Background: Aortic stenosis (AS) is becoming increasingly common with the aging population. Many of these patients have reduced left ventricular (LV) ejection fractions (EF) or low transvalvular gradients resulting in reluctance to offer aortic valve replacement (AVR).
Methods: Our echocardiographic database for the period of 1993 to 2003 was screened for severe AS (aortic valve area [AVA] </= 0.8 cm(2)) with LVEF 0.35 or less or a mean transvalvular gradient of 30 mm Hg or less. Chart reviews were performed for clinical, pharmacologic, and surgical details. Survival data were obtained from the Social Security Death Index and analysis was performed using Kaplan-Meier, Cox regression, sensitivity, and propensity score analysis.
Results: Of the 740 patients with severe AS, 194 (26%) had severe LV dysfunction defined as EF 0.35 or less and 168 (23%) a mean transvalvular gradient of 30 mm Hg or less. Low ejection fraction was not a prerequisite for a low gradient. The Univariate predictors of higher mortality in both groups included higher age, lower ejection fraction, renal insufficiency, and lack of aortic valve replacement. Lack of aortic valve replacement was a strong predictor of mortality after adjusting for 18 clinical, echocardiographic, and pharmacologic variables. There were 72 patients with EF 0.20 or less, of whom 18 had AVR, which was associated with a large survival benefit similar to the entire cohort. In the 52 patients with EF 0.55 or less and mean gradient less than 30 mm Hg, the 5-year survival with AVR was 90% compared with 20% without AVR (p < 0.0001) which was supported by propensity score analysis as well.
Conclusions: Severe LV dysfunction or a low transvalvular gradient is seen in about a quarter of patients with severe AS and there is a reluctance to offer AVR in these patients. Aortic valve replacement is associated with a large mortality benefit in these patients.