Wikström M, Martinussen H J, Ericsson A, Wikström G, Waldenström A, Hemmingsson A
Department of Diagnostic Radiology, Akademiska Sjukhuset, University of Uppsala, Sweden.
Acta Radiol. 1993 Jan;34(1):64-71.
Myocardial infarction was induced by ligating a diagonal branch of the left anterior descending artery in 18 pigs. All pigs were sacrificed 6 h after the occlusion. Dysprosium diethylenetriamine-pentaacetic acid bismethylamide (Dy-DTPA-BMA, 1.0 mmol/kg) was administered i.v. to 6 pigs, starting 3 min before sacrifice (injection time approximately 1 min). In a second group of 6 pigs, a double-contrast technique was used, consisting of an i.v. injection of gadolinium-DTPA-BMA (0.4 mmol/kg) 2 h before sacrifice, followed by an i.v. injection of Dy-DTPA-BMA (1.0 mmol/kg) 3 min before sacrifice. Six additional pigs, subjected to 6 h of coronary artery occlusion without administration of contrast medium, served as controls. The hearts were excised and imaged with MR. In the control animals, the infarctions demonstrated an increased signal intensity in the proton density- and T2-weighted images. Administration of Dy-DTPA-BMA primarily improved infarct visualization in the proton density- and T2-weighted images, due to reduction of signal intensity in nonischemic myocardium. The double-contrast technique further improved infarct visualization in all sequences.
通过结扎18头猪的左前降支对角支诱导心肌梗死。所有猪在闭塞后6小时处死。给6头猪静脉注射二乙三胺五乙酸镝双甲酰胺（Dy-DTPA-BMA，1.0 mmol/kg），在处死前3分钟开始注射（注射时间约1分钟）。在另一组6头猪中，采用双对比技术，即在处死前2小时静脉注射钆-DTPA-BMA（0.4 mmol/kg），然后在处死前3分钟静脉注射Dy-DTPA-BMA（1.0 mmol/kg）。另外6头猪在冠状动脉闭塞6小时且未注射造影剂的情况下作为对照。取出心脏并用磁共振成像。在对照动物中，梗死灶在质子密度加权像和T2加权像上显示信号强度增加。注射Dy-DTPA-BMA主要改善了质子密度加权像和T2加权像上梗死灶的显影，这是由于非缺血心肌信号强度降低所致。双对比技术在所有序列中进一步改善了梗死灶的显影。
