Left Atrial Strain Predicts Cardiac Outcomes in Moderate Aortic Stenosis

BACKGROUND: Moderate aortic stenosis (AS) poses a substantial risk for adverse outcomes, yet its prognostic determinants and cardiac remodeling markers remain underexplored. This study aimed to evaluate prognostic factors, including left atrial strain, and their predictive value for adverse cardiac events in patients with moderate AS. METHODS: A retrospective cohort study included 1125 patients diagnosed with moderate AS between 2008 and 2019. Cardiac remodeling indices, including left atrial reservoir strain (LARS) and left ventricular global longitudinal strain, were assessed using speckle-tracking echocardiography. The primary outcome was cardiac death, while the secondary outcome was a composite of cardiac death or heart failure hospitalization. RESULTS: Among the study population (median age, 74 years; 47.2% women), the Kaplan-Meier–estimated 5-year rates of cardiac mortality and the composite outcome were 16.7% and 33.9%, respectively, during a median follow-up of 42.8 months. Of the cardiac remodeling indices evaluated, LARS emerged as the most sensitive and independent predictor of cardiac death (adjusted hazard ratio, 0.948 per 1% increase; P =0.003) and the composite outcome (adjusted hazard ratio, 0.940 per 1% increase; P <0.001). Notably, the prognostic significance of reduced LARS persisted even after aortic valve replacement (hazard ratio, 2.177 for LARS <20.6% versus ≥20.6%; P =0.024). Furthermore, among all cardiac remodeling parameters analyzed, LARS showed the highest predictive performance for the composite outcome (C-index, 0.586 [95% CI, 0.541–0.632]) compared with other parameters. CONCLUSIONS: LARS is a sensitive and independent prognostic marker in moderate AS, reflecting cardiac remodeling. Regular assessment of left atrial strain could enhance risk stratification and guide clinical management strategies in patients with moderate AS.