Chapman’s sign is used to diagnose an acute myocardial infarction in the setting of a left bundle branch block and consists of a notch in the upslope of the R wave in lead I, aVL or V6.

However, unlike in the presence of a left bundle branch block, myocardial ischemia and infarction can easily be detected on ECG when a RBBB is present. Below is an ECG displaying a right bundle ...