Identification of viable myocardium by nitroglycerin 99mTc-MIBI myocardial tomography in patients with acute myocardial infarction and comparison with echocardiography during infusion of dobutamine

PURPOSE: To evaluate the concordance between nitroglycerin (NTG) 99mTc-MIBI myocardial tomography and dobutamine echocardiography (DSE) in detecting viable myocardium of the patients with acute myocardial infarction (AMI). METHODS: 36 patients with AMI were studied using NTG 99mTc-MIBI SPECT and echocardiography during infusion of dobutamine in order to identity myocardial viability. All subjects underwent NTG 99mTc-MIBI SPECT and DSE within 3 weeks after infarction. RESULTS: Out of 109 segments with non-perfusion in rest SPECT, 43 segments (39%) had improvement of perfusion in NTG 99mTc-MIBI SPECT, 94 segments with non-kinesic at baseline, after dobutamine infusion by 10 μg·kg-1·min-1, 35 segments (37%) became normo-kinetic or hypo-kinetic. There was no significant difference between NTG 99mTc-MIBI SPECT and DSE (x2 = 0.105, P>0.05). In 92 segments detected by both techniques: 29 segments were viable and 49 segments were nonviable. There was a good concordance between the two techniques [84.8%(78/92), K = 0.68]. CONCLUSION: NTG 99mTc-MIBI myocardial tomography and echocardiography during infusion of low dose dobutamine is a safe and reliable method for identifying myocardial viability after AMI. A good concordance between two techniques was observed