Subcutaneous implantable cardioverter defibrillator in patients with hypertrophic cardiomyopathy

An initial experience

Jonathan Weinstock, Yousef H. Bader, Martin S. Maron, Ethan J. Rowin, Mark S. Link

Research output: Contribution to journalArticle

22 Citations (Scopus)

Abstract

Background-The subcutaneous implantable cardioverter defibrillator (S-ICD) has been developed to avert risks associated with transvenous defibrillator leads. The technology is attractive for younger patients, such as those with hypertrophic cardiomyopathy (HCM). However, there are limited data on S-ICD use in HCM. Methods and Results-HCM patients identified at risk for sudden death were considered for S-ICD implantation. Patients were screened for potential oversensing by surface electrocardiography (ECG). At implant, defibrillation threshold (DFT) testing was performed at 65, 50, and 35 joules (J). Twenty-seven patients were considered for S-ICD implantation, and after screening, 23 (85%) remained eligible. The presence of a bundle branch block was associated with screening failure, whereas elevated body mass index (BMI) showed a trend toward association. One patient passed screening at rest, but failed with an ECG obtained after exercise. At implant, the S-ICD terminated ventricular fibrillation (VF) with a 65J shock in all 15 implanted patients and a 50J shock was successful in 12 of 15. A 35J shock terminated VF in 10 of 12 patients. DFT failure at 50 J was associated with a higher BMI. There were no appropriate shocks after a median follow-up of 17.5 (3-35) months, and 1 patient received an inappropriate shock attributable to a temporary reduction in QRS amplitude while bending forward, resulting in oversensing, despite successful screening. Conclusions-In a high-risk HCM cohort without a pacing indication referred for consideration of an ICD, the majority were eligible for S-ICD. The S-ICD is effective at recognizing and terminating VF at implant with a wide safety margin.

Original languageEnglish (US)
Article number2488
JournalJournal of the American Heart Association
Volume5
Issue number2
DOIs
StatePublished - Jan 1 2016

Fingerprint

Implantable Defibrillators
Hypertrophic Cardiomyopathy
Shock
Ventricular Fibrillation
Electrocardiography
Body Mass Index
Defibrillators
Bundle-Branch Block
Sudden Death
Exercise
Technology
Safety

Keywords

  • Defibrillation
  • Hypertrophic cardiomyopathy
  • Implantable defibrillator
  • Sudden death

ASJC Scopus subject areas

  • Cardiology and Cardiovascular Medicine

Cite this

Subcutaneous implantable cardioverter defibrillator in patients with hypertrophic cardiomyopathy : An initial experience. / Weinstock, Jonathan; Bader, Yousef H.; Maron, Martin S.; Rowin, Ethan J.; Link, Mark S.

In: Journal of the American Heart Association, Vol. 5, No. 2, 2488, 01.01.2016.

Research output: Contribution to journalArticle

@article{ebe19a9d96944328b4643009ed888bab,
title = "Subcutaneous implantable cardioverter defibrillator in patients with hypertrophic cardiomyopathy: An initial experience",
abstract = "Background-The subcutaneous implantable cardioverter defibrillator (S-ICD) has been developed to avert risks associated with transvenous defibrillator leads. The technology is attractive for younger patients, such as those with hypertrophic cardiomyopathy (HCM). However, there are limited data on S-ICD use in HCM. Methods and Results-HCM patients identified at risk for sudden death were considered for S-ICD implantation. Patients were screened for potential oversensing by surface electrocardiography (ECG). At implant, defibrillation threshold (DFT) testing was performed at 65, 50, and 35 joules (J). Twenty-seven patients were considered for S-ICD implantation, and after screening, 23 (85{\%}) remained eligible. The presence of a bundle branch block was associated with screening failure, whereas elevated body mass index (BMI) showed a trend toward association. One patient passed screening at rest, but failed with an ECG obtained after exercise. At implant, the S-ICD terminated ventricular fibrillation (VF) with a 65J shock in all 15 implanted patients and a 50J shock was successful in 12 of 15. A 35J shock terminated VF in 10 of 12 patients. DFT failure at 50 J was associated with a higher BMI. There were no appropriate shocks after a median follow-up of 17.5 (3-35) months, and 1 patient received an inappropriate shock attributable to a temporary reduction in QRS amplitude while bending forward, resulting in oversensing, despite successful screening. Conclusions-In a high-risk HCM cohort without a pacing indication referred for consideration of an ICD, the majority were eligible for S-ICD. The S-ICD is effective at recognizing and terminating VF at implant with a wide safety margin.",
keywords = "Defibrillation, Hypertrophic cardiomyopathy, Implantable defibrillator, Sudden death",
author = "Jonathan Weinstock and Bader, {Yousef H.} and Maron, {Martin S.} and Rowin, {Ethan J.} and Link, {Mark S.}",
year = "2016",
month = "1",
day = "1",
doi = "10.1161/JAHA.115.002488",
language = "English (US)",
volume = "5",
journal = "Journal of the American Heart Association",
issn = "2047-9980",
publisher = "Wiley-Blackwell",
number = "2",

