Left Ventricular Late Gadolinium Enhancement for Arrhythmic Risk Prediction in ARVC

BACKGROUND: – The arrhythmogenic right ventricular cardiomyopathy (ARVC) risk calculator estimates the risk of incident sustained ventricular arrhythmia (VA) and performs well in ARVC populations meeting 2010 Task Force Criteria. However, the calculator includes no measure of left ventricular (LV) structure and function, while late gadolinium enhancement (LGE) on cardiac magnetic resonance shows promise in arrhythmic risk prediction. This study aims to evaluate whether LV LGE on cardiac magnetic resonance can further refine ARVC VA risk stratification. METHODS: – Patients with definite ARVC, no prior sustained VA, and contrast-enhanced cardiac magnetic resonance at baseline were followed at 17 centers. Survival analyses were performed to assess LV LGE effect on VA prediction, and its incremental prognostic value on the risk calculator was evaluated using Cox proportional hazard models. The presence of high-risk LGE, defined as LV epicardial, transmural, and combined septal and free-wall LGE, was studied as a sensitivity analysis. RESULTS: – Of 385 patients (39.6±15.4 years, 39.7% male, 54.0% probands), 132 (34.3%) had LV LGE on cardiac magnetic resonance, with 98 (25.5%) having a high-risk pattern. Over 3.1 [1.2–5.8] years of follow-up, 67 (17.4%) patients experienced VA. In univariable analysis, both LV LGE (hazard ratio, 1.82; P=0.014) and high-risk LV LGE (hazard ratio, 1.85; P=0.017) were associated with higher risk for VA. However, after adjusting for the ARVC calculator–estimated risk, the presence of neither LV LGE (P=0.85) nor high-risk LV LGE (P=0.87) independently predicted sustained VA. CONCLUSIONS: – While associated with the risk of VA in ARVC, LV LGE did not provide incremental prognostic value for incident VA risk prediction compared with the ARVC risk calculator.