Deformational dynamics of the aortic root in elderly patients after aortic valve replacement with biological prostheses

Aim. The study was designed to comparatively assess dynamic changes of the aortic root structures depending on a phase of the cardiac cycle in patients with degenerative aortic stenosis, who underwent aortic valve replacement with different types of biological prostheses. Methods. This prospective parallel controlled randomized trial study was performed at Meshalkin National Medical Research Center over a period from 2011 to 2015. The inclusion criteria were severe aortic stenosis and patients’ age older than 65 years. 114 patients were randomized 1:1 in two groups: group I included 57 patients with stentless biological prostheses, while group II (control one) consisted of 57 patients with stented xenopericardial prostheses. The average age was 71 [66; 74] and 72 [69; 77] for the first and second groups, respectively (p = 0.054). All patients underwent aortic valve replacement. The operation was performed under standard normothermic cardiopulmonary bypass. The diameter of the implanted prostheses was 25 mm [24; 26] and 23 mm [21; 23] for the first and second groups, respectively (p = 0.375). An ECG-synchronized CT study of the aortic root was carried out in the postoperative period. Results. An intergroup systolic/diastolic difference in the values of the cross-sectional area of the aortic root at all levels was observed in patients with stentless bioprostheses, while the control group patients (with stented bioprostheses) had no such difference at the levels of the left ventricle output tract and the fibrous ring of the aortic valve. Conclusion. A stentless design of bioprostheses retains the deformational and elastic properties of the aortic root in elderly patients with aortic valve stenosis after surgical treatment.