Evaluation of Result of Coronary Artery Bypass Graft Surgery by Using Pre and Postoperative Myocardial SPECT

Lee, Jang Hoon; Han, Sung Sae; Lee, Jung Cheul; Lee, Dong Hyup; Jung, Tae Eun

Abstract

This study was purposed to assess the result of coronary artery bypass graft surgery by analyzing and comparing the pre and postoperative myocardial perfusion state quantitatively by using myocardial SPECT. Twenty patients who received coronary artery bypass graft surgery since 1993 underwent both preoperative and postoperative myocardial SPECT and the result were analyzed. The mean age was 56.4+/-9.0 years, and the patients were composed of thirteen males and seven females. For quantitative analysis, we used polar maps of SPECT generated by Cedars-Sinai Medical Center program and we calculated perfusion scores, ischemic myocardial area ratios and reperfusion scores from polar maps. Preoperative mean stress/rest perfusion score was 7.3+/-1.1/7.7+/-1.0 and postoperative score was 8.1+/-1.1/8.3+/-1.1. Preoperative mean stress ischemic myocardial area ratio was 0.32+/-0.2 and postoperative ratio was 0.15+/-0.1. Postoperative mean perfusion score was significantly increased but, on the other hand, mean ischemic myocardial area ratio was significantly decreased as compared with preoperative values(p<0.01). Preoperative mean perfusion score of patients with postoperative reperfusion score more than 1.5 was significantly higher(p<0.01) than that of patients with postoperative reperfusion score less than 1.5. Preoperative perfusion scores of coronary artery territories that had fixed perfusion defect at myocardial SPECT were significantly low(4.3+/-0.5/4.6+/-0.6, stress/rest), nevertheless it proved quantitatively that there was improvement in myocardial perfusion after surgery by showing improved perfusion scores postoperatively. In conclusion, myocardial SPECT is useful method for quantitative analysis of the myocardial perfusion state after coronary artery bypass grafting surgery.