Association of Left Atrial Appendage Morphology and Function With Stroke and Transient Ischemic Attack in Atrial

Judit Simon1, Jeff M Smit2, Mohammed El Mahdiui2

  • 1MTA-SE Cardiovascular Imaging Research Group, Medical Imaging Centre, Budapest, Hungary.

Insights

In atrial fibrillation patients, reduced left atrial appendage function and a swan shape increase stroke risk. The windsock shape, however, is protective against stroke/TIA.

Area of Science:

  • Cardiology
  • Medical Imaging
  • Stroke Prevention

Background:

  • Atrial fibrillation (AF) is a common arrhythmia associated with an increased risk of stroke.
  • The left atrial appendage (LAA) is a primary source of thrombus formation in AF patients.
  • Understanding LAA structure and function is crucial for stratifying stroke risk.

Purpose of the Study:

  • To investigate the correlation between left atrial appendage (LAA) morphology and function with the incidence of stroke/transient ischemic attack (TIA) in patients with AF.
  • To identify specific LAA shapes and functional parameters associated with a higher risk of thromboembolic events.

Main Methods:

  • Analysis of data from 649 AF patients undergoing catheter ablation.
  • Cardiac computed tomography (CT) and transesophageal echocardiography (TEE) were used to assess LAA morphology and function.
  • LAA morphologies were categorized into four distinct shapes: cauliflower, chicken wing, swan, and windsock.

Main Results:

  • Reduced LAA flow velocity (≤35.3 cm/s) was independently associated with a higher risk of stroke/TIA (OR 2.18).
  • The 'swan' LAA shape was also independently linked to an increased stroke/TIA risk (OR 2.69).
  • The 'windsock' LAA morphology demonstrated a protective effect against stroke/TIA (OR 0.32) compared to the 'cauliflower' shape, with significantly smaller LAA orifice area and volume.

Conclusions:

  • Reduced LAA function and 'swan' LAA morphology are independent predictors of increased stroke/TIA prevalence in AF patients.
  • The 'windsock' LAA morphology appears to be protective against stroke/TIA in this population.
  • LAA morphology, particularly the 'windsock' shape, influences LAA dimensions and may play a role in stroke risk stratification.