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Updated: Aug 18, 2026

Three-Dimensional Modeling of the Left Atrium and Pulmonary Veins with a Precise Intracardiac Echocardiography Approach
04:29

Three-Dimensional Modeling of the Left Atrium and Pulmonary Veins with a Precise Intracardiac Echocardiography Approach

Published on: June 30, 2023

Premature depolarization concealed in two pulmonary veins

D Schwartzman1

  • 1Atrial Arrhythmia Center, University of Pittsburgh, Pennsylvania 15213-2582, USA. schwartzmand@msx.upmc.edu

Journal of Cardiovascular Electrophysiology
|September 2, 2000
PubMed

A case is presented in which a premature depolarization emanated from a partially activated left inferior pulmonary vein, activated the entire left superior pulmonary vein, but did not activate the atria ("concealed"). The site of conduction block between each vein and the left atrium was the anatomic atriovenous junction. At times, the same depolarization would activate the atria and initiate atrial fibrillation. The shortest depolarization coupling interval that activated the atria was significantly longer than the atrial fibrillation cycle length recorded in either vein. Observations in this case support two concepts: (1) the existence of myocardial "tracts," extending into and between pulmonary veins; and (2) a "mismatch" between pulmonary vein activation ingress and egress.

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