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Catheter Ablation in Combination With Left Atrial Appendage Closure for Atrial Fibrillation
28:13

Catheter Ablation in Combination With Left Atrial Appendage Closure for Atrial Fibrillation

Published on: February 26, 2013

Thrombus formation in the left atrial appendage in the course of atrial fibrillation

N Alessandri1, S Mariani, A Ciccaglioni

  • 1Dipartimento di Scienze Cardiovascolari e Respiratorie, University of Rome La Sapienza, Rome, Italy.

European Review for Medical and Pharmacological Sciences
|December 3, 2003
PubMed

Insights

Thromboembolism (TE) risk in atrial fibrillation patients can be better assessed using left atrial appendage flow duration. This new parameter, measured via transesophageal echocardiography, improves the reliability of TE risk evaluation.

Area of Science:

  • Cardiology
  • Medical Imaging
  • Vascular Medicine

Background:

  • Thromboembolism (TE) in nonvalvular atrial fibrillation often originates from the left atrial appendage.
  • Previous studies identified parameters like flow, ejection fraction, and volume for TE risk assessment.

Purpose of the Study:

  • To investigate novel echocardiographic parameters for evaluating thromboembolism risk in atrial fibrillation patients.
  • To assess the utility of left atrial appendage (LAA) flow duration as a predictor of TE.

Main Methods:

  • Transesophageal echocardiography was performed on 69 patients.
  • Patients were categorized into three groups: sinus rhythm (Gr.A), atrial fibrillation without thrombi (Gr.B), and atrial fibrillation with thrombi (Gr.C).
  • Key parameters measured included atrial volume, LAA ejection fraction, flow velocity, and LAA flow duration.

Main Results:

  • LAA volume was significantly larger in patients with atrial fibrillation (Gr.B and Gr.C) compared to sinus rhythm (Gr.A).
  • LAA ejection fraction was significantly reduced in patients with thrombi (Gr.C).
  • LAA flow duration, as a percentage of the cardiac cycle, was markedly reduced in patients with thrombi (21%) compared to those without (65%) and sinus rhythm patients (85%).

Conclusions:

  • Left atrial appendage flow duration, particularly its ratio to the cardiac cycle, represents a novel and reliable parameter for TE risk assessment.
  • This measurement, obtainable through transesophageal echocardiography, enhances the evaluation of TE risk beyond previously established parameters.
Abstract

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