ICD USE IN ARRHYTHMOGENIC RIGHT VENTRICULAR CARDIOMYOPATHY: PROPHYLACTIC V SECONDARY INDICATION

Abstract

Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) causes fibro-fatty scarring predominantly in the right ventricle and can lead to ventricular arrhythmias and sudden death. The role of prophylactic ICD therapy is unknown. We report our long-term follow-up of ICD use for prophylactic and secondary indications in a cohort of patients with ARVC. A retrospective chart review of all ARVC patients undergoing ICD implantation at a tertiary care center was performed, including both primary and secondary indications. Primary prevention ICDs were implanted based on suspected risk factors associated with an increased risk for sudden death including: sudden death in a first degree relative, marked RV involvement, LV involvement or TMEM43 genetic mutation. Patients with less than one year follow-up were excluded. All ICD events were adjudicated by two electrophysiologists. 48 ARVC patients at our centre were included. Diagnosis of ARVC was made between the ages of 9.8 to 70.2 (mean 40.1) years in 31 males and 17 females. Follow-up after ICD implantation was for a mean of 9.5 years (range 1 - 20.3 yrs). ICD was indicated secondary to VT/VF in 19 (39.6%) and prophylactic in 29 (60.4%) pts. The table shows the results. Thirteen of 19 (68.4%) patients with prior VT/VF had appropriate ICD use due to recurrence of sustained VT or VF. Four of 29 (13.8%) of primary prophylactic patients had appropriate ICD use. The prophylactic group is divided into those with (12) and those without (17) the TMEM43 genetic mutation. Three of the 12 TMEM43 mutation group had ICD use (25%). One of the non TMEM43 pts of the prophylactic group (1 of 17; 5.8%) had ICD use. Two patients underwent cardiac transplantation. Nine secondary ICD patients and one prophylactic patient had catheter ablation for frequent VT/VF. There was one death (post bone marrow transplantation for leukemia). ARVC patients with secondary ICD implantation for VT/VF had very frequent VT/VF recurrence with appropriate ICD use. Prophylactic ICD patients had VT/VF treated by ICD less frequently (13%) over 8.7 years of follow-up. Appropriate prophylactic ICD use was common with TMEM43 genetic mutation (25%). Primary prophylactic ICD use in ARVC patients without TMEM43 mutations requires further evaluation of risk factors for sudden death and outcomes with ICD use.