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Updated: Mar 12, 2026

Optocardiography and Electrophysiology Studies of Ex Vivo Langendorff-perfused Hearts
Published on: November 7, 2019
Wenckebach Phenomenon in the His-Purkinje System
1Aurora Cardiovascular Services, Aurora Sinai/Aurora St. Luke's Medical Centers, University of Wisconsin School of Medicine and Public Health, 2801 West Kinnickinnic River Parkway, Suite 777, Milwaukee, WI 53215, USA.
Abstract:
The author discusses Wenckebach phenomenon (WP) in the His-Purkinje system (HPS). Subtle PR changes may be interpreted as no change, often seen in the HPS-WP. Changes in the QRS axis help to localize the site of delay and block along fascicles of the left bundle branch. Marked PR changes may occur during HPS-WP. All the QRS complexes that are conducted depict right bundle branch and left anterior superior fascicular block, so the visible changes in the HV interval suggest WP mostly occurring in the left posterior inferior fascicle.
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