Figure 1. The two major patterns of early repolarization Figure 1. The two major patterns of early repolarization. Terminal QRS slurring (left) and notching (right) (arrows)

Figure 2. Schematic representation of the possible mechanism underlying J-wave occurrence. Action potentials from epicardium and endocardium from normal individuals (left) and early repolarization (ER) patients (right) as well as the respective electrocardiograms are shown. A prominent phase 1- notch and the loss of epicardial dome in phase-2 (red arrow) results in transmural dispersion of repolarization (dashed arrows) and appearance of the J-wave and ST-segment elevation on the surface ECG. AP: action potential, ECG: electrocardiogram, ER: early repolarization, RP: resting potential AP ECG Normal individual ER patient Endocardial AP Epicardial AP RP J- wave

(a) (b) Figure 3. Characteristic electrocardiograms (ECGs) of Brugada type I (a) and type II (b)

Table 1. High-risk criteria from clinical and laboratory evaluation Probable Male gender History of syncope History of familial SCD ER in inferior leads or global ER pattern Terminal notching of QRS complex J-wave amplitude >0.2mV Possible EPS Genetic Testing ECG markers of TDR ECG: electrocardiogram, EPS: electrophysiological study, ER: early repolarization, TDR: transmural dispersion of repolarization