CFD analysis of different arterial cannulation site during Heart Surgery with Cardiopulmonary Bypass

To assess, using a patient-specific computational fluid dynamics (CFD) analysis, hemodynamic characteristics of four different arterial cannulation sites routinely used during cardiopulmonary bypass (CPB). The arterial cannula was a standard 22 Fr diameter rigid cannula with a straight tip. A 3D real aorta model was generated from CT images using segmentation and reverse engineering techniques. The 22 Fr cannula was modeled and inserted at four common cannulation sites along the aortic vessel perpendicular to it. Each cannulation site was assigned to a clinical case-scenario characterized by the location of the arterial cannulation site: case 1, in the ascending aorta, 2 cm above the ST junction; case 2, in the aortic arc between the origin of the first two epi-aortic vessels (EAV) i.e brachiocephalic trunk and left common carotid artery; case 3, in the right subclavian artery; case 4, in the right common femoral artery. The assumption of identical boundary conditions was chosen for all simulations in order to enhance the only effects of arterial cannulation site onto blood flow distribution and Shear Stress indexes over the aortic vessel and its major branches. The flow was delivered through the cannula assuming the ascending aorta below the cannulation site was cross-clamped, as during open heart surgery.