Thermal coronary angiography: A method for assessing graft patency and coronary anatomy in coronary bypass surgery (original) (raw)

Thermal coronary angiography was evaluated in 50 patients undergoing 137 saphenous vein and 48 internal mammary artery bypass grafts. A total of 177 thermal coronary angiograms were performed after completion of the distal anastomoses by injection of cold cardioplegia into the vein or by reperfusion with warmer blood in the internal mammary artery grafts. These angiograms provided details of graft and anastomosis patency, flow directions, and presence of native coronary stenoses. Temperature differences between the injectant and the epimyocardium of greater than 4°C resulted in highcontrast images. Thermal coronary angiograms were obtained in 173 of the 177 studied bypass grafts; 172 grafts hermography is a technique for recording, in color-T coded images, small temperature differences between adjacent structures. Modern infrared imaging systems consist of a scanning thermal camera, a video monitor, and a videotape recorder. Infrared radiation is detected and quantitated by special heat detectors in the scanner; it is then transformed to an electrical signal and displayed as a thermal image on a monitor. Recent technical advances in thermographic imaging have led to the development of systems that are more accurate, can be linked to digital image processors, and therefore are suitable for operating room use.