Physiologic Variants of Cardiac Conduction (Aberration, Gap, Supernormal Conduction)

Cardiol Clin. 2023 Aug;41(3):315-332. doi: 10.1016/j.ccl.2023.03.006.

Abstract

Wide QRS complexes during supraventricular rhythms can be caused by fixed bundle branch block, functional (intermittent) bundle branch block, preexcitation, or toxic/metabolic causes. Functional bundle branch block can be caused by long-short aberrancy (usually physiologic), or acceleration/deceleration dependent aberrancy (usually pathologic). Electrocardiogram criteria have been proposed to differentiate aberration from ventricular tachycardia; they are not always accurate. The gap phenomenon "paradox" is that with increasingly premature extrastimuli, progressive proximal conduction delay allows time for distal recovery of excitability. Supernormal conduction may explain unusual conduction phenomena in patients with abnormal His-Purkinje function or poorly conducting accessory pathways.

Keywords: Aberration; Bundle branch block; Gap phenomenon; Long-short aberration; Rate-dependent aberration; Supernormal conduction.

Publication types

  • Review

MeSH terms

  • Arrhythmias, Cardiac
  • Bundle-Branch Block* / diagnosis
  • Electrocardiography
  • Heart Conduction System*
  • Humans

Supplementary concepts

  • Hereditary bundle branch system defect