Implanted defibrillators in young hypertrophic cardiomyopathy patients: a multicenter study

Area of Science:

• Cardiology
• Genetics
• Medical Devices

Background:

• Hypertrophic cardiomyopathy (HCM) is a common genetic heart disease with a 1% annual sudden cardiac death (SCD) risk.
• Data on SCD risk and implantable cardioverter-defibrillator (ICD) use in young HCM patients are limited.

Purpose of the Study:

• To evaluate the efficacy and safety of ICDs in patients under 30 with HCM.
• To identify risk factors for appropriate and inappropriate shocks in this young population.

Main Methods:

• Retrospective study of 73 HCM patients (99 ICDs) implanted between 1995-2009 at five institutions.
• Analysis of appropriate/inappropriate shocks, complications, and mortality.
• Comparison of early vs. later decade implantation trends.

Main Results:

• 11% of patients experienced appropriate shocks; conventional SCD risk factors were not predictive.
• 22% experienced inappropriate shocks, with older age at implant a protective factor.
• 32% had late complications; 4% mortality, including one arrhythmic SCD.

Conclusions:

• ICD use in young HCM patients is shifting towards primary prevention.
• Shock rates are comparable to adult HCM populations, but device complications are substantial.
• Further research is needed to optimize ICD therapy in young HCM patients.