This document summarizes the role of subcutaneous implantable cardioverter defibrillators (S-ICD) in preventing sudden cardiac death. It discusses: - How S-ICDs detect and treat ventricular fibrillation and tachycardia without leads in the heart. - Studies showing S-ICDs effectively detect and terminate arrhythmias while having a lower risk of complications than transvenous ICDs. - S-ICDs should be considered for any patient with an ICD indication who does not require cardiac pacing. Ongoing randomized trials will further establish the role of S-ICDs.

1. Rol actual del
cardiodesfibrilador
implantable subcutáneo en
la prevención de la muerte
súbita
Dr. Sergio L. Pinski
Cleveland Clinic Florida
Weston, Florida, USA
@SergioPinski

2. Moss AJ. Circulation 2005;111:2537

3. El CDI indicado en otros síndromes con alto
riesgo de muerte súbita
• Miocardiopatía hipertrófica
• QT largo
• Brugada
• Displasia arritmogénica del VD
• Miocardio no compactado
• Algunas distrofias musculares
• Sarcoidosis

9. Cost, complication & mortality rate were significantly
higher for infected vs non-infected devices
Trends in Complications Related to Infection Indication for TV Lead Extraction
Trends in Complications Related to Non-infection Indication for TV Lead Extraction
• The median costs of lead extraction was $39,308 for infected devices vs $14,916 for non-
infected leads.
• Lead extraction for infected device had a higher overall complication rate (9.2% vs 7.8%).
• In hospital mortality was 3.6% for those with infection versus 1.2% without infection.
*
*
*
*
* p=<0.001 for infected versus non-infected
Deschmuck et al. Circulation 2015;132:363

10. El pronóstico de pacientes con infecciones no
es muy bueno, aún luego de la extracción
Tarakji et al. Europace 2014;16:1490

11. Complicaciones a 6 meses: Registro danés
Kirkfeldt et al. Eur Heart J 2014;35:1186

12. Complicaciones y reoperaciones. Registro de
British Columbia
Hawkins et al. Heart 2018;104:237

13. The S-ICD Journey
IDE Trial2 321pts
EFFORTLESS3,4 985pts
PRAETORIAN Randomized Trial5 – enrolled 850pts
Post Approval Study8 - 1637pts
UNTOUCHED9 - enrolling 1100pts
43,000+ patients implanted WW12
4,000+ patients enrolled in completed
and on-going S-ICD clinical studies##
2008 2009 2010 2011 2012 2013 2014 2015 2016
Pooled
Analysis6
CE Mark study1 55pts
1st Generation
Inclusion in
ESC guidelines
(Class IIa)7
2nd Generation 3rd Generation
»
»
## Estimation from completed and ongoing clinical trials
2001- 2017+
Inclusion in
AHA/ACC/HRS
guidelines (Class
1 and IIa)10
S-ICD vs TV-ICD Meta-analysis 11 - >6400pts

14. Experiencia inicial con el CDI SC: Bardy,
Cameron Health
Bardy et al. N Engl J Med 2010;363:36

15. Características de la terapia del CDI subcutáneo
• Detección alrededor de 5 s
• Descarga bifásica
• 80J (entregados)
• Hasta 5 choques por episodio
• Tiempo de carga de 80J ≤ 10 s.
• Estimulación sólo post-choque (30 .)
• Almacenamiento de episodios (128 s) (44
episodios)
• Longevidad: 7.3 años*
* Uso normal, definido con reformas de condensadores cada 4 meses, cargas max. por episodios tratados/no tratados
retrasan la reforma

17. Nuestra técnica preferida: 2 incisiones submuscular
Migliore et al. PACE 2017;40:278

18. Escepticisimo
• Puede el desfibrilador SC detectar la fibrilación ventricular?
• Puede el desfibrilador SC desfibrilar consistentemente?
• Puede el desfibrilador SC discriminar entre arritmias ventriculares y
supraventriculares?

