Repolarization and Activation Restitution Near Human Pulmonary Veins and Atrial Fibrillation Initiation
نویسنده
چکیده
Results Compared with paroxysmal AF, patients with persistent AF had shorter left atrial APD and effective refractory period (p 0.01). In paroxysmal AF, maximum left atrial APD restitution slope was 1.5 0.4; and 12 of 13 patients had slope 1 (p 0.001). In persistent AF, PACs encountered prolonged activation for a wider range of beats than in paroxysmal AF (p 0.01), which prolonged DI and flattened APD restitution (slope 0.7 0.2; p 0.001); no patient had APD restitution slope 1. A single PAC produced AF in 5 patients; in all, an APD restitution slope 1 caused extreme APD oscillations after the PAC, then AF.
منابع مشابه
Repolarization and activation restitution near human pulmonary veins and atrial fibrillation initiation: a mechanism for the initiation of atrial fibrillation by premature beats.
OBJECTIVES The authors sought to study mechanisms to explain why single premature atrial complexes (PACs) from the pulmonary veins (PVs) may initiate human atrial fibrillation (AF). BACKGROUND Theoretically, single PACs may initiate AF if the rate response of action potential duration (APD) restitution has a slope >1. However, human left atrial APD restitution and its relationship to AF have ...
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