Beneficial effect of coronary artery bypass grafting as assessed by quantitative gated single-photon emission computed tomography

The development of quantitative gated single-photon emission computed tomography (SPECT) has enabled the assessment of left ventricular perfusion, function and wall thickness in a single examination. Accordingly, the present study used gated SPECT to assess the benefit of coronary artery bypass grafting (CABG) in. patients with coronary artery disease; 47 of those patients were evaluated before and 5 months after CABG. As a result of coronary revascularization, a significant improvement was observed in global ejection fraction (50 +/- 12 --> 53 +/- 11%; p < 0.05). In 107 revascularized territories, the average regional reversible defect score (0.8 +/- 0.5 --> 0.2 +/- 0.3; p < 0.0001), average regional perfusion score at rest (0.6 +/- 0.6 --> 0.3 +/- 0.4; p < 0.0001), average regional wall motion score (0.9 +/- 0.7 --> 0.7 +/- 0.5; p < 0.05), and end-diastolic wall thickness (8.1 +/- 1.3 --> 8.6 +/- 1.5 mm; p < 0.0005) all improved significantly. Even in 34 non-revascularized territories, the average regional reversible defect score (0.5 +/- 0.7 --> 0.2 +/- 0.5; p < 0.03), average regional wall motion score (0.8 +/- 1.1 --> 0.5 +/- 1.0; p < 0.03) and end-diastolic wall thickness (8.0 +/- 1.4 --> 9.1 +/- 2.0 mm; p < 0.03) all improved significantly. These results indicate that improvement in myocardial ischemia, hibernation and left ventricular function with CABG can be assessed in detail with gated SPECT.