Prognostic Risk Stratification of Patients with Moderate Aortic Stenosis

Background: Currently risk stratification of moderate aortic stenosis (AS) is still incipient. The aim of this study was to identify prognostic factors in patients with moderate AS. Methods: The prognosis of patients with moderate AS (1 < aortic valve area <= 1.5 cm(2)) stratified by left ventricular ejection fraction (LVEF; 50%), stroke volume index (SVI; 35 mL/m(2)), and elevated E/e' ratio (average, 14) was compared with that of the age- and sex-matched general population. Results: Of 696 patients (median age, 77 years; aortic valve area 1.3 cm(2); 57% men), 279 (40%) died during a median follow-up period of 3.4 years. Mortality was higher in patients with moderate AS than reference (mortality ratio, 2.43; 95% CI, 2.17-2.72). LVEF < 50%, SVI < 35 mL/m(2), and elevated E/e' ratio were present in 113 (17%), 54 (8%), and 330 (54%) patients; mortality ratios were 3.89 (95% CI, 3.07-4.85), 6.40 (95% CI, 4.57-8.71), and 2.58 (95% CI, 2.21-3.00), respectively. Even if LVEF or SVI was preserved, the mortality ratio was more than twice than reference (P<.001), but elevated E/e' ratio could discriminate additional patients at higher risk (hazard ratio [HR], 2.71; 95% CI, 1.88-3.91). Two hundred one patients (29%) underwent aortic valve replacement at a median of 2.3 years after the diagnosis of moderate AS. LVEF < 50% (HR, 2.98; 95% CI, 1.39-6.56), SVI < 35 mL/m(2) (HR, 3.34; 95% CI, 1.02-10.90) and elevated E/e' ratio (HR, 2.73; 95% CI, 1.26-5.94) were all associated with worse prognosis even if aortic valve replacement was performed. Conclusions: In patients with moderate AS, those with decreased LVEF and/or SVI are at high risk. Even if these parameters are preserved, patients with elevated E/e' ratios are at intermediate risk. Further investigation is warranted to assess whether earlier intervention could improve outcomes and reduced cardiac-related death among patients at high and intermediate risk.