Abstract Background Left atrial strain (LAS) has been widely studied as predictor of atrial fibrillation (AF) after cryptogenic stroke (CS). However, the evidence about its prognostic role in terms of stroke recurrence and death in this setting remains scarce. Methods From April 2019 to April 2022, 92 consecutive patients with ischemic stroke or transient ischemic attack with ABCD2 scale ≥4 of unknown etiology were prospectively recruited. Echocardiography, including LAS was performed during admission. The primary outcome was the composite of stroke recurrence or death. Results Mean age was 77.5±7.7 and 58% of patient were female. After a median follow up of 28 months, the primary outcome measure occurred in 15 patients (16%). The primary outcome was more frequent in patients with diabetes (53% vs 21%; p=0.02), chronic kidney disease (33% vs 10%; p=0.034) and history of heart failure (13% vs 0%; p=0.025). LAS reservoir (LASr) and LAS conduct (LAScd) were lower in patients developing the primary outcome (21±7 vs 28.8±11%; p=0.017 and 7.7±3.9 vs 13.7±7%; p=0.007, respectively). On multivariate analysis, diabetes (HR 7.4, 95%CI 1.2-47; p=0.034)), LASr (HR 0.2, 95%CI 0.05-0.8; p=0.023), LAScd (HR 0.17, 95%CI 0.04-0.7; p=0.013) and LAS contraction (HR 0.2, 95%CI 0-05-0.8; p=0.025) were independent predictors of stroke recurrence or all-cause death after CS (Table). On long-rank test (using the discriminatory cut-off values of LASr <23% and LAScd <10%), LASr (p=0.009) (Figure 1) and LAScd (p=0.016) were associated with higher risk of the primary outcome. Conclusion Lower values of LAS reservoir, conduct and contraction are independently associated with higher risk of stroke recurrence or death after CS