Briceño DF, Liang JJ, Shirai Y, et al. - In view of limited data characterizing structural changes of arrhythmogenic right ventricular (RV) cardiomyopathy, researchers here assessed patients presenting with left bundle branch block ventricular tachycardia in the setting of arrhythmogenic RV cardiomyopathy with procedures separated by at least 9 months. They included 19 consecutive patients (84% males; mean age 39±15 years [range, 20–76 years]) and made them undergo 2 detailed sinus rhythm electroanatomic endocardial voltage maps (average 385±177 points per map; range, 93–847 points). The mean time interval of 50±37 months (range, 9–162) was reported between the initial and repeat ablation procedures. Outcomes revealed an uncommon occurrence of > 10% increase in RV endocardial surface area of bipolar voltage consistent with scar among patients with arrhythmogenic RV cardiomyopathy presenting with recurrent ventricular tachycardia during the intermediate-term. Regions of prior defined scar were the most involved location in recurrent ventricular tachycardias. They observed an association of voltage indexed scar area at baseline, but not of changes in scar over time, with progressive increase in RV size; voltage indexed scar area remained consistent with adverse remodeling but not scar progression. Patients with arrhythmogenic RV cardiomyopathy who have progressive RV dilation frequently exhibit marked tricuspid regurgitation.