Transmembrane potentials from the penetrating and branching portions of the bundle of His were simultaneously recorded along with bipolar extracellular electrograms. Recordings were obtained during periods of normal antegrade and retrograde conduction and also during various degrees of conduction delay and block within and distal to the bundle of His. The onset and ternination of extracellular ...

Paced QRS morphology should be assessed to differentiate between complete loss of His bundle capture and loss of distal His bundle capture alone. This might be enough in patients with proximal right bundle branch block; however, in patients with proximal left bundle branch block, QRS morphology might be similar with loss of His bundle capture and with proximal His bundle capture. Introduction T...

CHEST, 73: 3, MARCH, 1978 of the graphic records of different adventitious sounds are easily seen, but specific features characteristic of fine crackles or rhonchi, for example, cannot be readily identified. When adventitious sounds originate from multiple sites and produce a cascade of sounds, conventional recording techniques do not allow graphic representation of individual crackles or wheez...

gram. Tachyeardias originating in the left bundle branch and documented by right, left, and His bundle recordings have been produced in animals given excessive digitalis. We have noted a similar tachycardia in a patient with ischemic heart disease receiving digitalis during hypokalemia. The QRS complexes were 0.10 sec in duration and by contour suggested an ectopic focus located in the posterio...