Abstract 19320: The Presence and Extent of Right Ventricular Electroanatomic Scar (by CARTO System) Predict the Outcome of Patients With Right Ventricular Arrhythmias
Background: Electroanatomic scars by CARTO system (i.e. low-voltage regions with bipolar electrogram <0.5 mV) (EAS), may represent the cardiomyopathic substrate of life-threatening right ventricular (RV) tachyarrhythmias. This study prospectively evaluated the prognostic value of RV-EAS in a cohort of patients presenting clinically with arrhythmias of RV origin.
Methods: The study population comprised 109 consecutive patients (73 men and 36 women; mean age 36±14 years) with a left bundle branch block pattern ventricular arrhythmia, such as sustained ventricular tachycardia (VT) in 21, non sustained VT in 64, frequent and/or repetitive premature ventricular beats in 94 patients. All patients underwent detailed clinical evaluation and high density (197±23 points) RV endocardial voltage mapping (EVM) to identify EAS. Sixty-three patients (58%) fulfilled the Task Force diagnostic criteria for arrhythmogenic RV cardiomyopathy/dysplasia (ARVC/D).
Results: EAS were found in 54 patients (49%), affecting 20.4% ±13 (range 2.6% to 49.8%) of the RV free wall. During a follow-up of 49±13 months, 25 of 109 patients (23%) had malignant arrhythmic events, such as sudden death in 2, cardiac arrest due to ventricular fibrillation in 4, appropriate ICD intervention in 7, and instable VT leading to syncope in 12. Kaplan-Meier analysis showed that syncope (long rank<0.001) and EAS (long rank<0.001) were significantly associated with arrhythmic events. After adjustement for age, family history, VT, RV dilatation/dysfunction and clinical diagnosis of ARVC/D, only unexplained syncope (OR=15.9;4.1–61.8;p<0.001) and EAS (OR=9.38;2.0–42.7;p=0.004) remained independent predictors of a malignant arrhythmic outcome. Among patients with an abnormal RV-EVM, those who experienced arrhythmic events during follow-up had a significantly grater extent of EAS (27.4±10.5% vs 16±12.3% p<0.001).
Conclusion: EAS were found in approximately half of patients with arrhythmias of RV origin. There was a significant correlation between presence and extent of EAS and incidence of arrhythmic events during follow-up. The presence of EAS, but no clinical diagnosis of ARVC/D and RV dilatation/dysfunction, was an independent predictor of malignant arrhythmic outcome.
- © 2010 by American Heart Association, Inc.