Abstract Body: Background: Left ventricular (LV) injury is a cardioembolic etiology of ischemic stroke. We aimed to 1) evaluate recurrent stroke risk among patients with cryptogenic stroke and LV injury, and 2) determine if there is a treatment effect with anticoagulation in this population.
Methods: We analyzed the multicenter, retrospective Cardiac Abnormalities in Stroke Prevention and Recurrence cohort of patients with cryptogenic ischemic stroke. The exposure was LV injury defined by 1) LV ejection fraction (EF) 20-40% and/or 2) LV wall motion abnormality (hypokinesis or akinesis). The primary composite outcome included recurrent stroke, major bleeding, or death. Cox proportional hazard models were built and sequentially adjusted for 1) age and sex (Model 1), and 2) age, sex, race, ethnicity, anti-thrombotic use, and vascular risk factors (Model 2). We then assessed if there was heterogeneity in treatment effect by LV injury status with an interaction term of LV injury and oral anticoagulation use in Model 2.
Results: Of 2,641 patients in CASPR, the analytic cohort included 2,191 patients with complete exposure and outcome data (median age 65 years, 49.8% female, median follow-up 1.55 years). There were 113 (5.2%) patients with LV injury (median LVEF 30%, interquartile range 25-34%). There were 559 incident events (321 recurrent strokes [288 ischemic], 71 major hemorrhages, 250 deaths). Among patients with LV injury, 15.9% were prescribed an anticoagulant within 7 days of index stroke (vs 9.6% without LV injury, p=0.03). The unadjusted risk of the primary outcome was non-significantly higher among patients with LV injury vs without (HR 1.40; 95% confidence interval [CI], 0.98-2.00), but became significant in Model 1 (HR 1.50; 95% CI, 1.21-1.85) and in Model 2 (HR 1.35, 95% CI, 1.11-1.64). In the LV injury subgroup, anticoagulation vs antiplatelet therapy was associated with a significant reduction in the primary outcome (HR 0.63, 95% CI, 0.43-0.94). In patients without LV injury, anticoagulation was associated with a higher risk of the composite outcome (HR 4.35, 95% CI, 1.69-11.16, p[interaction]=0.002).
Conclusion: In this observational study, there was an increased risk of the primary outcome which included recurrent stroke among patients with cryptogenic stroke and LV injury. Anticoagulation use in LV injury is associated with a significant reduction in the risk of the primary outcome. These findings warrant confirmation in a dedicated randomized controlled trial.