Biotronik BELOS-T User Manual
(Draft)
Cardiac Airbag /
Cardiac Airbag-T
Family of Implantable Cardioverter
Defibrillators and Software Cartridge for
TMS 1000
PLUS
and EPR 1000
PLUS
Technical Manual
X-ray Identification
Cardiac Airbag/Cardiac Airbag-T
Implantable Cardioverter Defibrillator
Inside the housing, top left-hand side:
Year of manufacture
X-Ray identification
EI•
CAUTION
Federal (U.S.A.) law restricts this device to sale by, or on the
order of, a physician.
2003 BIOTRONIK, Inc., all rights reserved.
Cardiac Airbag Technical Manual i
Contents
1. General...........................................................................1
1.1 System Description....................................................1
1.2 Indications and Usage ...............................................2
1.3 Contraindications .......................................................2
1.4 Warnings and Precautions.........................................3
1.4.1 Sterilization, Storage, and Handling ..................3
1.4.2 Device Implantation and Programming..............4
1.4.3 Lead Evaluation and Connection.......................6
1.4.4 Follow-up Testing...............................................7
1.4.5 Pulse Generator Explant and Disposal..............8
1.4.6 Hospital and Medical Hazards ...........................9
1.4.7 Home and Occupational Hazards......................11
1.4.8 Cellular Phones..................................................11
1.4.9 Electronic Article Surveillance (EAS).................12
1.4.10 Home Appliances ...............................................12
1.5 Adverse Events..........................................................13
1.5.1 Potential Adverse Events...................................13
1.5.2 Observed Adverse Events .................................14
1.6 Clinical Studies ..........................................................17
1.6.1 Patients Studied.................................................17
1.6.2 Methods .............................................................18
1.6.3 Results ...............................................................18
1.7 Patient Selection and Treatment ...............................20
1.7.1 Individualization of Treatment............................20
1.7.2 Specific Patient Populations ..............................20
1.8 Patient Counseling Information .................................20
1.9 Evaluating Prospective ICD Patients.........................21
2. Device Features ............................................................22
2.1 Sensing ......................................................................22
2.1.1 Ventricular Sensitivity Settings ..........................22
2.1.2 Minimum Ventricular Threshold .........................25
2.2 Ventricular Tachyarrhythmia Detection ......................25
2.2.1 VF Classifications ..............................................26
2.2.2 VT Interval Counters ..........................................26
2.2.3 VT Classification ................................................26
2.2.4 Onset and Stability.............................................27
ii Cardiac Airbag Technical Manual
2.3 Tachyarrhythmia Redetection ....................................28
2.3.1 VT Redetection ..................................................28
2.3.2 VF Redetection ..................................................28
2.3.3 Tachyarrhythmia Termination ............................28
2.4 Tachyarrhythmia Therapy ..........................................28
2.4.1 Shock Therapy...................................................29
2.5 Bradycardia Therapy .................................................31
2.5.1 Bradycardia Pacing Modes................................31
2.5.2 Basic Rate..........................................................31
2.5.3 Rate Adaptation .................................................31
2.5.4 Gain and Threshold ...........................................32
2.5.5 Rate Increase / Decrease ..................................32
2.5.6 Maximum Sensor Rate ......................................32
2.5.7 Pulse Amplitude .................................................32
2.5.8 Pulse Width........................................................33
2.5.9 Noise Response.................................................33
2.5.10 Post Shock Pacing.............................................33
2.6 Special Features........................................................33
2.6.1 Home Monitoring (Cardiac Airbag-T Only) ........33
2.6.2 Real-time IEGM Transmission...........................37
2.6.3 Capacitor Reformation .......................................37
2.6.4 Patient and Implant Data ...................................38
2.6.5 System Status....................................................39
2.6.6 Holter Memory ...................................................40
2.6.7 Arrhythmia Induction Features...........................42
2.6.8 Manual Shock ....................................................43
2.6.9 Test Shock .........................................................43
3. Software Features.........................................................44
3.1 Follow-Up Assistant (FAST) Window.........................44
3.1.1 Interrogate ICD without Follow-up .....................45
3.2 Main Function Keys ...................................................45
3.3 Parameter Window ....................................................47
4. Sterilization and Storage..............................................50
