The Left Atrial Septal Pouch: A New Stroke Risk Factor?

Area of Science:

• Cardiology
• Neurology
• Medical Imaging

Background:

• The left atrial septal pouch (LASP) is an anatomical variation resulting from incomplete fusion of the atrial septa.
• LASP has been implicated as a potential source of thromboembolism, particularly in cryptogenic stroke.
• Previous research suggested a higher prevalence of LASP in patients experiencing cryptogenic strokes.

Purpose of the Study:

• To validate the association between LASP and cryptogenic stroke in a larger patient cohort.
• To compare the prevalence of LASP in stroke patients versus non-stroke patients.
• To investigate LASP as a potential risk factor for thromboembolic events.

Main Methods:

• A retrospective analysis of transesophageal echocardiograms (TEEs) performed between July 2011 and December 2018.
• Patients were categorized into 'stroke' (ischemic stroke or transient ischemic attack) and 'non-stroke' groups.
• LASP prevalence was determined and compared between groups, with stroke subtyping using TOAST criteria.

Main Results:

• The overall prevalence of LASP was 31% across all patients.
• LASP prevalence was significantly higher in patients with cryptogenic stroke (43%) compared to non-cryptogenic stroke patients (25%).
• A statistically significant association (p=0.02) was found between LASP and cryptogenic stroke.

Conclusions:

• The findings confirm a significant association between LASP and the risk of cryptogenic stroke.
• LASP may act as a thromboembolic nidus, contributing to stroke events.
• Further research is warranted to confirm generalizability and explore therapeutic implications of LASP as a stroke risk factor.