Right Ventricular Strain and Dyssynchrony Assessment in Arrhythmogenic Right Ventricular Cardiomyopathy: A Cardiac Magnetic Resonance Feature-Tracking Study

Aim: Analysis of regional dysfunction by cardiac magnetic resonance (CMR) imaging in arrhythmogenic right ventricular cardiomyopathy (ARVC) may be inadequate due to the complex contraction pattern of the RV. Aim of the present study was to determine the utility of right ventricular (RV) strain and dyssynchrony assessment in ARVC using feature-tracking CMR analysis. Methods: Thirty-two consecutive patients with ARVC referred to CMR imaging were included. Thirty-two patients with idiopathic right ventricular outflow tract arrhythmias (RVOT-A) and 32 control subjects, matched for age and gender to the ARVC group, were included for comparison purpose. CMR imaging was performed to assess biventricular function; feature-tracking analysis was applied to the cine CMR images to assess regional and global longitudinal, circumferential and radial strain (GLS, GCS, GRS) and RV dyssynchrony (defined as the standard deviation of the time-to-peak strain of the RV segments; SD-TPS). Results: GLS (-17±5% vs.-26±6% vs.-29±6%; p<0.001), GCS (-9±4% vs. -12±4% vs. -13±5%; p=0.001) and GRS (18 [12-26]% vs. 22[15-32]% vs. 27[20-39]%; p=0.015) were significantly lower and SD-TPS in all three directions were significantly higher among ARVC patients compared to RVOT-A patients and controls. RV GLS>-23.19%, longitudinal SD-TPS>113.13ms and circumferential SD-TPS>177.11ms allowed correct identification of 88%, 75% and 63% of ARVC patients with no or only minor CMR criteria for ARVC diagnosis. Conclusions: Strain analysis by feature-tracking CMR helps to objectively quantify global and regional RV dysfunction and RV dyssynchrony in ARVC patients and provides incremental value over conventional CMR imaging.