5. Implant Procedure ........................................................52
5.1 Implant Preparation ...................................................52
5.2 Lead System Evaluation ............................................52
5.3 Opening the Sterile Container ...................................53
5.4 Pocket Preparation ....................................................53
5.5 Lead to Device Connection .......................................54
Cardiac Airbag Technical Manual iii
5.6 Blind Plug Connection ...............................................55
5.7 Program the ICD........................................................56
5.8 Implant the ICD..........................................................56
5.9 Suggested Cardiac Airbag Implant Procedure ..........57
6. Follow-up Procedures ..................................................68
6.1 General Considerations.............................................68
6.2 Suggested Cardiac Airbag Follow-Up Procedure......68
6.3 Longevity....................................................................74
6.3.1 Standard ERI Method ........................................74
6.3.2 Treated VF Episode ERI Method.......................76
6.4 Explantation ...............................................................78
7. Technical Specifications ..............................................80
Appendix A...........................................................................85
iv Cardiac Airbag Technical Manual
Cardiac Airbag Specifications
Battery Voltage: 6.3 Volts
Maximum Shock Energy: 30 joules
Defibrillation Lead Ports Two DF-1 (3.2 mm)
Pacing Lead Ports One IS-1 (3.2 mm)
Dimension: 55 x 67 x 13 mm
Volume: 39 cc
Mass: 73 g
Housing Material: Titanium
Header Material: Epoxy Resin
Sealing Plug Material: Silicone
Battery Composition Li / MnO2
Cardiac Airbag Technical Manual 1
1. General
1.1 System Description
The Cardiac Airbag family of Implantable Cardioverter
Defibrillators (ICDs) detects and treats ventricular
tachyarrhythmias as well as provides rate adaptive bradycardia
pacing support. The ICDs are designed to collect diagnostic data
to aid the physician’s assessment of a patient’s condition and the
performance of the implanted device. The Cardiac Airbag ICDs
are specifically designed to have reduced complexity for implant
and follow-up, yet provide essential therapies for conversion of
life threatening ventricular tachyarrhythmias.
There are 10 programmable parameters to simplify the implant
procedure, and detailed diagnostic information is stored for up to
10 ventricular tachycardia (VT) episodes and 3 treated
ventricular fibrillation (VF) episodes. There are 30 minutes of
single-channel IEGM storage available to record spontaneous
and induced ventricular tachyarrhythmias. The Cardiac Airbag is
restricted to storage of diagnostic information up to and including
3 treated ventricular fibrillation episodes.
The Cardiac Airbag ICDs provide therapy for ventricular
tachyarrhythmias with programmable defibrillation therapy. The
ICDs provide high energy biphasic shocks with the first shock
having with programmable energies of 20 or 30 joules and up to
8 shocks per VF episode. The remaining 7 shocks in the
therapy progression are pre-set at 30 joules.
The Cardiac Airbag family of ICDs includes the following
members:
• Cardiac Airbag provides therapies for ventricular
tachyarrhythmias and single chamber rate adaptive
bradycardia pacing support.
• Cardiac Airbag-T is identical to the Cardiac Airbag with
the added functionality of BIOTRONIK’s Home
Monitoring system. The Home Monitoring System
enables automatic exchange of information about a
patient’s cardiac status from the implant to the physician
remotely.
2 Cardiac Airbag Technical Manual
The Cardiac Airbag and Cardiac Airbag-T have two DF-1
defibrillation / cardioversion and one IS-1 pacing/sensing header
ports. IS-1 refers to the international standard whereby leads
and generators from different manufacturers are assured a basic
fit [Reference ISO 5841-3:1992]. DF-1 refers to the international
standard for defibrillation lead connectors [Reference ISO
11318:1993].
External devices that interact with and test the implantable
devices are also part of the ICD System. These external devices
include the TMS 1000
and the EPR 1000
These programmers are used to interrogate and program the
ICDs. In addition, the programmer software is used to perform
the interrogation and programming of the ICDs during implant
and follow-up testing.
PLUS
PLUS
Tachyarrhythmia Monitoring System
Programming and Monitoring System.
1.2 Indications and Usage
The Cardiac Airbag Implantable Cardioverter Defibrillators
(ICDs) are intended to provide ventricular defibrillation for
automated treatment of life-threatening ventricular arrhythmias.
1.3 Contraindications
Do not use the Cardiac Airbag Implantable Cardioverter
Defibrillators (ICDs) in patients:
• Whose ventricular tachyarrhythmias may have transient
or reversible causes including:
- acute myocardial infarction
- digitalis intoxication
- drowning
- electrocution
- electrolyte imbalance
- sepsis
- hypoxia
• Patients with incessant VT of VF
• Patients with unipolar pacemaker
• Patients whose only disorder is brady arrhythmia or
atrial arrhythmia
Cardiac Airbag Technical Manual 3
1.4 Warnings and Precautions
ATP (Anti-Tachycardia Pacing) – The Cardiac Airbag ICD
does not provide ATP therapy. Do not implant this ICD in
patients with documented ventricular tachycardias unless high
energy defibrillation is desired for treatment of the ventricular
arrhythmia.
