Does the presence of moderate or severe aortic stenosis increase the risk of long-term mortality compared to no aortic stenosis?
Moderate aortic stenosis is associated with a markedly increased risk of long-term mortality (43% at 5 years), challenging the traditional paradigm that only severe aortic stenosis carries a poor prognosis when untreated.
BACKGROUND Historical data suggesting poor survival without treatment is largely confined to severe aortic stenosis (AS). OBJECTIVES To determine the prognostic impact of all levels of native valvular AS. METHODS Severity of AS was characterized by convention and by statistical distribution in 122,809 males (61±17 years) and 118,494 females (62±19 years), with measured Aortic Valve (AV) mean gradient, peak velocity and/or area. The relationship between AS severity and survival were then examined during median 1,198 (IQR 591, 2,166) days of follow-up. Patients with previous aortic valve intervention were excluded. RESULTS Overall, 16,129 (6.7%), 3,315 (1.4%) and 6,383 (2.6%) cases had mild, moderate and severe AS, respectively. On an adjusted basis (versus no AS - 5-year mortality 19%), patients with mild-to-severe AS had an increasing risk of long-term mortality (adjusted hazard ratio 1.44 to 2.09; p50%) and cardiovascular disease was evident from a mean AV gradient >20.0 mmHg (moderate AS) after adjusting for age, sex, left ventricular systolic, diastolic dysfunction, and aortic regurgitation. CONCLUSIONS These unique data confirm that when left untreated, severe AS is associated with poor long-term survival. Moreover, they also suggest poor survival rates in patients with moderate AS.
“We have shown for the first time, in the largest study of aortic stenosis ever undertaken, that aortic stenosis is not a benign disease throughout the spectrum of severity. The current 'watchful waiting' approach to non-severe aortic stenosis mandates serious consideration. Patients in the moderate group of our study had very similar 5-year mortality outcomes to the severe group.”
Strange et al. (2019) studied this question.