Time course of technetium-99m sestamibi myocardial distribution in dogs with a permanent or transient coronary occlusion

• Published in: European Journal of Nuclear Medicine 1994-06, Vol.21 (6), p.481-487
• Main Authors: YAHYE MERHI, ARSENAULT, A, LATOUR, J.-G
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Cardiovascular system; Collateral Circulation - physiology; Constriction; Coronary Circulation - physiology; Coronary Disease - diagnostic imaging; Dogs; Female; Heart - diagnostic imaging; Investigative techniques, diagnostic techniques (general aspects); Male; Medical sciences; Microspheres; Myocardial Infarction - diagnostic imaging; Myocardial Reperfusion; Radionuclide Imaging; Radionuclide investigations; Technetium Tc 99m Sestamibi; Time Factors
• ISSN: 0340-6997; 1619-7089
• DOI: 10.1007/BF00173032

The influence of duration of coronary occlusion and reperfusion on technetium-99m hexakis-2-methoxyisobutylisonitrile (99mTc-sestamibi) myocardial redistribution between necrotic, salvaged and non-ischaemic myocardium was investigated in dogs submitted either to a 90-min or a 24-h permanent left descending coronary artery occlusion (groups 1 and 2) or to a 90-min occlusion followed by 30 min, 6 h or 22.5 h of reperfusion (groups 3, 4 and 5). In all groups, 99mTc-sestamibi and radiolabelled microspheres were injected at 45 min of occlusion. After delimiting the area at risk and the infarct by Evans blue perfusion and triphenyltetrazolium chloride staining, radioactivity of heart slices from normal, viable-ischaemic and necrotic myocardium was measured in a gamma counter. A significant (P < 0.001) linear relationship between 99mTc-sestamibi distribution and myocardial blood flow was observed in the area at risk of groups 1 (r = 0.92), 2 (r = 0.84), 3 (r = 0.90), 4 (r = 0.93) and 5 (r = 0.58). In all groups, the mean percentage of 99mTc-sestamibi uptake in the ischaemic over normal zone overestimated significantly (P < 0.05) the mean percentage of the ratio in myocardial blood flow measured with microspheres (group 1: 13.3 +/- 1.4 vs. 7.7 +/- 1.2; group 2: 15.9 +/- 2.0 vs 5.6 +/- 1.2; group 3: 14.9 +/- 1.6 vs 6.2 +/- 1.0; group 4: 20.9 +/- 1.7 vs 10.9 +/- 1.8; group 5: 51.0 +/- 2.7 vs 14.0 +/- 2.0).