MRI (Magne
to MRI device scanning. Strong magnetic fields may damage
the device and cause injury to the patient.
tic Resonance Imaging) - Do not expose a patient
Electrical Isolation - To prevent ina
induction, electrically isolate the patient during the implant
procedure from potentially hazardous leakage currents.
Lead Systems - The use of another manufacturer’s I
system may cause potential adverse consequences such as
under sensing of cardiac activity and failure to deliver necessary
therapy.
Resuscit
unless an alternate source of patient defibrillation such as an
external defibrillator is readily available. In order to implant the
ICD system, it is necessary to induce and convert the patient’s
ventricular tachyarrhythmias.
Unwanted Shocks – Always
Therapy status to DISABLED prior to handling the device to
prevent the delivery of serious shocks to the patient or the
person handling the device during the implant procedure.
Rate-Adaptive Pacing – Use rate-adaptive pacing with care
patients unable to tolerate increased pacing rates.
ation Availability - Do not perform induction testing
program the VT/VF Detection and
dvertent arrhythmia
CD lead
in
1.4.1 Sterilization, Storage, and Handling
Device Packaging - Do not use the device if the
packaging is wet, punctured, opened or damaged because the
integrity of the sterile packaging may be compromised. Return
the device to BIOTRONIK.
device’s
Re-sterilization - Do not r
devices.
e-sterilize and re-implant explanted
4 Cardiac Airbag Technical Manual
Storage (temperature) - Store the device between 5° to 55°C
(41° - 131° F) because temperatures outside this range could
damage the device.
Storage (magnets) - To avoid damage to the device, store the
device in a clean area, away from magnets, kits containing
magnets, and sources of electromagnetic interference (EMI).
Temperature Stabilization - Allow the device to reach room
temperature before programming or implanting the device
because temperature extremes may affect initial device function.
Use Before Date - Do not implant the device after the USE
BEFORE DATE because the device may have reduced
longevity.
1.4.2 Device Implantation and Programming
Blind Plug - A blind plug must be inserted and firmly conn
into any unused header port to prevent chronic fluid influx and
possible shunting of high energy therapy.
Capacitor Reformation - Infrequent charg
capacitors may extend the charge times of the ICD. The
capacitors may be reformed manually, or the ICD may be
programmed to reform the capacitors automatically. For further
information, please refer to Section 2.6.3
Connector Compatibility - ICD and lead system compatibility
should be confirmed prior to the implant procedure. Consult
your BIOTRONIK representative regarding lead/pulse generator
compatibility prior to the implantation of an ICD system. For
further information, please refer to Appendix A
ERI (Elective Replacement Indicator) - Upon reaching ERI, the
battery has sufficient energy remaining to continue monitoring for
at least three months and to deliver a minimum of six 30 joule
shocks. After this period, tachyarrhythmia detection and therapy
will proceed until EOS is declared. Bradycardia functions are
still active at programmed values until the battery voltage drops
below 3.0 volts.
ing of the high voltage
, Capacitor Reforming.
.
ected
Cardiac Airbag Technical Manual 5
Magnets - Positioning of a magnet or the programming wand
over the ICD will suspend tachycardia detection and treatment.
The minimum magnet strength required to suspend tachycardia
treatment is 1.8 mT. When the magnet strength decreases to
less than 1 mT, the reed contact is reopened.
Pacemaker/ICD Interaction - In situations where an ICD and a
pacemaker are implanted in the same patient, interaction testing
should be completed. If the interaction between the ICD and the
pacemaker cannot be resolved through repositioning of the
leads or reprogramming of either the pacemaker or the ICD, the
pacemaker should not be implanted (or explanted if previously
implanted).
Programmed Parameters – Program the device parameters to
appropriate values based on the patient’s specific arrhythmias
and condition.
Programmers - Use only BIOTRONIK programmers to
communicate with the device (TMS 1000
EPR 1000
Sealing Sy m
PLUS
).
ste - Failure to properly insert the torque wrench
PLUS
, or
into the perforation at an angle perpendicular to the connector
receptacle may result in damage to the sealing system and its
self-sealing properties.
Defibrillation Thresho
ld - Be aware that the changes in the
patient’s condition, drug regimen, and other factors may change
the defibrillation threshold (DFT) which may result in nonconversion of the arrhythmia post-operatively. Successful
conversion of ventricular fibrillation or ventricular tachycardia
during arrhythmia conversion testing is no assurance that
conversion will occur post-operatively.
Manual Shocks – User-commanded s
hocks may be withheld if
the ICD is already busy processing a manual command or the
Battery Status is low.
Charge Time - When
preparing a high energy shock the charge
circuit stops charging the capacitors after 16 seconds, and
delivers the stored energy as shock therapy. After the device
reaches ERI the stored energy may be less than 30 joules per
shock.