19. Valoración pre-operatoria basada en electrodos cutáneos posicionados a
lo largo de los vectores de sensado del sistema S-ICD
Screening pre-implante
• Valoración simple y rápida
• ECG registrados en dos
posturas: supina & sedestación
o bipedestación
• Electrocardiógrafo standard o
programador Boston
ALTERNATIVA
RA
LA
LL
DERIVADAI

20. ECG Screening
200 150 100 90 80 70 60 50 40 30
HEART RATE (25 mm/sec) 2 x RR FROM REFERENCE ARROW
200
400
600
800
1000
12000
8 cm GUIDE

21. INSIGHT™ Algorithm: Architecture
S-ECG signal similar
to a surface ECG
4 double-detection algorithms
designed to reduce over-
sensing
3 rhythm discriminators
to confirm therapy
PHASE I:
Detection
PHASE II:
Certification
PHASE III:
Therapy
Decision
Subcutaneous
signal detection
Heart rate
determined
HR assessed,
therapy confirmed

22. Bardy et al. N Engl J Med 2010;363:1

24. Prediction of an insufficient safety margin
for SQ defibrillation
Pacing
Higher Body Mass Index
White race
Lower LVEF
No previous CABG
Friedman et al. Circulation 2018;137:2463

25. Determinants of Subcutaneous ICD Efficacy
A Computer Modeling Study
Heist et al. JACC Clin EP 2017;3:405

26. Brouwer et al. JACC Clin EP 2016;2:89

27. The PRAETORIAN score
Quast et al. Heart Rhyhthm 2018 (in press)

28. @SergioPinski

29. @SergioPinski

30.  The SMART Pass feature activates an additional high-pass filter designed to reduce
cardiac over-sensing while still maintaining an appropriate sensing margin
 SMART Pass is only applied in the sensing path, while the morphology is unchanged
The SMART Pass filtering reduces the amplitude of lower frequency (slower moving) signals such as T-waves, by applying
an additional High Pass filter (lets higher frequencies “pass” through).
Higher Frequency (faster moving) signals such as R-waves, VT and VF amplitudes remain largely unchanged.
New sensing algorithm improves detection
Theuns et al. Heart Rhythn 2018;15:1515

31. Migliore et al. J Cardiovasc Med 2018;19;633

32. Migliore et al. J Cardiovasc Med 2018;19;633

33. Meta-análisis: Choques apropiados e inapropiados
Auricchio et al. Europace 2017;19:1973

34. Expected reduction in inappropriate shocks
from T wave oversensing
Theuns et al. Heart Rhythn 2018;15:1515

35. EFFORTLESS Registry Follow-Up, 985 pts
Boersma et al. JACC 2017;70;830

36. 1-year outcomes EFFORTLESS Registry
Boersma et al. JACC 2017;70;830

37. Meta-análisis de ICD SC vs TV
Basu-Ray et al. JACC Clin EP 2017;3:1475
Lead complications
Infection
System or device failure
Inappropriate shocks

38. SQ ICD in pts with previous TV-ICD infection
Boersma et al. Heart Rhythm 2016;13:157

39. Candidacy for SQ ICD based on surface ECG
template screening in pts with HCM
Maurizi et al. Heart Rhythm 2016;13;457

40. SQ ICD in Hypertrophic Cardiomyopathy
Lambiase et al. Heart Rhythm 2016;13;1066

42. ~76% of ICD patients in the U.S. have ≥1
comorbidity associated with high risk for
infection.2,4
76%
37% 39%
20%
23%
Heart Failure
(Class II-IV)
Diabetes Renal Disease (GFR<60) COPD Anticoagulant Use
% of ICD Patients in the U.S. with the following comorbidities4
Data on rates of comorbidities from Table 1 Friedman et al. JAMA Cardiology 2016

