If the QRS complex is widened and downwardly deflected in lead V1, a left bundle branch block is present ... The ECG strip below shows normal sinus rhythm, then atrial fibrillation with a rapid ...

LBBP is defined as capturing the left bundle branch (LBB) trunk or its fascicles, whereas capturing only the left septal ...

The ECG findings presented as normal in athletes were established by an international ... and the QRS complex usually narrow unless the baseline QRS has a bundle branch block. Sinus rhythm resumes ...

Note that the ST segments in V4 and V5 are dramatically elevated in a shape different than a normal paced ... validated in a paced rhythm (see left bundle branch block review for more details).