Left atrial enlargement and 1-year cerebrovascular events in subjects without atrial fibrillation: A prospective cohort study

OBJECTIVES: Left atrial enlargement (LAE) is a cardiac structural abnormality linked to adverse cardiovascular events, including stroke. However, its independent prognostic role in patients without atrial fibrillation (AF) remains unclear. DESIGN: prospective cohort study. SETTING: three teaching hospitals in Milan, Italy. PARTICIPANTS: consecutive adults undergoing transthoracic echocardiography (TTE) between 2012 and 2023. Patients with a history of AF or receiving anticoagulant therapy (for any indication) were excluded. INTERVENTIONS: participants underwent TTE in the context of standard clinical practice. MAIN OUTCOME MEASURES: LAE was categorized by left atrial volume index (LAVi) as absent (≤34 mL/m²), mild (>34 and ≤41 mL/m²), moderate (>41 and ≤48 mL/m²), or severe (>48 mL/m²). The primary outcome was a composite of cerebrovascular events (CVEs), including ischemic stroke or transient ischemic attack (TIA), within 1 year of the index echocardiogram. Multivariate logistic regression models were used to evaluate the independent association of LAE with 1-year CVEs. RESULTS: We included 53,109 subjects with a median age of 66 years (48 % female). CVEs occurred in 1318 subjects (2.5 %). In the multivariate analysis, all categories of LAE were associated with 1-year CVEs compared with no LAE (mild: OR 1.21, 95 % CI 1.03 to 1.43; moderate: OR 1.48, 95 % CI 1.20 to 1.83; severe: OR 1.85, 95 % CI 1.54 to 2.22). This association was independent of other relevant predictors. CONCLUSIONS: LAE defined by LAVi is associated with 1-year CVEs in subjects without known AF and ongoing anticoagulation, suggesting that LAVi can serve as a marker to refine CVE risk stratification.