}

TY - JOUR

T1 - Subcutaneous implantable cardioverter defibrillator in patients with hypertrophic cardiomyopathy

T2 - An initial experience

AU - Weinstock, Jonathan

AU - Bader, Yousef H.

AU - Maron, Martin S.

AU - Rowin, Ethan J.

AU - Link, Mark S.

PY - 2016/1/1

Y1 - 2016/1/1

N2 - Background-The subcutaneous implantable cardioverter defibrillator (S-ICD) has been developed to avert risks associated with transvenous defibrillator leads. The technology is attractive for younger patients, such as those with hypertrophic cardiomyopathy (HCM). However, there are limited data on S-ICD use in HCM. Methods and Results-HCM patients identified at risk for sudden death were considered for S-ICD implantation. Patients were screened for potential oversensing by surface electrocardiography (ECG). At implant, defibrillation threshold (DFT) testing was performed at 65, 50, and 35 joules (J). Twenty-seven patients were considered for S-ICD implantation, and after screening, 23 (85%) remained eligible. The presence of a bundle branch block was associated with screening failure, whereas elevated body mass index (BMI) showed a trend toward association. One patient passed screening at rest, but failed with an ECG obtained after exercise. At implant, the S-ICD terminated ventricular fibrillation (VF) with a 65J shock in all 15 implanted patients and a 50J shock was successful in 12 of 15. A 35J shock terminated VF in 10 of 12 patients. DFT failure at 50 J was associated with a higher BMI. There were no appropriate shocks after a median follow-up of 17.5 (3-35) months, and 1 patient received an inappropriate shock attributable to a temporary reduction in QRS amplitude while bending forward, resulting in oversensing, despite successful screening. Conclusions-In a high-risk HCM cohort without a pacing indication referred for consideration of an ICD, the majority were eligible for S-ICD. The S-ICD is effective at recognizing and terminating VF at implant with a wide safety margin.

AB - Background-The subcutaneous implantable cardioverter defibrillator (S-ICD) has been developed to avert risks associated with transvenous defibrillator leads. The technology is attractive for younger patients, such as those with hypertrophic cardiomyopathy (HCM). However, there are limited data on S-ICD use in HCM. Methods and Results-HCM patients identified at risk for sudden death were considered for S-ICD implantation. Patients were screened for potential oversensing by surface electrocardiography (ECG). At implant, defibrillation threshold (DFT) testing was performed at 65, 50, and 35 joules (J). Twenty-seven patients were considered for S-ICD implantation, and after screening, 23 (85%) remained eligible. The presence of a bundle branch block was associated with screening failure, whereas elevated body mass index (BMI) showed a trend toward association. One patient passed screening at rest, but failed with an ECG obtained after exercise. At implant, the S-ICD terminated ventricular fibrillation (VF) with a 65J shock in all 15 implanted patients and a 50J shock was successful in 12 of 15. A 35J shock terminated VF in 10 of 12 patients. DFT failure at 50 J was associated with a higher BMI. There were no appropriate shocks after a median follow-up of 17.5 (3-35) months, and 1 patient received an inappropriate shock attributable to a temporary reduction in QRS amplitude while bending forward, resulting in oversensing, despite successful screening. Conclusions-In a high-risk HCM cohort without a pacing indication referred for consideration of an ICD, the majority were eligible for S-ICD. The S-ICD is effective at recognizing and terminating VF at implant with a wide safety margin.

KW - Defibrillation

KW - Hypertrophic cardiomyopathy

KW - Implantable defibrillator

KW - Sudden death

UR - http://www.scopus.com/inward/record.url?scp=85002152621&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85002152621&partnerID=8YFLogxK

U2 - 10.1161/JAHA.115.002488

DO - 10.1161/JAHA.115.002488

M3 - Article

VL - 5

JO - Journal of the American Heart Association

JF - Journal of the American Heart Association

SN - 2047-9980

IS - 2

M1 - 2488

ER -