Asymptomatic aortic stenosis: when to operate?

Although there is general agreement that symptomatic aortic stenosis (AS) requires urgent surgery, it remains controversial when to operate on asymptomatic but nevertheless severe AS. Current practice guidelines recommend valve replacement in patients in asymptomatic when the systolic left ventricular function is found to be reduced without other explanation. Otherwise, surgery should be or at least may be considered (recommendation classes IIa or IIb) in asymptomatic patients with severe AS and an abnormal exercise test, a high likelihood of rapid progression, or very severe AS in the presence of low surgical risk. This article reviews recent publications evaluating early elective surgery versus watchful waiting as recommended by current guidelines. The second focus of this review is on new insights on predictors of outcome in asymptomatic AS that may improve timing of surgery and therefore deserve to be considered in future recommendations for the treatment of this difficult patient group.