Changes in left ventricular function and geometry after aortic valve replacement in patients with severe aortic stenosis

Abstract

Background: This study aims to evaluate the effects of different types and sizes of prostheses on the left ventricular function and geometry after aortic valve replacement (AVR) in patients with severe aortic stenosis. Methods: Eighty-five patients with severe aortic stenosis were studied in three groups [Group 1, mechanical AVR (n=31); Group 2, stentless biological AVR (n=34); Group 3, stented biological AVR (n=20)]. Left ventricular geometry and function were assessed by transthoracic echocardiography preoperatively and at six months after AVR. Primary endpoint of the study was the change in the left ventricular mass index (LVMI) at six months while secondary endpoints were the New York Heart Association (NYHA) functional class, transvalvular gradients, aortic valve space, left ventricular ejection fraction (LVEF) and diameters, septal thickness and indexed effective orifice area (IEOA). Results: A significant improvement in the NYHA functional class was seen in all groups at six months. Based on the echocardiographic evaluations at six months, there were no significant differences among the groups in terms of ΔLVEF (p=0.52), ΔLVEDD (p=0.24), ΔLVESD (p=0.86), Δseptal thickness (p=0.25). Indexed effective orifice area was significantly higher in stentless group, compared to the other groups (p=0.002). ΔLVMI was significantly greater in mechanical and stentless biological valves, compared to the stented biological AVR (p=0.042). When the patients with annulus size smaller than 25 mm were evaluated, it was shown that ΔLVMI was further decreased in stentless biological AVR, compared to the other groups (p=0.029). Conclusion: Although implantation of stentless biological AVR requires longer ischemic times, regression in the LVMI is more prominent in stented biological valves, particularly in patients with small aortic root.