Log in to MyACC
Postapproval Study of a Subcutaneous ICD System
Quick Takes
- This large prospective postapproval study supports long-term safety and efficacy of the subcutaneous implantable cardioverter-defibrillator (S-ICD).
- Furthermore, complication rates were low, and shock efficacy was high and consistent throughout the 5-year follow-up.
- Additional studies are indicated to determine the safety and efficacy of hybrid modular systems that combine a leadless pacemaker for bradycardia and antitachycardia pacing with an S-ICD to extend this therapy to more patients.
Study Questions:
What is the long-term safety and efficacy of subcutaneous implantable cardioverter-defibrillator (S-ICD) use in a diverse population of patients and implantation centers?
Methods:
The investigators enrolled patients in 86 US centers with standard S-ICD indications and followed them for up to 5 years. Efficacy endpoints were first and final shock efficacy. Safety endpoints were complications directly related to the S-ICD system or implantation procedure. Endpoints were assessed using prespecified performance goals. Fine-Gray and Aalen-Johansen methods were used to estimate event rates for complications, appropriate shocks, and inappropriate shocks, and Kaplan–Meier analyses were used to estimate mortality rates.
Results:
A total of 1,643 patients were prospectively enrolled, with a median follow-up of 4.2 years. All prespecified safety and efficacy endpoint goals were met. Shock efficacy rates for discrete episodes of ventricular tachycardia (VT) or ventricular fibrillation (VF) were 98.4%, and did not differ significantly across follow-up years (p = 0.68). S-ICD related and electrode related complication-free rates were 93.4% and 99.3%, respectively. Only 1.6% of patients had their devices replaced by a transvenous ICD (TV-ICD) for a pacing need. Cumulative all-cause mortality was 21.7%.
Conclusions:
The authors report that the S-ICD is safe and effective for a large, diverse cohort of S-ICD recipients at 5 years.
Perspective:
This large prospective postapproval study of a patient cohort with more comorbidities supports long-term safety and efficacy of the S-ICD. Furthermore, despite many less experienced implanting centers, complication rates were low, and shock efficacy was high and consistent throughout the 5-year follow-up, for discrete and storm episodes and for monomorphic and polymorphic VT/VF. Additional studies are indicated to determine the safety and efficacy of hybrid modular systems that combine a leadless pacemaker for bradycardia and antitachycardia pacing with an S-ICD to extend this therapy to more patients.
Clinical Topics: Arrhythmias and Clinical EP, Heart Failure and Cardiomyopathies, Prevention, Implantable Devices, SCD/Ventricular Arrhythmias, Atrial Fibrillation/Supraventricular Arrhythmias, Acute Heart Failure
Keywords: Arrhythmias, Cardiac, Bradycardia, Defibrillators, Implantable, Heart Failure, Pacemaker, Artificial, Secondary Prevention, Shock, Tachycardia, Ventricular, Ventricular Fibrillation
< Back to Listings