43. Algorithm for ICD selection
Al-Khatib et al. Circulation 2016;134:1390

44. NCDR Predictors Analysis Points to >80
Age as predictor of >5% RV Pacing
Effect Odds Ratio (95% CI) P value Overall P
value
PR interval & flutter
No AF/ PR interval <230 ms Reference
No AF/ PR interval≥230 ms 2.53 (0.83 - 7.69) 0.1028 <.0001
History of AF 3.337 (1.63 - 6.82) 0.0009 .
Ongoing AF at implant 11.717 (7.21 - 19.05) <.0001 .
Age
≤ 50 Reference
50-60 0.86 (0.38 - 1.93) 0.7101 0.0106
60-70 1.37 (0.67 - 2.82) 0.3936 .
70-80 1.96 (0.95 - 4.05) 0.0702 .
>80 3.29 (1.36 - 7.91) 0.008 .
Characteristics that were significantly associated with >5% right ventricular pacing
in the multivariate analysis in patients with a single chamber ICD.
Among patients with no pacing indication
at the time of ICD implant1:
• 1635 patients followed for 2 years
• Age >80 and history of AF related to the
development of pacing need after
implant
• Only 108 (6.6%) developed >5% RVP for
any 90 day period
• “The development of RVP is
uncommon”
ONLY Age >80 and history of AF were statistically significantly related to the
development of pacing need after implant
Kalantarian et al. Circulation. 2017;136:A19187

45. Baja incidencia de taquicardia ventricular
monomórfica en el seguimiento de SCD-HeFT
Of the 811 patients followed 45.5 months in SCD-HeFT
Total Patients
over 45.5
months
100%
Patients with
no therapy @
45.5 months
78%
Patients with
only VF or PVT
over 45.5
months
Patients with
only 1 MVT
over 45.5
months
Patients with
>1 MVT over
45.5 months
7%
7%
7%
The annualized risk that a patient had ANY MVT was 3.6% and the
annualized risk that a patient had multiple occurrences of MVT was 1.8%
Poole &. Gold. Circulation Arrh Electrophysiol. 2013;6:1236

46. Large randomized studies using contemporary programming
with long detection intervals has greatly reduced the number
of patients who receive ATP
Gasparini et al. JACC EP 2017 ;3:1275
7.0% 3.2%10.4%
4.8%
81.4%
90.8%
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
ADVANCE III - Control ADVANCE III - Long detection
ADVANCE III Appropriate Therapy by Type
ATP Only ATP & Shock Shock only No Therapy
16.7% 3.8% 1.6%
4.9%
3.8% 2.5%
77.8%
91.0% 94.4%
0.0%
10.0%
20.0%
30.0%
40.0%
50.0%
60.0%
70.0%
80.0%
90.0%
100.0%
Conventional Therapy High-Rate Therapy Delayed Therapy
MADIT RIT Appropriate Therapy By Type (1.4 year follow-up)
ATP Only ATP & Shock Shock Only No Therapy
Moss et al. N Engl J Med 2012; 367:2275

47. Adopción lenta?
Friedman et al. JAMA Cardiol 2016;1:900

48. Italian survey demonstrates disconnect between real
vs. perceived need for pacing
Botto et al. Europace 2017;19:1826

49. PRAETORIAN: estudio holandés, n=850, 2020
Nordkamp et al. Am Heart J 2012;163:753

50. MADIT S-ICD, post MI, DBT, >65, LVEF 36-50%
Kutyifa et al. Am Heart J 2017;189:158

51. Futuros desarrollos tecnológicos
• Defibrilador subesternal
• Desfibrilador SC acoplado a marcapasos leadless

52. Conclusiones
• El CDI subcutáneo es efectivo en detectar y terminar la TV/FV
• Tiene un menor riesgo de complicaciones severas que el CDI
• Debe considerarse en todo paciente con una indicación de CDI y sin
indicación para estimulación cardíaca
• Estudios randomizados en marcha van a solidificar el rol del CDI SC