This study was designed to prospectively evaluate the risk–benefit ratio of implantable cardioverter defibrillator (ICD) therapy in young patients with cardiomyopathies and channelopathies.Methods and results
The study population included 96 consecutive patients [68 men, median age 27 (22–32) years] with cardiomyopathies, such as arrhythmogenic right ventricular cardiomyopathy (n = 35), dilated cardiomyopathy (n = 17), hypertrophic cardiomyopathy (n = 15), Brugada syndrome (n = 14), idiopathic ventricular fibrillation (n = 5), left ventricular noncompaction (n = 4), long-QT syndrome (n = 4) and short-QT syndrome (n = 2), who were 18–35 years old at the time of ICD implantation. During a mean follow-up of 72.6 ± 53.3 months, one patient with end-stage hypertrophic cardiomyopathy died because of acute heart failure, and 11 patients underwent orthotopic heart transplantation. Twenty patients (20.8%) had a total of 38 appropriate ICD interventions (4%/year), and 26 patients (27.1%) experienced a total of 49 adverse ICD-related events (5.4%/year), including 23 inappropriate ICD interventions occurring in nine patients (9.4%) and 26 device-related complications requiring surgical revision occurring in 20 patients (20.8%). Lead failure/fracture requiring lead extraction was the most common complication (n = 9). A threshold for ICD therapy less than 300 ms was associated with a borderline significant lower probability of inappropriate ICD interventions (hazard ratio = 0.2; 95% confidence interval 0.02–1.2; P = 0.07), whereas underweight status was an independent predictor of device-related complications (hazard ratio = 5.4; 95% confidence interval 1.5–19.4; P = 0.01).Conclusion
In young patients with cardiomyopathies and channelopathies, ICD therapy provided life-saving protection by effectively terminating life-threatening ventricular arrhythmias. However, because ICD-related adverse events are common, the risk/benefit ratio should be carefully assessed when considering ICD implantation in young people.