A Major Determinant Focused on the ECG or Echocardiogram for Pacing-induced Cardiomyopathy (PICM) and Its Clinical Outcome (PICM Syndrome) : Prospective, Multi-center, Observational Cohort Study.

Chronic right ventricular pacing has a deleterious effect on left ventricular (LV) function, namely pacing-induced cardiomyopathy (PICM). Several parametes make difference of effect on the occurrence of PICM and its subsequent clinical outcomes. In particular, recognition of a major determinant focused on the ECG or echocardiographic parameters including strain or genetic factor for occurrence of PICM may lead to better identification of patients at high risk. Investigators prospectively enroll a participant with documented high risk of PICM and clinically follow-up to idenify clinical impact of PICM (PICM syndrome) over a long period of time.