Left Atrial Septal Pouch (LASP) and cryptogenic stroke risk: An updated systematic review and meta-analysis of observational studies.

Background: The left atrial septal pouch (LASP) is a small anatomical septal recess in the heart that has been linked with cardioembolic events. A systematic appraisal of the existing literature is necessary to establish a better understanding of the risk as studies continue to indicate a correlation between LASPs and cryptogenic strokes.

Objectives: To determine the level of association between the presence of LASP and the risk of developing cryptogenic stroke.

Methods: We searched PubMed, EMBASE and Scopus for studies comparing the prevalence of LASP in patients with cryptogenic stroke against non-cryptogenic stroke control groups from inception till December, 2023. The Newcastle Ottawa scale was used for quality assessment and Comprehensive Meta-Analysis Version 3.3 was used for data analysis with odds ratio (OR) as the effect measure.

Results: Our review included a total of 10 retrospective, observational studies published between 2010 to 2022. A total of 683 cases of cryptogenic strokes were identified, out of which 33.1 % (n = 271) were associated with a LASP. Among the non-cryptogenic stroke controls (n = 2641), LASP was present in 20.6 % cases (n = 476). The aggregate OR for cryptogenic stroke was 1.618 times greater than non-cryptogenic stroke (p < 0.001) among LASP cases, CONCLUSION: The presence of a septal pouch in the left atrium is significantly linked to a higher risk of developing cryptogenic strokes. As a potential site of thrombus formation and subsequent dislodgement, further large-scale studies are necessary to establish the guidelines for management and prophylaxis to prevent embolic events.