Abstract 15236: Mode of Initiation and Timing of Spontaneous Ventricular Arrhythmias in Patients With Arrhythmogenic Right Ventricular Cardiomyopathy
Introduction: We evaluated the mode of initiation and circadian patterns of spontaneous malignant ventricular arrhythmias VAs in patients with arrhythmogenic right ventricular cardiomyopathy ARVC analyzing stored intracardiac electrograms (EGMs) from implantable cardioverter-defibrillator (ICD) given that has not been previously investigated.
Methods: We analyzed 373 VA episodes from 33 patients meeting revised Task Force criteria for ARVC. VAs were classified as sustained ventricular tachycardia (VT) (leading to appropriate ICD intervention or lasting more than 30 seconds if spontaneously terminated), non-sustained VT (NSVT) (self-terminating and lasting less than 30s) and polymorphic VT/ventricular fibrillation (VF). For each episode the cycle length (CL), preceding rhythm and rate, mode of onset, mode of termination and time of day were determined. VT onset was classified into two groups based on the initiation pattern: (1) sudden onset (when the first beat of VT was morphologically similar to the subsequent tachycardia), (2) premature ventricular complex (PVC) initiated (when the first beat of VT was morphologically different from subsequent VT).
Results: Out of 373 VA episodes, 39% were NSVT, 58% sustained monomorphic VT, and 3% VF. Sinus tachycardia (ST) or atrial fibrillation (AF) with rapid ventricular response (CL≤600 ms) preceded VA onset in 25% and 47% of the sustained VT/VF and NSVT episodes, respectively (p<0.0001), while 17% and 9% were preceded by bradycardia (CL>1000 ms, either sinus or AF, p=0.030). The VA had a PVC onset in 76% cases, while a sudden onset occurred in the remaining 24%. Most (77%) of the VA episodes occurred during day-time (7:00-23:00), with only 23% of them occurring between 23:00 and 7:00. Compared to VA episodes with PVC onset, episodes with a sudden onset were more commonly preceded by ST or rapid AF, 91% vs. 15% (p<0.0001) and occurred more frequently during the day, 86% vs 75% (p=0.035).
Conclusion: In patients with ARVC, the majority of spontaneous VA events are initiated by a PVC. A sudden VA onset is observed in one fourth of cases and preceded by sinus tachycardia or rapid AF. These observations suggest potential roles for PVC suppression and autonomic modulation to reduce VA events in ARVC patients.
Author Disclosures: S.A. Castro: None. P. Santangeli: None. D. Muser: None. S. Magnani: None. R. Pathak: None. J. Liang: None. F.C. Garcia: None. B. Desjardins: None. M.D. Hutchinson: None. G. Supple: None. D.S. Frankel: None. D. Lin: None. R. Schaller: None. S. Dixit: None. D.J. Callans: None. E. Zado: None. M.P. Riley: None. F. Marchlinski: None.
- © 2016 by American Heart Association, Inc.