Heart failure & cardiomyopathies
International Experience With Implantable Cardioverter Defibrillators for the Prevention of Sudden Death in High-Risk Patients With Hypertrophic Cardiomyopathy
Authors' conclusion
In this international multicenter study, the largest to date, including >3300 consecutive patients with HCM and ICDs, device therapy terminated potentially lethal ventricular tachyarrhythmias in 1 of 6 patients, with low HCM-related mortality rates for patients with ICDs.
Study context
- Population
- Consecutive patients with hypertrophic cardiomyopathy with implanted cardioverter-defibrillators (ICDs) (1992 to 2024), 25 centres worldwide63% men
- Participants
- 3,387 patients
- Exposure
- Secondary prevention vs Primary prevention
- Secondary preventionn = 247
- Primary preventionn = 3,140
- Outcome
- Appropriate ICD therapy for life-threatening ventricular arrhythmias
- Follow-up
- 7±6 years (up to 32 years)
Methodological detailsmulticentre, international, 25 hypertrophic cardiomyopathy (HCM) centres, consecutive patients
- Multicentre
- International
- 25 HCM centres
- Consecutive patients
Main finding
As reported in the abstract
≥1 appropriate ICD therapy · 7±6 years
| Group | Value | Annual rate |
|---|---|---|
| Secondary prevention | 35% | 6.4%/y |
| Primary prevention | 15% | 2.2%/y |
Value
Secondary prevention35%
Primary prevention15%
Annual rate
Secondary prevention6.4%/y
Primary prevention2.2%/y
- Overall ≥1 appropriate ICD therapy: 550 patients (2.6%/y)
- 16%
Observational data: associations, not effects.
Further findings
- Mortality, primary prevention
- 6% · 194 of 3140
Primary prevention: timing of appropriate therapy
- Median time to first appropriate therapy after implantation
- 4 years
- First appropriate therapy ≥10 years after implantation
- 16%
- Multiple interventions
- 47%
Independent predictors of appropriate ICD therapy
- Unexplained syncope, LV apical aneurysms, LV systolic dysfunction, nonsustained VT on ambulatory monitoring
Survival free from HCM-related mortality · 10 and 20 years
- 10 years
- 97%
- 20 years
- 91%
Safety
Device failures in those with life-threatening ventricular tachyarrhythmias
- Device failures
- 2.4%
Original publication
International Experience With Implantable Cardioverter Defibrillators for the Prevention of Sudden Death in High-Risk Patients With Hypertrophic Cardiomyopathy. Circulation. Published 25 August 2026. doi:10.
Summarised from the published abstract; every number is checked against it