Aortic stenosis: even mild disease is significant.

The spectrum of calcific aortic valve disease ranges from aortic sclerosis, without obstruction to ventricular outflow, to severe aortic stenosis. The natural history of symptomatic and asymptomatic severe aortic valve stenosis has been evaluated by Doppler echocardiography in several retrospective and prospective studies. In addition, there is substantial data on the rate of haemodynamic progression of aortic stenosis of all degrees of severity. However, there is much less data on clinical outcomes in adults with asymptomatic mild-moderate stenosis. Knowledge of the expected outcomes with mild aortic valve disease is especially important given that aortic sclerosis is present in about 25% of adults over age 65 years and progression to aortic stenosis occurs within 7 years in 16% of patients with aortic sclerosis. In this issue of the European Heart Journal, Rosenhek and colleagues provide an important contribution to our understanding of the natural history of mild to moderate aortic stenosis This consecutive cohort of 176 initially asymptomatic adults was identified over a 1-year period, with detailed clinical outcomes ascertained over an average of 4 years. Although earlier studies based on patient groups identified at catheterization suggested a relatively benign prognosis, the findings in the current study extend the observations from the Seattle aortic stenosis study that both adverse clinical outcomes and progression to severe aortic stenosis occur at a very high rate in adults with mild-moderate aortic stenosis (Table 1).