Interatrial block and its association with an increased risk of ischemic stroke: A systematic review and meta-analysis.

Introduction: Several studies have suggested the association between interatrial block (IAB) and ischemic stroke. As no prior collective study has been discerned in this issue, we hence conducted systemic review and meta-analysis to assess the relationship between IAB and ischemic stroke.
Methods: We comprehensively searched the databases of MEDLINE, EMBASE, PUBMED, and the Cochrane from inception to January 2020. Included studies were published observational studies that compared the risk of ischemic stroke among patients with and without IAB. Data from each study were combined using the random-effects, generic inverse variance method of DerSimonian and Laird to calculate risk ratios and 95% confidence intervals (CIs). Subgroup analyses and meta-regression were performed to explore heterogeneity.
Results: Ten studies were included in this analysis, involving total 177,249 participants. Our study demonstrated no association between partial IAB and an increased risk of ischemic stroke with OR 1.19 (95% CI 0.99-1.43 p = 0.054),but a statistical correlation with an increased risk of stroke with OR 1.85 (95% CI 1.37-2.50, p < 0.001) in advanced IAB. Interestingly, our subgroup analysis of patients with prior stroke suggested higher risk of recurrent stroke in both advanced IAB (OR 4.73) and partial IAB (OR 1.65). Meta-regression suggested a history of stroke as an effect modifier in the interplay between IAB and risk of recurrent stroke.
Conclusion: Only advanced IAB is associated with an increased risk of stroke. However, further studies are warranted to further support this finding to confirm its clinical feasibility in stroke risk stratification.
Competing Interests: Declaration of competing interest None.
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