Studies of heart block with His bundle electrograms.

Studies of intra-atrial conduction with bipolar atrial and His electrograms.

With the use of His bundle electrograms, intra-atrial conduction delay has been found to be a cause offirstdegree heart block. Twenty-one patients with evidence of atrioventricular conduction defects or dysrhythmias were studied with His bundle electrograms and 2 were found to have delayed intra-atrial conduction while in sinus rhythm. A further 3 patients had normal PA intervals during sinus r...

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.

His Bundle electrogram in bundle-branch block.

SUMMARY Because a great majority of patients with chronic complete heart block have bilateral bundle-branch lesions, it becomes important to recognize earlier degrees of bilateral bundle-branch block. The H-V interval in the His bundle electrogram during unilateral bundle-branch block reflects the conduction primarily through the contralateral bundle branch, and thus the His bundle electrogram ...

Conduction intervals and conduction velocity in the human cardiac conduction system. Studies during open-heart surgery.

Specialized fiber electrograms were recorded in 64 patients during open-heart surgery. Intervals were measured from the proximal His bundle, distal His bundle, and right and left bundle branches to the earliest QRS deflection in the limb lead ECG (pH-Q, dH-Q, RB-Q, and LB-Q interval, respectively). There was an increase of pH-Q intervals with increasing age such that at age 3 months the normal ...

Bundle of His electrograms in congenital corrected transposition of the great arteries. A study of two adult cases.

His bundle electrograms were recorded in 2 adult cases of congenital corrected transposition of the great arteries. Both patients had prolonged HV conduction and a His potential that was wide. These findings are different from those reported in congenital atrioventricular block without ventricular inversion wherein an abnormality within the AHperiod has been found. It is suggested that these di...