The Wedensky effect in the human heart.

Open Access
Publisher Website
Google Scholar
Abstract
Intracardiac electrical stimulation was used in 7 patients with apparent complete heart block, for the purpose of determining whether the Wedensky effect could occur in the human heart. A specially constructed quadripolar catheter connected to 2 separate pacemakers was employed 4 times. A synchronized unit for paired and coupled electrical stimulation was used in the rest of the cases. Ventricular excitability was therefore studied in man under controlled conditions. A supernormal phase was detected 4 times. The Wedensky phenomenon, studied by a modification of Goldenberg and Rothberger''s technique, was seen in 2 patients. The analysis of the pause that follows cessation of rapid electrical stimulation after digitalization, experiments performed in dogs, and occasional clinical cases with A-V block and varying degrees of digitalis effect, seem to corroborate the hypothesis of other investigators that electrical simuli can produce, under certain conditions, secondary (late) responses in which the mechanism of vulnerability and supernormality cannot be invoked. Hence, a distrubance or excitability rather than an abnormally in conductivity (re-entry phenomenon) can best explain the origin of ventricular extrasystoles occurring late in the cycle.

This publication has 14 references indexed in Scilit: