Natural history observations in moderate aortic stenosis

Background The natural history of patients with moderate aortic stenosis (AS) is poorly understood. We aimed to determine the long-term outcomes of patients with moderate AS. Methods We examined patients with moderate AS defined by echocardiography in our healthcare system, and performed survival analyses for occurrence of death, heart failure (HF) hospitalization, and progression of AS, with accounting for symptoms, left ventricular dysfunction, and comorbidities. Results We examined 729 patients with moderate AS (median age, 76 years; 59.9 % men) with a median follow-up of 5.0 years (interquartile range: 2.0 to 8.1 years). The 5-year overall survival was 52.3 % (95 % confidence interval [CI]: 48.6 % to 56.0 %) and survival free of death or HF hospitalization was 43.2 % (95 % CI: 39.5 % to 46.9 %). Worse New York Heart Association (NYHA) functional class was associated with poor long-term survival, with mortality rates ranging from 7.9 % (95 % CI: 6.6-9.2 %) to 25.2 % (95 % CI: 20.2-30.3 %) per year. Among patients with minimal or no symptoms, no futility markers, and preserved left ventricular function, 5-year overall survival was 71.9 % (95 % CI: 66.4-77.4 %) and survival free of death or HF hospitalization was 61.4 % (95 % CI: 55.5-67.3 %). Risk factors associated with adverse events were age, NYHA class, low ejection fraction and high aortic valve velocity (all p < 0.05). Conclusions Patients with moderate AS are at significant risk of death. Our findings highlight the need for more study into appropriate therapeutic interventions to improve the prognosis of these patients.