Williams S J, Dragotakos D L, Okada R D
E.I. du Pont de Nemours & Co. Inc., N. Billerica, MA 01862.
Eur J Nucl Med. 1989;15(6):287-91. doi: 10.1007/BF00435467.
Hexakis 99mTc-tertiary butyl isonitrile (99mTc-TBI) was studied as a cardiac perfusion imaging agent in nine dogs with partial occlusion of the LAD. Thirty min after applying the stenosis, 99mTc-TBI was injected into the right atrium (RA) in five dogs and left atrium (LA) in four dogs. Normal and ischemic zone regional myocardial 99mTc-TBI activities were monitored continuously for 4 h. Dogs with LA injections had minimal and equivalent 4 h fractional clearance from the normal and ischemic zones. Dogs with RA injections had minimal, but significantly lower 4 h fractional 99mTc clearances in the ischemic zone (0.08 +/- 0.08) compared to the normal zone (0.16 +/- 0.07, P less than 0.05). The delayed ischemic zone clearance is probably due to the high initial lung uptake observed after RA injection. Despite the differences in clearance, this minimal amount of redistribution could not be detected on gamma camera images. The minimal myocardial washout and redistribution, and the 140 keV gamma make 99mTc-TBI a promising cardiac perfusion imaging agent.
六甲基异腈锝-99m（99mTc-TBI）作为一种心脏灌注显像剂，在9只左前降支部分闭塞的犬身上进行了研究。施加狭窄30分钟后，5只犬经右心房（RA）注入99mTc-TBI，4只犬经左心房（LA）注入。连续4小时监测正常和缺血区局部心肌的99mTc-TBI活性。经左心房注射的犬，正常区和缺血区4小时的分数清除率最低且相当。经右心房注射的犬，缺血区4小时的99mTc分数清除率最低，但与正常区（0.16±0.07）相比显著降低（0.08±0.08，P<0.05）。缺血区清除延迟可能是由于经右心房注射后观察到的肺部高初始摄取。尽管清除率存在差异，但在γ相机图像上无法检测到这种最小量的再分布。最小的心肌洗脱和再分布，以及140keV的γ射线，使99mTc-TBI成为一种有前景的心脏灌注显像剂。
