A comparison of the diagnostic capabilities of the ratio of acceleration time to total left ventricular ejection time (AT/ET) in determining the severity of aortic stenosis in patients with bicuspid and tricuspid aortic valve: retrospective comparative study

Objective. We aimed to compare the diagnostic capabilities of the ratio of acceleration time to total left ventricular ejection time (AT/ET) in determining the severity of aortic stenosis (AS) in patients with bicuspid and tricuspid aortic valves (AV).

Material and methods. We retrospectively analyzed the data of 187 patients with moderate and severe AS who underwent diagnostic examination at the Penza Federal Center for Cardiovascular Surgery. The patients were divided into 2 groups based on whether their AV was tricuspid or bicuspid. Visual assessment of the AV structure was performed using transthoracic echocardiography (TTE). In indeterminate cases, computed tomography was used for the assessment.

Results. A comparative analysis of the echocardiographic characteristics of patients with tricuspid and bicuspid AV did not reveal a statistically significant difference between the patient groups (p ≤0.05). Linear regression analysis in patients with a tricuspid AV demonstrated a statistically significant correlation between AT/ET scores and peak gradient (G_max) (r=0.68, р=0.03), mean gradient (G_mean) (r=0.78, р=0.01), effective orifice area (EOA) (r=0.7, р=0.03), and doppler velocity index (DVI) scores (r=0.72, р=0.02). In patients with a bicuspid AV, a similarly significant correlation was found between the AT/ET index and G_max (r=0.67, р=0.02), G_mean (r=0.8, р <0.001), EOA (r=0.72, р=0.04), and DVI (r=0.75, р=0.01). The receiver operating characteristic analysis demonstrated a high predictive ability of AT/ET for severe aortic valve stenosis (with a value >0.35). The area under the curve in patients with tricuspid and bicuspid AV was 84 (p <0.001) and 86 (p <0.001), respectively. For determining severe AV stenosis in patients with a tricuspid AV, the sensitivity and specificity of AT/ET >0.35 was 84% and 75%, respectively; and in patients with a bicuspid AV, it was 87% and 78%, respectively.

Conclusion. The AT/ET ratio has comparable diagnostic capabilities in determining severe AS in patients with tricuspid and bicuspid AV structures. The AT/ET >0.35 is a highly sensitive parameter for defining severe AS for both morphologies of AV.