Abstract 2256: Predictors of “Life-Threatening” Fast VT or VF in Arrhythmogenic Right Ventricular Dysplasia
Introduction: The Multidisciplinary Study of Right Ventricular Dysplasia is an NIH-funded, multicenter, prospective registry of patients meeting Task-Force criteria for arrhythmogenic right ventricular dysplasia (ARVD). Previous studies have used the occurrence of “life-threatening” fast VT or VF as a surrogate for sudden cardiac death in patients with an ICD, however the patient characteristics associated with sudden cardiac death in ARVD remain poorly defined.
Methods: All patients in the ARVD registry that underwent implantation of an ICD were studied. Baseline characteristics of patients who received ICD therapy for fast VT/VF (with a cycle length of <250msec) were compared to those patients who did not receive ICD therapy. The cumulative risk of appropriate ICD therapy for fast VT/VF was determined by the Kaplan-Meier method for patients receiving an ICD for primary or secondary prevention.
Results: 80 patients in the ARVD registry underwent implantation of an ICD. Of those, 61 patients (76%) had an ICD implanted for secondary prevention and 19 patients (24%) for primary prevention. Over a mean follow-up of 1.7 years, 17.5% of patients experienced appropriate ICD therapy for fast VT/VF, including 18% of patients with an ICD implanted for secondary prevention and 15.8% of patients with and ICD implanted for primary prevention. Among all baseline imaging, echocardiographic, and electrcardiographic characteristics, none were significantly associated with the occurance of fast VT/VF during follow-up. In a Kaplan-Meier analysis, there was no significant diffference in the cumulative risk of ICD therapy for fast VT/VF between primary or secondary prevention cohorts (log rank p-value = 0.69).
Conclusions: In this registry of patients meeting the current Task Force criteria for ARVD, there is a high incidence of “life-threatening” fast VT/VF during follow-up, and the probability of fast VT/VF is similar in patients with an ICD for secondary prevention compared to those with an ICD for primary prevention. Furthermore, baseline characteristics do not reliably predict a future risk of life threatening arrhythmias in this cohort.