6 Cardiac Airbag Technical Manual
Shock Impedance - If the shock impedance is less than twenty-
five ohms, reposition the lead system to allow a greater distance
between the electrodes. Never implant the device with a lead
system that has measured shock impedance as less than
twenty-five ohms. Damage to the device may result.
Programming Wand - Throughout the EP Test session, the
programming wand must be positioned and remain directly over
the device. If appropriate arrhythmia detection does not occur
shortly after induction, remove the programming wand from the
ICD and perform external defibrillation.
Data Transmission - Data collection and transmission may take
up to 30 seconds. The ICD cannot be reprogrammed during this
time even if the [Emergency] key is pressed. Remove the
programming wand immediately to restore the permanent
program.
EP Test Functions - Ensure that cardiac resuscitation
equipment is available during all EP Test Function operations.
Physicians should be trained and experienced in
tachyarrhythmia induction, conversion protocols, and have
adequate training and experience with this device prior to use.
Potential side effects include:
• Non-terminable arrhythmia’s that result in death
• Complications from hypoxia due to prolonged
arrhythmia’s
• Arrhythmia induction that requires cardioversion or
defibrillation
• Arrhythmia induction that requires pharmacologic
treatment, to which the patient could have an adverse
reaction
1.4.3 Lead Evaluation and Connection
Capping Leads - If a lead is abandoned rather than removed, it
must be capped to ensure that it is not a pathway for currents to
or from the heart.
Gripping Leads - Do not grip the lead with surgical instruments
or use excessive force or surgical instruments to insert a stylet
into a lead.
Cardiac Airbag Technical Manual 7
Kinking Leads - Do not kink leads. This may cause additional
stress on the leads that can result in damage to the lead.
Liquid Immersion - Do not immerse leads in mineral oil, silicone
oil, or any other liquid.
Short Circuit - Ensure that none of the lead electrodes are in
contact (a short circuit) during delivery of shock therapy as this
may cause current to bypass the heart or cause damage to the
ICD system.
Suturing Leads - Do not suture directly over the lead body as
this may cause structural damage. Use the appropriate suture
sleeve to immobilize the lead and protect it against damage from
ligatures.
Tricuspid Valve Bioprosthesis - Use ventricular transvenous
leads with caution in patients with a tricuspid valvular
bioprosthesis.
Setscrew Adjustment – Back-off the setscrew(s) prior to
insertion of lead connector(s) as failure to do so may result in
damage to the lead(s), and/or difficulty connecting lead(s).
Cross Threading Setscrew(s) – To prevent cross threading the
setscrew(s), do not back the setscrew(s) completely out of the
threaded hole. Leave the torque wrench in the slot of the
setscrew(s) while the lead is inserted.
Tightening Setscrew(s) – Do not overtighten the setscrew(s).
Use only the BIOTRONIK supplied torque wrench.
Sealing System – Be sure to properly insert the torque wrench
into the perforation at an angle perpendicular to the connector
receptacle. Failure to do so may result in damage to the plug
and its self-sealing properties.
1.4.4 Follow-up Testing
Defibrillation Threshold - Be aware that changes in the
patient’s condition, drug regimen, and other factors may change
the defibrillation threshold (DFT), which may result in nonconversion of the arrhythmia post-operatively. Successful
conversion of ventricular fibrillation or ventricular tachycardia
during arrhythmia conversion testing is no assurance that
conversion will occur post-operatively.
8 Cardiac Airbag Technical Manual
Resuscitation Availability - Ensure that an external defibrillator
and medical personnel skilled in cardiopulmonary resuscitation
(CPR) are present during post-implant device testing should the
patient require external rescue.
Safe Program – Within the EP Test screen, pressing the “Safe
Program” key on the programmer head does not immediately
send the safe program to the ICD. Pressing the “Safe Program”
key activates the emergency function
screen touch is required to send the safe program to the ICD.
Date and Time Values - If date and time values are incorrect,
the system may, as a result, generate false system status
information for the implant.
Impedance Measurement - During the impedance
measurement with high stimulation amplitudes, nerve or skeletal
muscles may be briefly stimulated.
Threshold Test - A minimum 2:1 voltage safety margin should
be permanently programmed any time capture thresholds a
assessed. Monitor the ECG display closely with pacerdependent patients. The test should be terminated immediately
upon loss of capture.
screen, but an additional
re
Inadvertent Programming - The programmer utilizes a touch
sensitive screen for menu selections. Care must be used to
avoid inadvertent menu selection
screen.
by accidentally touching the
1.4.5 Pulse Generator Explant and Disposal
Device Incineration – Never incinerate the ICD due to the
potential for explosio
cremation.
