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Updated: Jul 17, 2026

A Method for Tracking the Time Evolution of Steady-State Evoked Potentials
Published on: May 25, 2019
Dynamic effects of exercise and different escape rhythms on the supernormal period of an accessory pathway
1Department of Medicine, University of Hawaii, Honolulu, Hawaii, USA.
Abstract:
Spontaneous conduction during the supernormal period (SNP) of accessory pathways (AP) is rare and observed only during atrio-ventricular block (AVB). The effect of exercise and different escape rhythms on the SNP is unknown. We evaluated these factors on the SNP of a para-Hisian AP after a failed ablation complicated by AVB. The SNP onset and duration were later and longer during paced versus junctional rhythm. Exercise caused linear shortening of the SNP that was directly related to junctional cycle length. The SNP is a dynamic window shifting in parallel with AP refractoriness and affected by exercise and type of escape rhythm.
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