[Visualization of aorto-coronary bypass grafts with the aid of non-dynamic computer tomography].

To evaluate computer tomography (CT) for assessment of aorto-coronary bypass graft patency, 45 patients with 85 grafts were studied by non-dynamic CT before and after intravenous bolus injection of 50 ml contrast material. 28 patients had undergone postoperative coronary angiography (37 grafts patent, 11 occluded), while 17 (37 grafts) were studied in the early postoperative period without angiographic confirmation. 60 of 74 grafts (81.1%) which were angiographically patent or not checked by postoperative angiography could be visualized by CT. In patients in whom graft patency was documented by angiography, 32 of 37 grafts (86.5%) were identified correctly, including all 18 grafts (100%) to the left anterior descending branch (LAD). With the exception of one LAD graft which was judged differently by the two evaluators, none of the 11 definitely occluded grafts could be visualized by CT. The results suggest that non-dynamic CT allows correct identification of patent aorto-coronary bypass grafts in a high percentage of cases. So far, however, the method does not allow any deduction as to the functional status of the grafts.