Explanted Devices – Return all explanted devices to
BIOTRONIK.
Unwante
DISABLED prior to handling the device to prevent the deliv
serious shocks to the patient or the person handling the
during the implant procedure.
d Shocks – Always program the therapy status to
n. The ICD must be explanted prior to
ery of
device
Cardiac Airbag Technical Manual 9
1.4.6 Hospital and Medical Hazards
Electromagnetic interference (EMI) signals present in hospital
and medical environments may affect the function of any ICD or
pacemaker. The ICD is designed to selectively filter out EMI
noise. However, due to the variety of EMI signals, absolute
protection from EMI is not poss
The ICD system should have detection and
prior to performing any of the following medica
addition, the ICD should be checked after the procedures to
assure proper programming:
Diathermy - Diathermy therapy is not recommended for ICD
patients due to possible heating effects of the pulse generator
and at the implant site. If diathermy therapy must be used,
should not be applied in the immediate vicinity of the pulse
generator or lead system.
Electrocautery - Electrosurgical cautery could induce ventricular
arrhythmias and/or fibrillation,
or damage. If use of electrocautery is necessary, the current
path and ground plate should be kept as far away from the pulse
generator and leads as possible (at least 6 inches (15 cm)).
ible with this or any other ICD.
therapy disabled
l procedures. In
it
or may cause device malfunction
10 Cardiac Airbag Technical Manual
External Defibrillation - The device is protected against energy
normally encountered from external defibrillation. However, any
implanted device may be damaged by external defibrillation
procedures. In addition, external defibrillation may also result in
permanent myocardial damage at the electrode-tissue interface as
well as temporary or permanent elevated pacing thresholds. When
possible, observe the following precautions:
• Position the adhesive electrodes or defibrillation paddles
of the external defibrillator anterior-posterior or along a
line perpendicular to the axis formed by the implanted
device and the heart.
• Set the energy to a level not higher than is required to
achieve defibrillation.
• Place the paddles as far as possible away from the
implanted device and lead system.
• After delivery of an external defibrillation shock,
interrogate the ICD to confirm device status and proper
function.
Lithotripsy - Lithotripsy may damage the ICD. If lithotripsy must
be used, avoid focusing near the ICD implant site.
MRI (Magnetic Resonance Imaging) - Do not expose a patient
to MRI device scanning. Strong magnetic fields may damage
the device and cause injury to the patient.
Radiation - High radiation sources such as cobalt 60 or gamma
radiation should not be directed at the pulse generator. If a
patient requires radiation therapy in the vicinity of the pulse
generator, place lead shielding over the device to prevent
radiation damage and confirm its function after treatment.
Radio Frequency Ablation - Prior to performing an ablation
procedure, deactivate the ICD during the procedure. Avoid
applying ablation energy near the implanted lead system
whenever possible.
Cardiac Airbag Technical Manual 11
1.4.7 Home and Occupational Hazards
Patients should be directed to avoid devices that generate strong
electromagnetic interference (EMI) or magnetic fields. EMI could
cause device malfunction or damage resulting in non-detection
or delivery of unneeded therapy. Moving away from the source
or turning it off will usually allow the ICD to return to its normal
mode of operation.
The following equipment (and similar devices) may affect normal
ICD operation: electric arc or resistance welders, electric melting
furnaces , r a d i o / t e l e v i s i o n and radar t r a n s m i t t e r s ,
power-generating facilities, high-voltage transmission lines, and
electrical ignition systems (of gasoline-powered devices) if
protective hoods, shrouds, etc., are removed.
1.4.8 Cellular Phones
Testing has indicated there may be a potential interaction
between cellular phones and BIOTRONIK ICD systems.
Potential effects may be due to either the cellular phone signal or
the magnet within the telephone and may include inhibition of
therapy when the telephone is within 6 inches (15 centimeters)
of the ICD, when the ICD is programmed to standard sensitivity.
Patients having an implanted BIOTRONIK ICD who operate a
cellular telephone should:
• Maintain a minimum separation of 6 inches
(15 centimeters) between a hand-held personal cellular
telephone and the implanted device.
• Set the telephone to the lowest available power setting,
if possible.
• Patients should hold the phone to the ear opposite the
side of the implanted device. Patients should not carry
the telephone in a breast pocket or on a belt over or
within 6 inches (15 centimeters) of the implanted device
as some telephones emit signals when they are turned
ON, but not in use (i.e., in the listen or stand-by mode).
Store the telephone in a location opposite the side of
implant.
12 Cardiac Airbag Technical Manual
Based on results to date, adverse effects resulting from
interactions between cellular telephones and implanted ICDs
have been transitory. The potential adverse effects could
include inhibition or delivery of additional therapies. If
electromagnetic interference (EMI) emitting from a telephone
does adversely affect an implanted ICD, moving the telephone
away from the immediate vicinity of the ICD should restore
normal operation. A recommendation to address every specific
interaction of EMI with implanted ICDs is not possible due to the
disparate nature of EMI.
