Transcript Subcutaneous Implantable Cardioverter Defibrillator (S-ICD)

Subcutaneous Implantable
Cardioverter Defibrillator (S-ICD)
Tanner Barnes
BME 281
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)
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
Problems with T-ICD:
• Infections in the venous system
• 2,201 patients required lead
removals between 2000-2011
• Complex and highly invasive
operation
• T-ICD’s often unsuccessful in
children
• Requires x-ray imaging to ensure
the lead is placed correctly
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
Design of S-ICD:
The S-ICD System is comprised of the following four
devices:
1.SQ-RX Pulse Generator
– 80-J biphasic shock
– Charge time to 80-J ≤ 10 seconds
– 5.1 year longevity
– 30 seconds post-shock pacing
2.Q-TRAK Subcutaneous Electrode
3.Q-GUIDE Electrode Insertion Tool (EIT)
4.Q-TECH Programmer
Implantation of S-ICD:
• All components implanted just below the skin
• Only requires 3 small incisions
• Can be an outpatient procedure
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
Disadvantages:
• Size
– 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
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
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 80J shocks
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
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
References
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McLeod, Dr. Karen, and Dr. Andrew McLean. "Implantation of a Fully Subcutaneous ICD in Children."
Authors. Journal compilation. 35. (2012): 20-23. Web. 19 Oct 2013.
Hauser, Dr.Robert. "The Subcutaneous Implantable Cardioverter-Defibrillator." Journal of the American
College of Cardiology. 61.1 (2013): 20-22. Web. 19 Oct 2013.
"Safety and Efficacy of a Totally Subcutaneous Implantable-Cardioverter Defibrillator." Circulation. 128.
(2013): 944-953. Web. 20 Oct. 2013.
"Superior Vena Cava Defibrillator Coils Make Transvenous Lead Extraction More Challenging and Riskier."
Journal of the American College of Cardiology. 61.9 (2013): 987-989. Web. 20 Oct. 2013.
Boston Scientific. Boston Scientific. Web. 20 Oct 2013. <http://www.bostonscientific.com/cardiac-rhythmresources/cameron-health/sicd-system.html>.
"What Causes Sudden Cardiac Arrest?." National Heart, Lung, and Blood Institute. N.p., 1 1 2011. Web. 20
Oct 2013. <http://www.nhlbi.nih.gov/health/health-topics/topics/scda/causes.html>.
"Subcutaneous Implantable Defibrillator (S-ICD) System Advisory Panel Package Summary of Safety and
Effectiveness Data." . FDA. Web. 20 Oct 2013.
<http://www.fda.gov/downloads/AdvisoryCommittees/CommitteesMeetingMaterials/MedicalDevices/Me
dicalDevicesAdvisoryCommittee/CirculatorySystemDevicesPanel/UCM301237.pdf>.
<http://www.epdoc.net/professional/patientpages/Equipment-and-Device-Images.aspx>
Boston Scientific. “Fundamentals of ICD Therapy”.
<http://www.columbia.edu/itc/hs/medical/hickey/docs/Evolution%20of%20ICD%20Therapy%20010907.p
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