Figure 1From: Exercise-induced left bundle branch block and subsequent mechanical left ventricular dyssynchrony -resolved with pharmacological therapy 12-lead electrocardiogram. (A) 12-lead electrocardiogram taken at rest shows a QRS width of 88 ms. (B) 12-lead electrocardiogram after treadmill exercise test indicates a left bundle branch block with a QRS width of 152 ms at a heart rate of 100 bpm. (C) 12-lead electrocardiogram following the treadmill exercise test 5-month after pharmacological therapy does not show any a left bundle branch block at a heart rate of 126 bpm.Back to article page