1.4.9 Electronic Article Surveillance (EAS)
Equipment such as retail theft prevention systems may interact
with pulse generators. Patients should be advised to walk
directly through and not to remain near an EAS system longer
than necessary.
1.4.10 Home Appliances
Home appliances normally do not affect ICD operation if the
appliances are in proper working condition and correctly
grounded and shielded. There have been reports of the
interaction of electric tools or other external devices (e.g. electric
drills, older models of microwave ovens, electric razors, etc.)
with ICDs when they are placed in close proximity to the device.
Cardiac Airbag Technical Manual 13
1.5 Adverse Events
1.5.1 Potential Adverse Events
The following is a list of the potential risks that may occur with
this device:
• Acceleration of arrhythmias
• Air embolism
• Bleeding
• Chronic nerve damage
• Erosion
• Excessive fibrotic tissue growth
• Extrusion
• Fluid accumulation
• Formation of hematomas or cysts
• Inappropriate shocks
• Infection
• Keloid formation
• Lead abrasion and discontinuity
• Lead migration / dislodgment
• Myocardial damage
• Pneumothorax
• Shunting current or insulating myocardium during
defibrillation with internal or external paddles
• Potential mortality due to inability to defibrillate or pace
• Thromboemboli
• Venous occlusion
• Venous or cardiac perforation
14 Cardiac Airbag Technical Manual
Patients susceptible to frequent shocks despite antiarrhythmic
medical management may develop psychological intolerance to
an ICD system that may include the following:
• Dependency
• Depression
• Fear of premature battery depletion
• Fear of shocking while conscious
• Fear that shocking capability may be lost
• Imagined shocking (phantom shock)
There may be other risks associated with this device that are
currently unforeseeable.
1.5.2 Observed Adverse Events
A clinical study of the Phylax XM involved 155 devices implanted
in 154 patients with cumulative implant duration of 1286 months
(mean implant duration 8.3 months). This clinical study was
performed with the Phylax XM and Phylax 06 ICDs, which are
earlier versions of the Cardiac Airbag ICDs. The observed
adverse events are applicable because the Cardiac Airbag ICD
is a downsized version of the Phylax XM with rate adaptive
pacing capabilities.
NOTE:
The Phylax XM ICD is an earlier generation of BIOTRONIK
devices. The Cardiac Airbag family is based upon the
Phylax XM and other BIOTRONIK ICDs (i.e., Belos VR and
Belos VR-T).
There were a total of five deaths during the course of the trial;
none of the deaths were judged by the clinical study investigator
to be device related. Heart failure was a major factor in two
deaths. The other three deaths were related to renal failure,
lung disease, and septic shock secondary to an ischemic bowel,
respectively. All five of the deaths occurred more than one
month post implant.
Cardiac Airbag Technical Manual 15
Two ICDs were explanted during the trial. One was secondary
to the patient being unable to tolerate further testing required by
the clinical protocol. The other was secondary to a systemic
infection; the patient was subsequently implanted with another
device.
Table 1 provides a summary of the adverse events that were
reported during the clinical study regardless of whether or not
the event was related to the ICD system. A complication is
defined as a clinical event that results in invasive intervention,
injury, or death. An observation is defined as a clinical event
that does not result in invasive intervention, injury, or death.
Table 1: Reported Adverse Events (AEs)
Number of Patients = 154, Number of Patient-Years = 107.1
Event # of pts
with
AEs
Complications (total) 7 8 0.07 4.5%
% of
pts
with
AEs
# of
AEs
AE/
pt-
yrs
Lead repositioning 2 1.3% 2 0.02
Hematoma 1 0.6% 1 0.01
Systemic infection 1 0.6% 1 0.01
Explant (did not to tolerate
1 0.6% 1 0.01
testing)
Insertion of separate sensing 1 0.6% 2 0.02
lead
ICD/lead connection 1 0.6% 1 0.01
Observations (total) 79 51.3% 89 0.83
Inappropriate therapy (SVT) 18 11.7% 20 0.19
ICD response to magnet in
1
wand
Software messages and 11 7.1% 13 0.12
2
errors
13 8.4% 15 0.14
Increased pacing threshold 7 4.5% 9 0.08
Decreased R-wave
amplitude
Frequent VT 5 3.2% 5 0.05
7 4.5% 7 0.07
Oversensing 3 1.9% 3 0.03
TMS 1000 difficulties3 3 1.9% 3 0.03
VT below rate cut-off 2 1.3% 3 0.03
16 Cardiac Airbag Technical Manual
Event # of pts
with
AEs
High DFT’s 1 0.6% 2 0.02
% of
pts
with
AEs
# of
AEs
AE/
pt-
yrs
Minor stroke 1 0.6% 1 0.01
Renal failure 1 0.6% 1 0.01
Required additional drug
1 0.6% 1 0.01
therapy
ICD/lead connection 1 0.6% 1 0.01
ICD therapy during lead
1 0.6% 1 0.01
connection
Non-sustained VT 1 0.6% 1 0.01
Non-conversion of
arrhythmia
Interpretation of real-time 1 0.6% 1 0.01
1 0.6% 1 0.01
markers
Reconfirmation algorithm 1 0.6% 1 0.01
1. This category inclu
the
programmer wand that caused the reed switch to
toggle during hig age pacito ha ng or
des is s re o m em f
sue lated t ov ent o
h volt ca r c rgi
tachyarrhythmia detection. As a result, appropriate
therapy was not delivered in a timely manner. The
orientation of the reed switch was optimized and is being
monitored as part of the manufacturing process to
prevent future occurrences of this type of event.
