Diagnostic capabilities of echocardiographic indicators of acceleration time and the ratio of acceleration time to total left ventricular ejection time in the assessment of severe aortic stenosis in patients with reduced left ventricular ejection fraction

Abstract

Objectives: 1) to evaluate the diagnostic capabilities of AT and AT/ET in determining severe AS in patients with reduced LV EF and low stroke volume.2) to determine the threshold values for AT and AT/ET in the diagnosis of severe AS in patients with low stroke volume and low transaortic gradient.Materials and methods. This is prospective single center study included 70 patients with low transaortic pressure gradient, reduced LV ejection fraction was and severe aortic stenosis. All patients have been examined from 2017 to 2022. Inclusion criteria for the study are: isolated AV stenosis with, reduced LV RF, low transaortic pressure gradient. Severity of AS was identified based on dobutamine stress echocardiography and aortic valve area (AVA). Severe stenosis was defined as AVA< 1 cm2.Result. A statistically significant and high negative correlation was found between the AVA and AT/ET ratio, (r = 0.77, p < 0.001) and weak correlation with the AT indicator (r = 0.41, p = 0.01). The RoC-analysis showed the greatest predictive ability in the differential diagnosis of severe AS for the ratio AT/ET (AUC = 0.84 ± 0.54, p < 0.001) and the lower predictive ability for the indicator AT (AUC = 0.63 ± 0.72, p < 0.02). The optimal threshold value for determining severe AS for the AT / ET > 0.32 (sensitivity of 92%, specificity of 70%), for AT > 99 (sensitivity of 81%, specificity of 88%). Multiple logistic regression analysis revealed that the AT/ET ratio is the only echocardiographic parameter that has a significant impact on the differential diagnosis of severe AS in patients with reduced LV EF (OR 1.5; 95% CI 1.2–1.9, p = 0.001). There was low interobserver variability in measurements of AT score (intraclass correlation coefficient was 0.93 [95% CI, 0.80-0.97] and AT/ET ratio (intraclass correlation coefficient was 0.88 [95% CI, 0.75–0.95]).Conclusions.In patients with AS and reduced LV stroke volume the AT/ET ratio is highly sensitive and well reproducible in the diagnosis of severe AS. The AT index has a weak diagnostic ability of severe AS in that patients.The threshold value of AT/ET >0.32 can diagnose severe AS with a high degree of probability in patients with reduced LV stroke volume and reduced transaortic gradients with reduced LV EF.