Prognostic Significance of Atrial Cardiopathy in Patients with Embolic Stroke of an Undetermined Source

AIM: Atrial cardiomyopathy (AC) is associated with cardiovascular events, but the benefit of anticoagulation in embolic stroke of an undetermined source (ESUS) remains unclear. We aimed to prospectively evaluate the prognostic value of AC in patients with ESUS. METHODS: We prospectively enrolled patients with ESUS who were hospitalized within 7 days of onset (January 2019 - December 2021). AC was defined as an N-terminal pro-B-type natriuretic peptide level ＞250 pg/ml, P-wave terminal force in lead V1 ＞5000 µV·ms, or enlarged left atrial diameter. Ischemic stroke/transient ischemic attack (TIA) recurrence was evaluated using Fine-Gray sub-distribution hazard models with death as a competing event. Cox proportional hazards models were used for supportive analyses and all-cause mortality. RESULTS: Among the 345 patients (mean age 59.22±13.19 years; 69.0% men), 42.0% met the criteria for AC. During a median follow-up of 18.1 months, 36 patients experienced ischemic stroke, 2 had TIA, and 18 died. AC was strongly associated with ischemic stroke/TIA recurrence in competing risk analyses (adjusted subdistribution hazard ratio [aSHR] 3.36, 95% CI 1.65-6.86; P＜0.001). For all-cause mortality, AC was associated with a higher risk after adjusting for age and sex (adjusted hazard ratio 3.80, 95% CI 1.19-12.08; P = 0.024). Adding AC to conventional risk models significantly improved the NRI (ischemic stroke/transient ischemic attack: 72.45%, P＜0.001; mortality: 66.16%, P = 0.002) and IDI (4.52%, P＜0.001; 3.89%, P = 0.041). CONCLUSIONS: AC independently predicts recurrent ischemic stroke/TIA in ESUS and improves risk stratification, while its association with mortality requires cautious interpretation due to limited events.