Abstract 13804: Correlation between Electrocardiographic Features and Local Activation Pattern in Arrhythmogenic Right Ventricular Dysplasia

Abstract

Background: Depolarization abnormalities in the terminal portion of the QRS are frequently seen in Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy (ARVD/C). The purpose of this study was to correlate the electroanatomic activation pattern of the RV endocardium and epicardium to the surface ECG. Methods: Thirty consecutive ARVD/C patients (Mean age 33.1 +/- 11.2 years, 16 (53%) men) underwent detailed endocardial and epicardial electroanatomical mapping (EAM). Local sinus rhythm activation was annotated at the sharpest intrinsic deflection of the bipolar electrogram, including late potentials. ECG features were classified into 5 major patterns; 1. Normal QRS (12 patients) 2. Epsilon wave (5 patients) 3. Incomplete RBBB (5 patients) 4. Atypical complete RBBB (6 patients) and 5. Prolonged terminal activation duration (TAD) (2 patients) Results: The earliest endocardial and epicardial RV activation occurred on the mid anteroseptal wall on all ECG patterns. Figure 1 represented activation area (purple) after the QRS or during the delayed depolarization phase. Nearly all endocardial and epicardial RV was activated well within the QRS duration in patients with normal QRS but was activated during R’ in patients with CRBBB. The delayed activation during Epsilon wave consistently occurred in basal anterior wall and basal angle of RV. In patients with TAD, the activation of RVOT and basal angle RV represented slurred S wave. Conclusion: ECG features in ARVD/C are correlated with late activation in specific regions of RV and total endocardial activation time. The delay activation of basal anterior wall and basal angle of RV represents the Epsilon wave in the right precordial ECG.