Left axis deviation: a spectrum of intraventricular conduction block.

Study of intraventricular conduction times in patients with left bundle-branch block and left axis deviation and in patients with left bundle-branch block and normal QRS axis using His bundle electrograms.

Left Axis Deviation

The effects of left axis shift (> -30°) on intraventricular conduction time (IVCT) were studied in 63 subjects in whom electrocardiograms before and after appearance of the left axis shift were available. Subjects with electrocardiographic evidence of left or right ventricular hypertrophy, left or right bundle branch block, myocardial infarction, pre-excitation and those receiving antiarrthythm...

Left Axis Deviation

The effects of left axis shift (> -30°) on intraventricular conduction time (IVCT) were studied in 63 subjects in whom electrocardiograms before and after appearance of the left axis shift were available. Subjects with electrocardiographic evidence of left or right ventricular hypertrophy, left or right bundle branch block, myocardial infarction, pre-excitation and those receiving antiarrthythm...

Mahaim conduction producing left axis deviation and normal QRS.

An unusual patient is described in whom electrophysiological studies strongly suggest the occurrence of Mahaim conduction. The patient whose electrocardiogram previously showed a left anterior hemiblock pattern then developed advanced atrioventricular (AV) block (AH block). Beats conducted through the atrioventricular node always had a short HV interval (20 ms) and QRS complexes of left anterio...

Vectorcardiographic study of QRS loop in patients with left superior axis deviation and right bundle-branch block.

Thirty-four elderly patients with right bundle-branch block and left axis deviation were studied vectorcardiographically utilizing the McFee-Parungao system. Atherosclerosis, arterial hypertension, angina pectoris, cardiac enlargement, and heart failure were common clinical features in this series. Moreover, intermittent advanced degree of atrioventricular block was present in 10 out of the 34 ...