Anatomical features and hemodynamic aspects of vascular anastomoses in reconstructive cardiovascular surgery

Objective. To determine the anatomically optimal configuration and hemodynamic parameters of various types of vascular anastomoses by numerical simulation to ensure long-term patency. Material and methods. Numerical modeling of blood flow in three types of anastomoses was performed: end-to-end, end-to-side at 35°, and end-to-side at 90°. The Navier-Stokes equations for an incompressible fluid in their standard form were used. The finite element mesh size was 2 mm. Velocity fields, the presence of recirculation zones, and turbulence were assessed. Results. The end-to-end anastomosis demonstrated no recirculation zones. The Reynolds number was 9500, with no large-scale vortex structures detected. The 35° and 90° end-to-side anastomoses showed significant zones of turbulence and blood recirculation, most significant at the 90° angle, where large-scale vortices form, capable of reducing distal blood flow. Conclusion. From an anatomical and hemodynamic perspective, the end-to-end anastomosis is the most physiological, ensuring favorable flow patterns and minimal impact on blood cells. The end-to-side configuration requires a strictly individualized approach, taking into account the anastomotic angle and the type of vascular graft.