Quantitative approach to radial artery patency

Abstract

Aim: Visual estimates of the severity of coronary stenosis are frequently very inaccurate. Angiography is inaccurate in assessing the functional significance of a coronary stenosis. Severity of stenosis in the native coronary artery is critical for both the short and long-term patency of the radial artery (RA), because of the potentially negative effects of competitive flow when the stenosis is below 70%. Material and Methods: A one hundred patients were selected. Radial artery is used for all patients during off-pump surgery. After all distal anastomoses are done and the systolic blood pressure reached over 100 mmHg, we have made arterial pressure measurement from the proximal side of radial artery graft. Both radial artery pressure and aortic pressure were recorded instantaneously. Systemic arterial pressure measurements are done from ascending aorta. Results: Serial postoperative coronary angiographies were performed at the first six postoperative months. We have detected ten radial artery graft occlusions and string sign. Five right coronary artery, four circumflex artery, and one diagonal artery radial artery grafts occluded. The percentage of systolic aortic and coronary pressure measurement (Ao/C-s%) on occluded graft patients was changed from 81 to 97. Percentage of diastolic aortic and coronary pressure measurement (Ao/C-d%) was changed from 83 to 90. Percentage of mean aortic and coronary pressure measurement (Ao/C-m%) was changed from 84 to 95. Conclusion: We concluded that; we can predict of radial artery prognosis based on the severity degree of coronary artery stenosis. We have found ten radial artery grafts occluded. However the patients are completely asymptomatic because of functionally insignificant lesions despite these lesions are considered visually significant on coronary angiogram. Unfortunately ten radial artery measurements are not enough for establishing a reliable cut-off value. We need more studies for creating a cut-off value determination.