Abstract 13073: ECG, Clinical, and Imaging Characteristics of Arrhythmogenic Right Ventricular Cardiomyopathy With Fat and Fibrotic Invasion Into the Left Ventricular Myocardium Revealed by Four-dimensional (4D) Cardiac CT

Abstract

Introduction: 4D cardiac CT can reveal characteristics of arrhythmogenic right ventricular (RV) cardiomyopathy (ARVC) such as fat and fibrotic invasion into the RV and LV myocardium (RVM, LVM), an enlarged RV, reduced RV motion and bulging. Hypothesis: We could differentiate ARVC patients with fat and fibrotic invasion into the LVM from those without, using ECG, clinical, and other imaging characteristics. Methods: Retrospective analysis of 17 patients (11 males, 57±17 years) with suspected ARVC who underwent 4D cardiac CT. Results: 9 patients met the 2010 ARVC task force criteria. 4 had fat and fibrotic invasion into the LVM (group 1) but 5 did not (group 2). The remaining 8 did not fulfill the ARVC criteria (group 3). The proportion of males and age did not differ between groups. In groups 1, 2 and 3, respectively, 3 (75%), 4 (80%), and 1 (13%) patients had epsilon waves in V1-3 (group 1>3, P=0.033, group 2>3, P=0.005). 2 (50%), one (20%) and 4 (50%) had complete right bundle branch block (CRBBB) (all P=NS). Three (75%), 3 (60%), and 1 (13%) had inverted T waves in V1-3 or beyond (group 1>3, P=0.033). One (50%), 3 (75%), and 2 (50%) had terminal activation duration of QRS ≥55 ms measured from the nadir of the S wave to the end of the QRS, including R’, in V1, V2, or V3, in the absence of CRBBB (all P=NS). One (25%), 4 (80%) and 1 (13%) had sustained ventricular tachycardia (SVT; group 2>3, P=0.005). Two (50%), 1 (20%), and 3 (38%) had non-SVT (all P=NS). 4 (100%), 2 (40%), and 2 (25%) had clinical heart failure (group 1>2, P=0.019, group 1>3, P<0.001). Finally, 4 (100% and 80%) and 6 (75%) had RV enlargement on TTE (all P=NS). On 4D CT, 4 (100%), 5 (100%), and 5 (63%) of patients in groups 1, 2 and 3, showed RV enlargement (all P=NS); 4 (100%), 2 (40%), and 1 (13%) showed reduced RV motion (group 1>2, P=0.019, group 1>3, P<0.001); 75, 100, and 0%, had RV fat invasion (group 1>3, P=0.002, group 2>3, P<0.001); and 25, 0, and 0% showed bulging (all P=NS). Conclusions: Most patients had RV enlargement on TTE and/or 4D CT. Presence of epsilon waves, reduced RV motion, and RV fat invasion on 4D CT may differentiate groups 1 and 2 from group 3, inverted T waves in V1-3 leads or beyond may differentiate group 1 from group 3, SVT may differentiate group 2 from group 3 but only clinical heart failure may differentiate groups 1 and 2.