Maes A F, Borgers M, Flameng W, Nuyts J L, van de Werf F, Ausma J J, Sergeant P, Mortelmans L A
Department of Nuclear Medicine, K. U. Leuven, Belgium.
J Am Coll Cardiol. 1997 Jan;29(1):62-8. doi: 10.1016/s0735-1097(96)00442-1.
The value of 99mTc-sestamibi (2-methoxy-isobutyl isonitrile [MIBI]) as a viability tracer was investigated in patients undergoing coronary artery bypass graft surgery.
Initial studies claim that rest MIBI single-photon emission computed tomographic (SPECT) studies can be used to assess myocardial viability.
Thirty patients with a severely stenosed left anterior descending coronary artery and wall motion abnormalities were prospectively included. The patients underwent a MIBI rest study, a positron emission tomographic (PET) flow (13NH3) and metabolism (18F-deoxyglucose) study and nuclear angiography before undergoing bypass surgery. A preoperative transmural biopsy specimen was taken from the left ventricular anterior wall. Morphometry was performed to assess percent fibrosis. After 3 months, radionuclide angiography was repeated.
Statistically significant higher MIBI values were found in the group with myocardial viability as assessed by PET than in the group with PET-assessed nonviability (p < 0.01). Significantly higher MIBI values were found in the group with enhanced contractility at 3 months (76 +/- 13% vs. 53 +/- 22%, p < 0.01). A linear relation was found between MIBI uptake and percent fibrosis in the biopsy specimen (r = 0.78, p < 0.00001). When maximizing the threshold for assessment of viability with MIBI by using functional improvement as the reference standard, a cutoff value of 50% was found, with positive and negative predictive values of 82% and 78%, respectively.
99mTc MIBI uptake was significantly higher in PET-assessed viable areas and in regions with enhanced contractility at 3 months. A linear relation was found between percent fibrosis and MIBI uptake. An optimal threshold of 50% was found for prediction of functional recovery.
在接受冠状动脉搭桥手术的患者中研究99m锝-甲氧基异丁基异腈（MIBI）作为存活示踪剂的价值。
初步研究称静息MIBI单光子发射计算机断层扫描（SPECT）研究可用于评估心肌存活情况。
前瞻性纳入30例左前降支冠状动脉严重狭窄且有室壁运动异常的患者。这些患者在接受搭桥手术前进行了MIBI静息研究、正电子发射断层扫描（PET）血流（13NH3）和代谢（18F-脱氧葡萄糖）研究以及核血管造影。术前从左心室前壁获取透壁活检标本。进行形态测量以评估纤维化百分比。3个月后，重复放射性核素血管造影。
通过PET评估有心肌存活的组中，MIBI值在统计学上显著高于PET评估为无存活的组（p < 0.01）。在3个月时收缩功能增强的组中发现MIBI值显著更高（76±13%对53±22%，p < 0.01）。在活检标本中发现MIBI摄取与纤维化百分比之间存在线性关系（r = 0.78，p < 0.00001）。以功能改善作为参考标准，当最大化用MIBI评估存活的阈值时，发现截断值为50%，阳性和阴性预测值分别为82%和78%。
在PET评估的存活区域以及3个月时收缩功能增强的区域，99mTc MIBI摄取显著更高。发现纤维化百分比与MIBI摄取之间存在线性关系。发现预测功能恢复的最佳阈值为50%。
