor
d
1.6 minutes if Wavelet is set to On or Monitor.
e
2.75 minutes if Wavelet is set to On or Monitor.
Maximo VR 7232Cx, 7232B, 7232E Reference manual
Loading...