Comprehensive risk stratification of Japanese patients with aortic stenosis - A proposal of a new risk score from the CHART-2 study -

Background: The risk of patients with aortic stenosis (AS) should be stratified not only by AS severity but also by comorbidities. Methods and Results: We aimed to develop a risk score for mortality in 412 patients with AS (pressure gradient ≥30 mmHg, mean age 74.9 years, male 52.4%) in the CHART-2 Study (n=10,219). During a 3-year follow-up, 73 (17.7%) patients died. Crude 3-year mortality of patients in New York Heart Association (NYHA) classes I, II, and III/ IV was 9.5%, 16.5%, and 49.7%, respectively (P<0.001). Stepwise Cox regression analysis showed that the combination of 7 factors was the best model to predict the mortality of AS patients, who were scored according to their hazard ratios, including NYHA class III–IV (score 6), male sex (3), serum albumin level ≤4 g/dl (2), aortic peak flow ≥4.5 m/s (2), age ≥75 years (2), chronic kidney disease (2), and anemia (1). Receiver-operating characteristic analysis showed excellent association between the sum of the scores and 3-year mortality (area under the curve, 0.78). The multivariate Cox proportional hazard model demonstrated that the present risk score also well stratified the mortality risk. Conclusions: The present study demonstrates that, in addition to the classical prognostic factors related to symptoms and AS severity, various comorbidities are associated with mortality. Thus, the present comprehensive risk score may be useful for risk stratification of AS patients.