Intraoperative detection of unsuspected distal coronary obstruction by thermal coronary angiography.

Intraoperative assessment of graft patency and completeness of revascularization can increase the success of coronary artery bypass grafting. A 56-year-old man underwent a quadruple bypass operation. Flow in the graft to the anterior descending artery was verified after completion of the distal anastomosis using a Doppler flow detector. Visualization of the native artery by thermal coronary angiography demonstrated that the flow passed into the second diagonal branch and not into the distal anterior descending artery, which had an unsuspected obstruction just distal to the anastomosis. The obstruction was dilated. Patency was verified with cold solution, and flow of warm blood to the entire artery was accomplished. This case demonstrates how the early (intraoperative) recognition of an unsuspected coronary obstruction using an infrared imaging system can improve the results of myocardial revascularization and avoid potential postoperative complications.