Relationship Between the Ratio of Acceleration Time/Ejection Time and Mortality in Patients With High-Gradient Severe Aortic Stenosis.

Background The ratio of acceleration time/ejection time (AT/ET) is a simple and reproducible echocardiographic parameter that integrates aortic stenosis severity and its consequences on the left ventricle. No study has specifically assessed the prognostic impact of AT/ET on outcome in patients with high-gradient severe aortic stenosis (SAS) and no or mild symptoms. We sought to evaluate the relationship between AT/ET and mortality and determine the best predictive AT/ET cutoff value in these patients. Methods and Results A total of 353 patients (median age, 79 years; 46% women) with high-gradient (mean pressure gradient ≥40 mm Hg and/or aortic peak jet velocity ≥4 m/s) SAS, left ventricular ejection fraction ≥50%, and no or mild symptoms were studied. The impact of AT/ET ≤0.35 or >0.35 on all-cause mortality was retrospectively studied. During a median follow-up of 39 (25th-75th percentile, 23-62) months, 70 patients died. AT/ET >0.35 was associated with a considerable increased mortality risk after adjustment for established prognostic factors in SAS under medical and/or surgical management (adjusted hazard ratio [HR], 2.54; 95% CI, 1.47-4.37; P<0.001) or conservative management (adjusted HR, 3.29; 95% CI, 1.70-6.39; P<0.001). Moreover, AT/ET >0.35 improved the predictive performance of models including established risk factors in SAS with better global model fit, reclassification, and discrimination. After propensity matching, increased mortality risk persisted when AT/ET >0.35 (adjusted HR, 2.10; 95% CI, 1.12-3.90; P<0.001). Conclusions AT/ET >0.35 is a strong predictor of outcome in patients with SAS and no or only mild symptoms and identifies a subgroup of patients at higher risk of death who may derive benefit from earlier aortic valve replacement.

Clinical Significance of Ejection Dynamics Parameters in Patients with Aortic Stenosis: An Outcome Study.

BACKGROUND: Ejection dynamics parameters are useful in assessing prosthetic valve obstruction, but very limited data are available in the setting of native aortic stenosis (AS). The aim of this study was to evaluate and compare the prognostic value of acceleration time (AT) and the ratio of AT to ejection time (ET) in patients with AS. METHODS: AT and AT/ET were prospectively measured in 456 patients with AS (aortic valve area < 1.3 cm2; mean aortic valve area, 0.85 ± 0.24 cm2). The relationships between AT/ET, AT, and mortality during follow-up were studied. RESULTS: During a median follow-up period of 35 months (interquartile range, 33-37 months), 124 patients died. After adjustment for variables of prognostic importance, including mean pressure gradient, stroke volume index, and aortic valve replacement as a time-dependent covariate, patients in the highest tertiles of both AT/ET (>0.36) and AT (>112 msec) were at high risk for overall mortality (adjusted hazard ratios, 2.44 [95% CI, 1.46-4.08; P = .001] and 1.78 [95% CI, 1.06-2.98; P = .029], respectively) compared with those in the lowest tertiles of AT/ET and AT, while survival was similar for the other tertiles (P = NS for all). Compared with patients with AT/ET ≤ 0.36, an increased risk for overall mortality was observed in patients with AT/ET > 0.36 (adjusted hazard ratio, 2.51; 95% CI, 1.66-3.78; P < .0001), while the risk for mortality was not significantly increased in patients with AT > 112 msec compared with those with AT ≤ 112 msec. Adding AT/ET > 0.36 to a multivariate model including classical variables of prognostic importance, including mean pressure gradient and stroke volume index, improved predictive performance in terms of overall mortality, with improved global model fit, reclassification, and better discrimination. CONCLUSIONS: Among ejection dynamics parameters in patients with AS, AT/ET is strongly associated with excess risk for death during follow-up. AT/ET should be considered in the multiparametric echocardiographic prognostic assessment of patients with AS in clinical practice.