IJCS | Volume 32, Nº5, September/October 2019

543 Cont. Figure 1 - ECG before exercise demonstrating sinus rhythm and first-degree atrioventricular block and left anterior fascicular block (A). At the 5 th minute of exercise, the ECG showed a LBBB with a QRS width of 120 ms (B). ECG at 3:52 min into recovery phase demonstrating the disappearance of the LBBB (C). Gazzilli et al. Stress-induced left bundle branch block Int J Cardiovasc Sci. 2019;32(5):540-545 Case Report