Comparison of the Graft Angles Effects on the Temporal Wall Shear Stress Gradients in the Aorto-Coronary and Coronary-Coronary Bypasses

Abstract

In this theoretical study, the effect of various types of bypass graft angles on the flow field, has been investigated specially on the temporal Wall Shear Stress (WSS) on the toe, heel and some locations on the bed of the Left Anterior Descending (LAD) artery at the anastomoses areas in the Aorto-Coronary (AC) and Coronary-Coronary (CC) bypasses. Flow fields in both bypasses with angles of 20º, 30º and 40º by 75% stenosis were simulated using Fluent software. The results show high restenosis potential in the side-to-end anastomosis, heel and host artery bed in the CC bypass, and also high restenosis potential at end-to-side in comparing of the AC bypass. Effects of variable graft angles on the WSS on the upper and lower heels in the CC bypass were negligible and the length of the bed influenced by variation of the graft angle was restricted to one diameter distal to the toe in AC bypass and one diameter distal to the lower toe in the CC bypass and finally use of graft angles near 30º was of other important results.

Keywords

• wall shear stress
• coronary bypass
• anastomosis and graft angle