Arrhythmias in Fabry Cardiomyopathy

Background: Prior studies suggest that the incidence of ventricular arrhythmias is high in patients with Fabry cardiomyopathy. This study evaluated the incidence of significant arrhythmias in a series of patients with Fabry cardiomyopathy. Hypothesis: Arrhythmias are important causes of morbidity and mortality in Fabry Cardiomyopathy. Methods: This study was a retrospective chart review of 19 patients with known Fabry cardiomyopathy. Device interrogation reports were reviewed for those who had implantable devices. Electrocardiogram, Holter monitor, and event monitors were reviewed in those who did not have implantable devices. Results: Eighteen of nineteen patients were on enzyme replacement therapy (ERT). Nine (47%) out of 19 patients had implantable devices. Implant indications included symptomatic bradycardia, nonsustained ventricular tachycardia, conduction abnormalities, palpitations, and syncope. Mean follow-up in the patients with devices was 50 +/- 23 months. Two patients received implantable cardioverter-defibrillator (ICD) shocks, 1 of which was inappropriate for atrial fibrillation. Patients were paced in the atrium 71% +/- 37% of the time and paced in the ventricle 49% +/- 52% of the time. Four patients with devices were paced more than 95% of the time. Patients with an ICD had lower heart rates prior to ICD implant than the group that did not have devices (60 +/- 10 vs 78 +/- 16, P = 0.03). Of the patients without devices, only 1 had sudden cardiac death. Patients with implanted devices had higher left ventricular (LV) mass indices compared to patients without implanted devices (136 +/- 40 g/m2 vs 93 +/- 19 g/m2, P = 0.008). Conclusions: Significant ventricular arrhythmias are uncommon in patients with Fabry cardiomyopathy on ERT, but utilization of pacing is high. Sudden cardiac death in Fabry cardiomyopathy may be related to bradycardia. The authors have no funding, financial relationships, or conflicts of interest to disclose.