2.
This category includes various software “anomalies” that
were related to error messages or the retrieval of
diagnostic information. Each of these events has been
resolved through revisions made to the software.
3. This category includes any difficulties encountered while
using the TMS 1000 Tachyarrhythmia Monitoring
System. Each of these events has been resolved
through revisions to the software and hardware
of the
system.
Cardiac Airbag Technical Manual 17
1.6 Clinical Studies
N
OTE:
The Phylax XM ICD is an earlier generation of BIOTRONIK
devices. The Cardiac Airbag family is based upon the
Phylax XM and other BIOTRONIK ICDs (i.e., Belos VR and
Belos VR-T).
This clinical study was performed on the Phylax XM and
Phylax 06 ICDs, which are earlier versions of the Cardiac
Airbag ICD. The clinical study data presented here is applicable
because the Cardiac Airbag / Cardiac Airbag-T is a downsized
version of the Phylax XM with the addition of rate adaptive
pacing capabilities. The Cardiac Airbag / Cardiac Airbag-T ICDs
are slightly different as compared to the Phylax XM in the
following areas:
• Motion based rate adaptive pacing
• Reduced programmable feature set
• Minor adjustments to therapy delivery options including
no availability of ATP
• Reduced size from 69 cc to 39 cc
• Addition of Home Monitoring functionality
The rate adaptive pacing circuitry of Cardiac Airbag / Cardiac
Airbag-T ICD is based on other US distributed BIOTRONIK
products. Due to the similarities between the Cardiac Airbag /
Cardiac Airbag-T, Belos VR / VR-T, and Phylax XM and the
limited nature of these changes, a clinical study of the
Cardiac Airbag / Cardiac Airbag-T ICD was determined to be
unnecessary.
1.6.1 Patients Studied
The clinical study involved 154 patients (121 male and 33
female) with a mean age of 64.9 years (range: 26 to 95 years)
and a left ventricular ejection fraction of 33% (range: 10% to
80%). Most (72%) presented with coronary artery disease /
ischemic cardiomyopathy; 71% presented with monomorphic
ventricular tachycardia (MVT) as their primary tachyarrhythmia.
18 Cardiac Airbag Technical Manual
1.6.2 Methods
The multicenter clinical investigation was designed to validate
the safety and effectiveness of the ICD system to detect and
treat monomorphic ventricular tachycardia (MVT), polymorphic
ventricular tachycardia (PVT), ventricular fibrillation (VF), and
bradycardia. The specific predefined objectives of the
investigation included the determination of ventricular
tachyarrhythmia conversion rate, sudden cardiac death (SCD)
survival rate, morbidity rate, and the appropriate sensing and
pacing rate.
The primary endpoint of the study was to evaluate the ventricular
tachyarrhythmia conversion rate. Patients underwent standard
ICD implantation and then were evaluated at predischarge and
regular follow-ups every three months. Induction and conversion
of the patient’s tachyarrhythmias was required at the implant
procedure and predischarge follow-up.
1.6.3 Results
The mean implant duration was 8.3 ± 0.4 months with
cumulative implant duration of 1286 months. There were 39
patients followed for over twelve months and 108 patients
followed for over six months. The patient follow-up compliance
rate was 99.6% out of 473 follow-up procedures.
2 provides a summary of the results of the study group for
Table
the predefined endpoints.
