Fig. 1

Twelve-lead surface ECG recording for one of our study population showing different patterns of QRS fragmentation in inferior, anterior, and lateral leads (R’ in V1, notched R wave in V2, notched S wave in II and V4–6). This patient was discovered to have CAE in LAD, LCX, and RCA by invasive CA. A magnified view of lead V3 is shown with 2 positive and 2 negative waves with a normal QRS complex duration