1. Subcutaneous Implantable Cardioverter Defibrillator (S-ICD)
Tanner Barnes
BME 281

2. The Problem:
300,000 people die each year in the United States due to sudden cardiac arrest (SCA)
80-90% due to ventricular tachyarrhythmias
People who have severe coronary heart disease are at a heightened risk for (SCA)
Research shows that an implantable cardioverter-defibrillator (ICD) can reduce the chance of dying from (SCA)

3. A Solution: Transvenous implantable cardioverter-defibrillator (T-ICD)
First human implant in 1980
Gained FDA approval in 1985
First were “shock only”
Now able to provide pacing and have advanced rhythm discrimination

4. Problems with T-ICD: Infections in the venous system
2,201 patients required lead removals between
Complex and highly invasive operation
T-ICD’s often unsuccessful in children
Requires x-ray imaging to ensure the lead is placed correctly

5. A New Alternative:
Cameron Health, recently purchased by Boston Scientific, pioneered the subcutaneous implantable cardioverter-defibrillator (S-ICD) and it was put into commercial use outside the U.S. in 2009
The (S-ICD) was approved for observational study by FDA
Awaiting FDA approval for commercial use

6. Design of S-ICD:
The S-ICD System is comprised of the following four devices:
SQ-RX Pulse Generator
80-J biphasic shock
Charge time to 80-J ≤ 10 seconds
5.1 year longevity
30 seconds post-shock pacing
Q-TRAK Subcutaneous Electrode
Q-GUIDE Electrode Insertion Tool (EIT)
Q-TECH Programmer

7. Implantation of S-ICD:
All components implanted just below the skin
Only requires 3 small incisions
Can be an outpatient procedure

8. Advantages: Less invasive surgery
Eliminates potential for infection and damage to venous system
May be implanted using anatomical landmarks
Potential for less inappropriate shocks in children

9. Disadvantages: Size Battery life
Twice that of current T-ICD
Battery life
5 years as opposed to upwards of 10 with T-ICD
Does not provide anti-tachycardia pacing (ATP) or bradycardia pacing

10. S-ICD in Children: Study conducted in UK with two boys, aged 10 and 12
Early clinical trials suggest less inappropriate shocks than T-ICD
Can be implanted in children >30 kg
Possible for children <30 kg
Adapts to growth better than
T-ICD

11. Latest Observational Study:
330 patients in 33 different centers
99% complication free after 180 days
100% success rate in converting induced VT/VF to sinus rhythm
Only 1 out of 119 spontaneous VT/VF episodes required external defibrillation
Storm episode
37 out of 38 discrete spontaneous VT/VF episodes were corrected with one or more 80-J shocks

12. Continued:
The one episode terminated spontaneously while device was charging for second shock
Unintentional therapy occurred in 13.1% of patients over an 11-month follow-up
Similar to inappropriate therapy with T-ICD
The mean time to therapy for all inductions was 14.6 seconds

13. Conclusion:
The S-ICD system represents a viable alternative to conventional T-ICD therapy in patients at risk of death from VT/VF
Low rate of major complications thus far in European market and in clinical studies
FDA decision on approval should be announced in the near future

14. References
McLeod, Dr. Karen, and Dr. Andrew McLean. "Implantation of a Fully Subcutaneous ICD in Children." Authors. Journal compilation. 35. (2012): Web. 19 Oct 2013.
Hauser, Dr.Robert. "The Subcutaneous Implantable Cardioverter-Defibrillator." Journal of the American College of Cardiology (2013): Web. 19 Oct 2013.
"Safety and Efficacy of a Totally Subcutaneous Implantable-Cardioverter Defibrillator." Circulation (2013): Web. 20 Oct
"Superior Vena Cava Defibrillator Coils Make Transvenous Lead Extraction More Challenging and Riskier." Journal of the American College of Cardiology (2013): Web. 20 Oct
Boston Scientific. Boston Scientific. Web. 20 Oct <
"What Causes Sudden Cardiac Arrest?." National Heart, Lung, and Blood Institute. N.p., Web. 20 Oct <
"Subcutaneous Implantable Defibrillator (S-ICD) System Advisory Panel Package Summary of Safety and Effectiveness Data." . FDA. Web. 20 Oct <
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Boston Scientific. “Fundamentals of ICD Therapy”. <