THERMAL CORONARY ANGIOGRAPHY - A METHOD FOR ASSESSING GRAFT PATENCY AND CORONARY ANATOMY IN CORONARY-BYPASS SURGERY - UPDATE

Thermal coronary angiography was evaluated in 50 patients undergoing 1 37 saphenous vein and 48 internal mammary artery bypass grafts. A tota l of 177 thermal coronary angiograms were performed after completion o f the distal anastomoses by injection of cold cardioplegia into the ve in or by reperfusion with warmer blood in the internal mammary artery grafts. These angiograms provided details of graft and anastomosis pat ency, flow directions, and presence of native coronary stenoses. Tempe rature differences between the injectant and the epimyocardium of grea ter than 4 degrees C resulted in high-contrast images. Thermal coronar y angiograms were obtained in 173 of the 177 studied bypass grafts; 17 2 grafts were patent, and 1 internal mammary artery graft was occluded . Unsuspected stenoses were detected at the site of four distal anasto moses. Subsequently, two anastomoses were successfully revised and thr ee additional grafts performed. Ninety-six native coronary stenoses we re located in the recipient coronary arteries. In ten instances, the t hermal coronary angiograms were obscured by excess fat or myocardium, thereby impeding correct image analysis. We conclude that thermal coro nary angiography can be clinically relevant and helps improve decision making during coronary artery bypass operations.