Detection of viable myocardium in patients with myocardial infarction. comparison of nitrate 99mTc-MIBI with 201Tl reinjection tomography

Purpose: The accuracy of sublingual nitrate 99mTc-MIBI tomography (MB-N) in predicting out-come of percutaneous transluminal coronary angioplasty (PTCA) was investigated and compared with 201Tl reinjection imaging. Methods: 31 patients underwent 201Tl rest (Tl-R), reinjection imagings (Tl-RR), 99mTc-MIBI tomography on dipyridamole stress (MB-P) and at rest receiving sublingual nitrates (MB-N) within 2 weeks. The activity of segments (9 segments/patient) was quantified by circumferential profiles and was expressed as a percentage of peak activity in left ventricle. Results: Of 162 segments with reduction of MIBI uptake on stress imaging, 58% showed enhanced MIBI uptake on MB-N, which was similar to that on Tl-RR (61% vs 64%, P>0.05). The segmental activity was divided into 4 groups based on Tl-R and there was no difference between MB-N and Tl-RR in the segmental activity of each group. In 13 patients undergone PTCA, the percentages of positive and negative predicting of MB-N for the improvement of wall motion after PTCA were 82% and 88% and of Tl-RR were 78% and 90%, respectively. Conclusions: MB-N, a simple and practicable approach, can significantly improve the detection of viability in severe ischemia as well as 201Tl reinjection imaging