Scintigraphic demonstration of myocardial perfusion and ischaemia associated with coronary artery bypass grafting

Abstract

Objectives. To assess if myocardial perfusion scintigraphy (MPS) at rest can be of value in elucidating myocardial perfusion, ischaemia and perioperative myocardial infarction (PMI) associated with coronary artery bypass graft (CABG) surgery. Design. This was a prospective randomized study of patients undergoing elective CABG. Forty-eight patients in the control group underwent serial ECG recordings and measurements of CK-MB and cTnT. Fifty-four patients in the study group were additionally examined with MPS preoperatively and 2-4 days and 6 weeks postoperatively. Results. The study showed a highly significant (p<0.001) improvement in myocardial radionuclide uptake from preoperatively to 2-4 days postoperatively. Judged from ECG and enzymatic changes, two control patients and one study patient only had PMI and no additional cases of PMI were demonstrated by MPS. Conclusion. MPS at rest showed that CABG significantly improved myocardial perfusion, by demonstrating an increase in radionuclide uptake. In diagnosing PMI, we found that MPS provided no additional information beyond cardiac biochemical markers and ECG changes.