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Alterations in atrial electrophysiology associated with chronic atrial fibrillation in man

K Kamalvand1, K Tan, G Lloyd

  • 1Department of Cardiology, Guy's Hospital, London, U.K.

European Heart Journal
|May 18, 1999
PubMed

Insights

Chronic persistent atrial fibrillation (AF) disrupts normal atrial electrophysiology. Patients with AF lose the typical longer refractory period at the right atrial appendage, increasing recurrence risk after cardioversion.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Atrial Fibrillation Research

Background:

  • Atrial fibrillation (AF) is a common arrhythmia with complex electrophysiological changes.
  • Understanding atrial electrophysiology in chronic persistent AF is crucial for improving treatment outcomes.

Purpose of the Study:

  • To investigate alterations in atrial electrophysiology in patients with chronic persistent AF.
  • To compare atrial electrophysiology between patients with and without AF.

Main Methods:

  • Measured atrial monophasic action potential duration and effective refractory periods in 13 AF patients and 8 controls.
  • Utilized low-energy endocardial cardioversion.
  • Recorded data at the right atrial appendage and midlateral right atrial wall at various drive cycle lengths (600 ms, 400 ms).

Main Results:

  • Controls exhibited significantly longer effective refractory periods at the atrial appendage compared to the lateral wall.
  • AF patients showed shorter monophasic action potentials and effective refractory periods at both sites versus controls.
  • Effective refractory period dispersion was significantly greater in controls than in AF patients.

Conclusions:

  • The normal pattern of longer refractory periods at the right atrial appendage is lost in chronic persistent AF.
  • Marked shortening of the effective refractory period at the right atrial appendage in AF patients may explain high recurrence rates post-cardioversion.
Abstract

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