Hemodynamics of proximal coronary lesions in patients undergoing transcatheter aortic valve implantation: Patient-specific in silico study

Abstract

Aortic stenosis (AS) is a prevalent disease with significant implications for patients' prognosis, particularly when accompanied by coronary artery disease. However, the optimal revascularization strategy remains uncertain, especially with the emergence of transcatheter valve implantation (TAVI). In this study, we aimed to investigate the hemodynamics of proximal coronary lesions in the context of AS and their response to aortic valve replacement (AVR) using computational fluid dynamics (CFD) based on patient-specific data. Patient-specific CT scans and invasive coronary angiograms were utilized to create 3D models of the coronary arteries and aortic valve, enabling CFD simulations to provide pressure, flow, and shear stress data. The results demonstrated excellent agreement between CFD-estimated fractional flow reserve (FFR) and invasive measurements, affirming the accuracy of CFD methods.No noticeable variation of iFR (0.901 vs. 0.901, p = 0.89), CFR (1.97 vs. 1.98,p=0.49) nor FFR (0.805 vs. 0.804, p=0.81) values post-procedure were found. Additionally, AVR led to a reduction in the areas of coronary arteries exposed to high shear stress. These findings suggest that a post TAVI revascularization approach to non-critical proximal lesions (<70\%) may be deemed safe. This study underscores the potential benefits of CFD in preoperative planning for patients with AS and concomitant coronary artery disease, offering valuable insights into coronary physiology and the hemodynamic impact of TAVI.