Dec 1, 1976

Preceding His-atrial interval as a determinant of atrioventricular nodal conduction time in the human and rabbit heart

The American Journal of Cardiology
J Billette

Abstract

This investigation shows that atrioventricular (A-V) nodal conduction time (A-H interval), both in the human and in the isolated rabbit heart, is determined mainly by the length of the preceding His-atrial (H-A) interval. The A-H intervals obtained during atrial extrasystolic stimulation at different basic rates, during Wenckebach cycles and during both transient and steady state responses to stepwise increases in stimulation frequency were plotted against the corresponding H-A intervals. The A-H intervals were found to have nearly the same duration provided they were preceded by the same H-A interval. The only important difference appeared in the short H-A interval range as a shortening of the A-H interval at faster basic rates. This facilitating effect of frequency, which was found in the majority of cases, is compatible with the similarly frequency-dependent shortening of the functional refractory period of the A-V node.

Mentioned in this Paper

Left Bundle Branch of His
Refractory Period
Cardiac Conduction System
Structure of Atrioventricular Node
NODAL gene
Heart Atrium
Cardiac Conduction
Electrocardiographic Recorders
Electric Stimulation Technique

About this Paper

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