Correlation of Ventricular Arrhythmias With Genotype in Arrhythmogenic Right Ventricular Cardiomyopathy

Background— Although mutations of several genes are associated with arrhythmogenic right ventricular cardiomyopathy (ARVC), the exact correlation between genotype and ventricular arrhythmia features remains unclear. This study was aimed to examine the possible association of the 9 known genes of ARVC with clinical and electrophysiological characteristics. Methods and Results— Ninety subjects diagnosed with ARVC who underwent electrophysiological study were recruited for screening the 9 known ARVC-causing genes. A total of 53 mutations were identified in 57 (63%) subjects. Mutation carriers had more frequent clinical ventricular tachycardia (VT; 89% versus 55%; P <0.001) and negative T waves in V 1 to V 3 (61% versus 33%; P =0.016). Subjects with plakophilin-2 ( PKP2 ) mutations also had more frequent VT than those without mutations in PKP2 . Comparison between subjects with multiple and single mutations showed that syncope occurred more often in the former group (58% versus 24%; P =0.018). VT was significantly more often induced in mutation carriers compared with noncarriers (75% versus 39%; P =0.001), as well as in PKP2 mutation carriers compared with subjects without PKP2 mutations (80% versus 48%; P =0.002). Induced VT with a rate ≥200 bpm was more often documented in mutation carriers (88% versus 54%; P =0.013), as well as in PKP2 mutation carriers (91% versus 67%; P =0.041). Conclusions— Pathogenic gene mutations were found in nearly two thirds of subjects diagnosed with ARVC. Mutation carriers, especially PKP2 , had a higher proportion of a history of VT and more inducible fast VT.