Background: The presence of J wave in arrhythmogenic right ventricular cardiomyopathy (ARVC) is associated with fatal ventricular arrhythmias. A recent study showed that J wave can be caused by either depolarization or repolarization abnormalities.
Objective: This study aims to evaluate the depolarization pattern in patients with ARVC concomitant to the presence of J wave
Methods: Patients with definite ARVC undergoing endocardial and epicardial substrate mapping were enrolled and classified into two groups based on the presence of J wave. The substrate characteristics and distribution of late potential (LP) area were analyzed
Results: A total of 42 patients were studied, including 12 (28.6%) with J wave and 29 (69%) without. All patients had J wave in inferior leads. Baseline characteristics and electrophysiological parameter regarding the total activation time, low-voltage zone (LVZ), scar area was similar between these two groups. A total of 51 and 58 LP area in 71 regions was identified in the endocardium and epicardium, respectively. The concordance of endo/epi LP area was found in 38 (53.5%) region and discordance in 33 (46.5%) region. Patients with J (+) ARVC had more discordant LP area than J (-) ARVC (100% vs. 10%). Completed endo/epicardial LPs elimination resulted in the disappearance of J wave in 3 (25%) patients with J (+) and similar ventricular arrhythmia recurrence between two groups.
Conclusion: Inferior endo/epi transmural activation discrepancy frequently leads to presence of J wave in ARVC, which proves the mechanistic insight of depolarization on J wave.