A previous decision analysis examined a patient with severe CAD, diminished ventricular function, and an abdominal aortic aneurysm and also concluded that CABG followed by aneurysm repair was optimal. This patient, who had well-preserved cardiac function but severely compromised pulmonary status, stood to gain less from CABG than would a patient with more severe coronary disease, thus accounting for the "close-call" between the CABG-AAA and AAA only strategies. Nevertheless, the analysis did emphasize the benefit of aneurysm repair, whether done alone or after CABG. The analysis also highlighted the significant risk of aneurysm rupture the patient is exposed to while recovering from CABG surgery. The operative mortality risks of the two procedures are similar; thus, the patient's total operative risk is approximately doubled if he undergoes both procedures rather than aneurysm repair alone. The key question raised by the analysis is whether this double jeopardy is more than compensated by the degree to which prior CABG reduces both short-term cardiac risk at subsequent aneurysm repair and long-term cardiac mortality. For this patient, who had good cardiac function, the gains appeared sufficient to offset the interval risk of aneurysm rupture and the additional risk associated with a surgical procedures. THE REAL WORLD The patient indeed underwent and tolerated CABG, although he had a stormy prolonged postoperative course due to pulmonary failure. After discharge from the hospital, he declined readmission for repair of the aneurysm. We did not model that possibility, clearly an inadequacy in our tree. Some six months later, the patient was still alive and was, reluctantly, readmitted for aneurysmorrhaphy. At that time, however, his pulmonary function had deteriorated and both the anesthesiologist and the pulmonary consultant stated unequivocally that further surgery was now impossible. In retrospect, the expected utility of CABG without aneurysm repair (thus providing only a decrease in the long-term mortality risk from his CAD) would have been 1.95 (DEALE) or 2.06 (Markov) years. Sensitivity analysis revealed that, even if long-term cardiac risk were completely eliminated by CABG, immediate aneurysm repair would have been a better approach had the patient's physicians known he would be likely to refuse or not be a candidate for the second operation. In summary, although the patient's comorbidities did indeed place him at significant operative risk for either aneurysmorrhaphy alone or two sequential procedures, the benefits to be gained were shown to far outweigh the risks when compared with expectant observation.(ABSTRACT TRUNCATED AT 400 WORDS)