Myocardial blood perfusion （MBP） ECT and quantitative analysis were performed in 10 canines with experimental acute myocardial infarct（AMI）. The accuracy of main myocardial quantitative index

including defect volume（DV） and defect fraction（DF）

was estimated and correlated with histchemical staining （HS） of infarcted area. Other 21/AMI canines were divided into Nd:YAG laser tyansmyocardial revascularization treated group LTMR and control group. All canines were performed MBP ECT after experimental AMI. Results found that the infarcted volume （IV） measured by HS has well correlated （r=0.88） with DV estimated by myocardial quantitative analysis. But the DF values calculated by both methods was not significantly different （t= 1.28 P

>

0.05）. In LTMR group 27.5% ± 3.9%

the DF is smaller than control group 32.1% ± 4.6% （t = 2.49 P

<

0.05）. Results indicate that

99m

Tc-MIBI myocardial perfusion SPECT and quantitative study can accurately predict the myocardial blood flow and magnitude of injured myocardium. Nd:YAG LTMR could improve myocardial blood perfusion of ischemic myocardium and decrease effectively the infarct areas.