B-PO05-023 RIGHT VENTRICULAR DILATION, DYSFUNCTION, AND TRICUSPID REGURGITATION IN PATIENTS WITH ARRHYTHMOGENIC RIGHT VENTRICULAR CARDIOMYOPATHY

Patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) frequently show progressive right ventricular dilation and dysfunction. Patients may also have substantial tricuspid regurgitation, particularly in the presence of transvenous implantable cardioverter-defibrillator (ICD) leads. We sought to evaluate the incidence of right ventricular dilation, dysfunction, and tricuspid regurgitation in a contemporary ARVC cohort. Patients with suspected ARVC underwent comprehensive clinical evaluations including standard and signal-averaged electrocardiogram, routine echocardiogram and cardiac magnetic resonance imaging (unless an ICD was present), as well as genetic testing for ARVC-related genes. Subgroups were compared by Fisher's exact test. A total of 52 patients met the 2010 task force criteria for definite ARVC. The median age was 47 years (interquartile range 29-62) and 56% were male. Echocardiography demonstrated normal RV size (35%), mild (24%), moderate (18%), and severe dilation (22%). RV function was normal (45%), mildly (29%), moderately (16%), or severely impaired (10%). Tricuspid regurgitation (TR) was quantified as trace or none (44%), mild (30%), moderate (18%), or severe (8%). Transvenous leads were present in 86%. 35 patients (67%) underwent genetic testing. Among those that underwent genetic testing, 14 patients (40%) had a PKP2 pathogenic variant and 4 patients (11%) had a DSP pathogenic variant. Variants of uncertain significance (VUS) were identified in DSP (n=4, 11%), PKP2 (n=1, 3%) and DSG (n=1, 3%). 11 patients (31%) had no pathogenic variant or VUS identified. All patients with severe TR had severe RV dilation and moderate-to-severe RV dysfunction. All patients with at least mild-to-moderate TR had a transvenous device lead present (p=0.093). There were no associations between pathogenic variants and RV dilation, dysfunction, or TR. Patients with ARVC frequently have RV dilation and dysfunction, and no effective therapy is available. Our data suggest a link between transvenous device leads and TR in patients with ARVC. Prospective lead management with either use of a subcutaneous ICD or tricuspid valve plication represents an actionable therapy to reduce TR.