Arrhythmias & electrophysiologyCohort study

Postapproval Study of a Subcutaneous Implantable Cardioverter-Defibrillator System

J Am Coll CardiolPublished

  • Prospective multicentre registry (post-approval study)
  • real-world
  • prespecified performance goals
  • 86 US centres

Authors' conclusion

In the largest prospective study of the S-ICD to date, all study endpoints were met, despite a cohort with more comorbidities than in most previous trials. Complication rates were low and shock efficacy was high. These results demonstrate the 5-year S-ICD safety and efficacy for a large, diverse cohort of S-ICD recipients.

Study context

Population
Patients with standard subcutaneous implantable cardioverter-defibrillator (S-ICD) indications at US centresmedian follow-up 4.2 years
Participants
1,643 patients
Outcome
Efficacy: first and final shock efficacy; safety: complications directly related to the S-ICD system or implantation procedure (assessed vs prespecified performance goals)
Follow-up
Up to 5 years

Main finding

As reported in the abstract

Shock efficacy for discrete VT or VF episodes

98.4%

Shock efficacy did not differ across follow-up years

P = 0.68

S-ICD-related complication-free rate

93.4%

Electrode-related complication-free rate

99.3%

Observational data: associations, not effects.

Further findings

Cumulative all-cause mortality

Cumulative all-cause mortality
21.7%

Safety

Device replaced by transvenous implantable cardioverter-defibrillator (TV-ICD) for pacing need

Patients with S-ICD replaced by TV-ICD for pacing need
1.6%

Original publication

Postapproval Study of a Subcutaneous Implantable Cardioverter-Defibrillator System. J Am Coll Cardiol. Published 1 August 2023. doi:10.1016/j.jacc.2023.05.034

Summarised from the published abstract; every number is checked against it