Original Articles
Exercise stress echocardiography in patients with aortic stenosis: impact of baseline diastolic dysfunction and functional capacity on mortality and aortic valve replacement
Abstract
Background: Patients with aortic stenosis (AS) often undergo exercise echocardiography. Diastolic dysfunction (DD) is frequently associated with AS but little is known about its impact on functional capacity (FC). We sought to determine the relationship between DD and FC and their impact on mortality and need for aortic valve replacement (AVR) in patients with AS.
Methods and results: Data was analyzed for consecutive patients with any degree of AS undergoing exercise stress echocardiography between 2000 and 2010 at our institution. The primary endpoint was a composite of death or need for AVR. We identified 1,267 patients [mean age 67±11 years, ejection fraction (56±7)%, mean aortic valve gradient 19±12 mmHg, mean maximal metabolic equivalents (METs) achieved 8±2.6]. The proportion with normal, stage 1, and ≥ stage 2 diastology was 195 (15%), 928 (73%), 144 (12%). A total of 475 (37.5%) patients had a primary outcome with 164 deaths (mean follow up 5.6±4.1 years) and 341 AVR (mean follow up 2.4±2.6 years). Predictors of FC were age, gender, body mass index, Bruce protocol, heart rate recovery (HRR), ejection fraction, mean aortic valve gradient, and diabetes but not baseline DD. Baseline DD [HR 1.82, 95% CI (1.17, 2.82), P=0.008] and FC [HR 0.93, 95% CI (0.88, 0.98), P=0.003] were independent predictors of death or AVR.
Conclusions: For patients with AS undergoing exercise echocardiography, baseline DD was not predictive of FC. However, both baseline DD and FC were independent predictors of death or need for AVR.
Methods and results: Data was analyzed for consecutive patients with any degree of AS undergoing exercise stress echocardiography between 2000 and 2010 at our institution. The primary endpoint was a composite of death or need for AVR. We identified 1,267 patients [mean age 67±11 years, ejection fraction (56±7)%, mean aortic valve gradient 19±12 mmHg, mean maximal metabolic equivalents (METs) achieved 8±2.6]. The proportion with normal, stage 1, and ≥ stage 2 diastology was 195 (15%), 928 (73%), 144 (12%). A total of 475 (37.5%) patients had a primary outcome with 164 deaths (mean follow up 5.6±4.1 years) and 341 AVR (mean follow up 2.4±2.6 years). Predictors of FC were age, gender, body mass index, Bruce protocol, heart rate recovery (HRR), ejection fraction, mean aortic valve gradient, and diabetes but not baseline DD. Baseline DD [HR 1.82, 95% CI (1.17, 2.82), P=0.008] and FC [HR 0.93, 95% CI (0.88, 0.98), P=0.003] were independent predictors of death or AVR.
Conclusions: For patients with AS undergoing exercise echocardiography, baseline DD was not predictive of FC. However, both baseline DD and FC were independent predictors of death or need for AVR.
