Result
During the median follow-up of 4.5 years, 50.0% (68/136) of patients experienced ≥ 1 episode, and 25.0% (34/136) of patients experienced ≥ 3 episodes of RR-NSVT. Event-free survival for VTAs was significantly higher in the RR-NSVT (+) group whereas those for heart failure admission and cardiovascular mortality were comparable between groups. In the multivariate cox regression analysis, any RR-NSVT showed a positive association with the occurrence of VTAs (HR: 5.087; 95% CI: 2.374-10.900; p<0.001). In RR-NSVT (+) patients, a cluster (≥ 3 times/6 months) and frequent pattern (≥ 3 runs/day) of RR-NSVT were observed in 42.6% (29/68) and 30.9% (21/68) of patients, respectively, who showed further increased incidence of VTAs.