[Physiological characteristics of arterial graft for coronary artery bypass surgery].

Arterial grafts have been used widely for coronary artery bypass grafting (CABG) because of their excellent long patency. However, some clinical reports suggest that blood flow in arterial grafts may not be adequate compared with aorto-coronary bypass grafting. Pressure in arterial grafts was measured in patients undergoing CABG. The pressure tracing in the ascending aorta (AA) was maintained during diastole. The systolic pressure wave in ITA and GEA was narrow, while the diastolic pressures fell rapidly: the diastolic pressure in GEA was lower than in ITA. The area under the pressure wave was measured in diastole and in systole. Although there was no significant difference in systolic areas, the diastolic area were lower in ITA than in AA, and lower in GEA than in AA and in ITA. These results clarified that arterial grafts which belong to the systolic-dominant systemic circulation have disadvantages over aorto-coronary bypass grafts, in terms of physiological suitabilities to the diastolic-dominant coronary circulation.