The internal thoracic artery (ITA) is considered to be the conduit of choice for coronary bypass (CABG), but there has been some reluctance to utilize the ITA for revascularization in emergency situations. In a 9-year retrospective analysis from 1986 through 1993, 484 patients had emergency CABG, 237 were not associated with failed PTCA (noninstrumented) and 247 were within 24 hours of PTCA (instrumented). About 62% of noninstrumented and 49.3% of instrumented patients received one or more ITA grafts, the others receiving only saphenous vein grafts (SVGs). Those who received an ITA graft tended toward male sex, better ejection fraction, and a generally lower clinical risk score. Instrumented patients tended toward a lower incidence of diabetes and left main coronary disease, higher ejection fraction, and lower clinical risk score than noninstrumented patients. The postoperative results were not significantly different between ITA and SVG groups with respect to new Q waves, need for reexploration, sternal wound infection, respiratory complications, or stroke. However, ITA patients more often had an event-free postoperative course, received fewer blood transfusions, and experienced fewer cardiac deaths (2.7% vs 9.4%, p < 0.01). There were few obvious differences in postoperative results between instrumented and noninstrumented patients. These results indicate that the ITA can be used for emergency CABG in selected patients with good results.