Cardiac Airbag Technical Manual 19
Table 2: Clinical Study Results
Description Study Group
[95% CI]
Tachyarrhythmia Conversion Rate
Induced
1
95.8% (496/518)
[93.6%, 97.3%]
Spontaneous 99.7% (1540/1544)
[99.3%, 99.9%]
Total 98.7% (2036/2062)
[98.2%, 99.2%]
Sudden Cardiac Death Survival
(at one year)
Complication Rate
(per total number of patients)
Appropriate Sensing and Pacing Rate
100.0% (39/39)
[91.0%, 100.0%]
5.2% (8/154)
[2.3%, 10.0%]
2
98.0% (703/717)
[96.8%, 98.9%]
1. Conversion data were collected in the clinical study for
both induced and spontaneous tachyarrhythmia
episodes. Therefore, both types of tachyarrhythmia
episodes were included in the analysis.
2. The investigator determined the appropriateness of
bradycardia sensing and pacing. The rate will be
determined by the number of appropriate bradycardia
sensing and pacing evaluations divided by the total
number of evaluations.
20 Cardiac Airbag Technical Manual
1.7 Patient Selection and Treatment
1.7.1 Individualization of Treatment
• Determine whether the expected device benefits
outweigh the possibility of early device replacement for
patients whose ventricular tachyarrhythmias require
frequent shocks.
• Determine if the device and programmable options are
appropriate for patients with drug-resistant
supraventricular tachyarrhythmias (SVTs), because
drug-resistant SVTs can initiate unwanted device
therapy.
• Direct any questions regarding individualization of
patient therapy to your BIOTRONIK representative or
BIOTRONIK technical services at 1-800-547-0394.
1.7.2 Specific Patient Populations
Pregnancy - If there is a need to image the device, care should
be taken to minimize radiation exposure to the fetus and the
mother.
Nursing Mothers - Although appropriate biocompatibility testing
has been conducted for this implant device, there has been no
quantitative assessment of the presence of leachables in breast
milk.
Geriatric Patients - Most (72%) of the patients receiving an ICD
in the Phylax XM clinical study were over the age of 60 years
(see Clinical Studies).
Handicapped and Disabled Patients - Special care is needed
in using this device for patients using electrical wheel chair or
other electrical (external or implanted devices).
1.8 Patient Counseling Information
The pulse generator is subject to random component failure.
Such failure could cause inappropriate shocks, induction of
arrhythmias or inability to sense arrhythmias, and could lead to
the patient’s death.
Cardiac Airbag Technical Manual 21
Persons administering CPR may experience the presence of
voltage on the patient’s body surface (tingling) when the patient’s
ICD system delivers a shock.
A patient manual is available for the patient, patient’s relatives,
and other interested people. Discuss the information in the
manual with concerned individuals both before and after pulse
generator implantation so they are fully familiar with operation of
the device. (For additional copies of the patient manual, contact
the BIOTRONIK at the address listed in this manual.)
1.9 Evaluating Prospective ICD Patients
The prospective ICD implant candidate should undergo a
cardiac evaluation to classify any and all tachyarrhythmias. In
addition, other patient specific cardiac information will help in
selecting the optimal device settings. This evaluation may
include, but is not limited to:
• an evaluation of the specific tachycardia rate(s)
• the confirmation and/or evaluation of any
supraventricular arrhythmias or bradyarrhythmias
• the evaluation of various ATP and cardioversion
therapies
• the presence of any post-shock arrhythmias, and
• an evaluation of the maximum sinus rate during exercise
If a patient’s drug regimen is changed or adjusted while the ICD
is implanted, additional EP testing may be required to determine
if detection or therapy parameter settings are relevant and
appropriate.
22 Cardiac Airbag Technical Manual
2. Device Features
The Cardiac Airbag family feature set is presented under the
following sub-headings: Sensing, Tachyarrhythmia Detection,
Tachyarrhythmia Redetection, Tachyarrhythmia Therapy,
Bradycardia Therapy, and Special Features. The features apply
to all members of the Cardiac Airbag family except where
specifically referenced differently.
2.1 Sensing
The Cardiac Airbag ICDs use Automatic Sensitivity Control
(ASC) to adjust the sensitivity characteristics to appropriately
detect the various cardiac signals. The characteristics of the
sensing circuitry have been optimized to ensure appropriate
sensing during all potential cardiac rhythms.
Cardiac signals vary in amplitude; therefore detection thresholds
cannot be static. The Automatic Sensitivity Control (ASC)
utilizes an automatic step-down threshold for sensing ventricular
signals. The ASC begins by tracking the cardiac signals (Rwaves) during the sensed refractory periods. The peak values
measured during this time are used to set the sensing thresholds
during the active detection periods.
2.1.1 Ventricular Sensitivity Settings
There are three programmable options for setting the sensitivity
of the input stage. The sensitivity selections are designed to
adapt the parameters of the input stage to various signal
conditions. The predefined parameter sets are described in
Table 3
.
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