Long-Term Outcome of ICD Therapy in Patients With Noncompaction Cardiomyopathy Compared With DCM and HCM

Background: Implantable cardioverter-defibrillators (ICDs) are frequently used for primary and secondary prevention in patients with cardiomyopathies due to different etiologies. However, long-term outcome studies in patients with noncompaction cardiomyopathy (NCCM) are scarce. Objectives: This study summarizes the long-term outcome of ICD therapy in patients with NCCM compared with those with dilated cardiomyopathy (DCM) or hypertrophic cardiomyopathy (HCM). Methods: Prospective data from our single-center ICD registry were used to analyze the ICD interventions and survival in patients with NCCM (n = 68) compared with patients with DCM (n = 458) and patients with HCM (n = 158) from January 2005 to January 2018. Results: This NCCM population with an ICD for primary prevention comprised 56 (82%) patients with a median age of 43 years and 52% males, compared with 85% in patients with DCM and 79% in patients with HCM (P = 0.20). During a median follow-up of 5 years (IQR: 2.0-6.9 years), appropriate and inappropriate ICD interventions were not significantly different. Nonsustained ventricular tachycardia during Holter monitoring in patients with NCCM was the only significant risk factor for appropriate ICD therapy in patients with NCCM, with a HR of 5.29 (95% CI: 1.12-24.96). The long-term survival was significantly better in the univariable analysis in the NCCM group. However, there was no difference in multivariable Cox regression analyses between the cardiomyopathy groups. Conclusions: At 5 years of follow-up, the rate of appropriate and inappropriate ICD interventions in NCCM was comparable to that in DCM or HCM. In multivariable analysis, no differences in survival were found between the cardiomyopathy groups.