Sudden cardiac death (SCD) is among the most common types of mortality in developed countries. It for more deaths each year than the total number of deaths from AIDS, breast cancer, lung cancer and stroke together. SCD accounts for approximately 50% of all deaths from cardiovascular diseases and 20% of total mortality (1). In the general population, SCD mostly occurs in individuals who are unrecognized to be at risk (2,3). Although the causes of SCD are multiple, the majority (80–85%) of sudden cardiac deaths is caused by acute ventricular arrhythmias (4). Traditionally, the risk of ventricular arrhythmias has been evaluated based on the duration of QT interval on a standard surface ECG.