Natural History Of Severe Aortic Stenosis With Preserved Ejection Fraction: Impact Of Transvalvular Gradients and Flow

Background: Recent studies have indicated that up to 30% of patients (pts) with severe aortic stenosis (SAS), defined as an indexed aortic valve area 40 mmHg) and indexed stroke volume (≤ ou > 35 ml/m2). The primary endpoint was all causes mortality. To evaluate natural history, pts undergoing surgery during follow–up were censored at the time of surgery (n=84). Results: 145 had HG SAS (45%) and 215 had LG SAS (55%). During a mean follow–up of 36 ± 28 months, 154 patients died. Cox analysis identified age, NYHA class, the presence of diabetes and chronic obstructive lung disease as independant predictor of death. In the subgroup of asymptomatic pts, the same analysis identified age, the presence of diabetes and mean transvalvular gradient as independent predictors of death. Kaplan Meier survival curves demonstrated that survival was better in pts with LG SAS than in those with HG SAS, both in the overall population (47 vs 31%, p<0.01) and in the asymptomatic subgroup (58 vs 35%, p