From March 1988 to March 1992, 69 patients with coronary artery disease (CAD) and left ventricular dysfunction (LVD) were referred to our Institute for surgical decision making. Sixty-nine (8.2%) had LVD. In 39/69 patients we performed the identification of viable myocardium with the use of [18F] FDG/PET in fasting conditions. We divided patients with LVD into 3 groups: Group A (30 patients) operated on without preoperative [18F] FDG/PET, Group B (32 patients) with FDG uptake in akinetic segments, and Group C (7 patients) with no FDG uptake; there was no significant difference among the 3 groups in age, sex, CAD, risk factors and ejection fraction EF (Group A: 29.1 +/- 6.6%, range 16-40; Group B: 32.9 +/- 6.5%, range 20-40; Group C: 26.5 +/- 6.8%, range 18-37). All patients underwent [99mTc] MIBI/SPET to assess perfusion at rest and [99mTc] MIBI first pass radionuclide angiography to assess the EF. The study of perfusion and EF was repeated 6 months postoperatively in Group A and B. Myocardial protection was achieved according to the Buckberg protocol. Operative results in Group A and B were respectively: in-hospital deaths 2 (6.6%) versus 0 (NS), perioperative myocardial infarction 1 (3.3%) versus 1 (3.1%) (NS), IABP 10 (33.3%) versus 4 (12.5%) (p = 0.048). Postoperative EF improved both in Group A (35.1 +/- 7.1%, range 20-50; p = 0.01) and in Group B (44.2 +/- 7.7%, range 26-62; p < 0.001). In Group C 6/7 patients were scheduled for heart transplantation according to standard criteria.(ABSTRACT TRUNCATED AT 250 WORDS)