Use of implantable cardioverter-defibrillator in inherited arrhythmogenic diseases: data from Italian ICD Registry for the years 2001-6.

Background: Previous studies have demonstrated the lifesaving role of an implantable cardioverter-defibrillator (ICD) in high-risk patients with genetic arrhythmogenic diseases.
Aim: To evaluate the clinical data of patients with hypertrophic cardiomyopathy (HCM), arrhythmogenic right ventricular cardiomyopathy (ARVD/C), idiopathic ventricular arrhythmia (IDIO-VA) including Brugada syndrome, short QT syndrome, and long QT syndrome (LQT) enrolled in the Italian ICD Registry in the years 2001-6.
Methods: The survey collected prospectively clinical data and technical characteristics of ICD implants on the basis of EURID form.
Results: The number of patients was 1,274 in the HCM group, 520 in the ARVD/C group, 460 in the IDIO-VA group, and 245 in the LQT group. Primary prevention involved 29.5% of patients in the HCM group, 15.9% in the ARVD/C group, 16.9% in the IDIO-VA group, and 16.6% in the LQT group, respectively. Ventricular tachycardia and ventricular fibrillation were reported in 49.0% and 24.8% in the HCM group, 72.9% and 20.0% in the ARVD/C group, 48.2% and 42.9% in the IDIO-VA group, and 21.2% and 61.6% in the LQT group, respectively. Single-, dual-, and triple-chamber ICDs were implanted in 41.5%, 47.6%, and 10.9% in the HCM group; 57.9%, 36.7%, and 5.4% in the ARVD/C group; 55.0%, 45.0%, and 0% in the IDIO-VA group; and 57.4%, 42.6%, and 0% in LQT group, respectively.
Conclusion: ICD therapies in the years 2001-6 for patients with inherited arrhythmia syndromes were utilized in Italy in a still-limited number of patients. Secondary prevention represented the major indication for ICD implant and the majority of patients were treated by single-chamber ICDs.