坏死亲和性对比剂MRI显示梗死心肌及病理对照研究  

MRI with necrosis-avid contrast agent for the assessment of myocardial viability in a swine model

作　　者：靳激扬[1] 滕皋军[1] 冯毅[2] 吴燕平[2] 金琴娣[1] 王宇[2] 卢勤[1] 王臻[3] 章晓国[2] 汪盛齐[1] 陈峰[1] 倪以成[4] 

机构地区：[1]东南大学附属中大医院放射科,南京210009 [2]东南大学附属中大医院心内科,南京210009 [3]东南大学附属中大医院麻醉科,南京210009 [4]比利时鲁汶大学医学院医学影像部

出　　处：《中华放射学杂志》2007年第8期874-878,共5页Chinese Journal of Radiology

基　　金：东南大学科技基金(XJ 0590217)

摘　　要：目的通过冠状动脉注射坏死组织亲和性非卟啉类顺磁性对比剂(ECⅢ-60)后 MR 延时影像与病理对照的方法明确其强化区与梗死心肌的关系,并与静脉注射非特异性对比剂钆喷替酸葡甲胺(Gd-DTPA)比较,以期为 MRI 准确评价心肌活性提供可靠的病理依据。方法经导管采用闭胸法成功建立8只猪的急性心肌梗死再灌注模型。经静脉以0.2 mmol/kg 快速团注 Gd-DTPA 后行心电激发的心脏 MR 短轴面T_1WI,延时扫描至局部 Gd-DTPA 完全消失。然后再以0.0025 mmol/kg 经冠状动脉导管缓慢注入 ECⅢ-60后短轴面 T_1WI,延时成像至5 h。比较分析 ECⅢ-60增强 MRI 延时强化区和金标准病理所示梗死区的关系;并和 Gd-DTPA 增强 MRI 的对比增强效果(CR)与范围(RIS)进行比较。结果 ECⅢ-60增强 MRI 可见梗死区的信号较正常对照区明显升高(CR>3.0)并持续超过5 h,其强化区相对面积[占同层面左室面积的百分率为(11.84±3.63)%]与 TTC 染色心肌梗死面积[(11.78±3.64)%]一致(t=2.251,P>0.05),两者呈正相关,其决定系数为 r=0.999。Gd-DTPA 也能产生 CR>3.0的强化效果,但对梗死区的对比度在2 h 内逐步消失。结论坏死亲和性对比剂增强 MRI 能持续准确地反映心肌梗死,能成为冠状动脉介入术后心肌活力评估的有潜在价值的方法。Objective To determine the relationship between the delayed enhanced area on MRI revealed with necrosis-avid contrast agent （NACA） bis-Gd-DTPA-pamoic acid derivative （ EC Ⅲ-60） and the infarction area on pathologic examination, and compare it with an extracellular agent Gd-DTPA after intravenous injection. Methods The reperfused myocardial infarction model was created by minimally invasive close-chest method in eight pigs. After intravenous injection of Gd-DTPA （0. 2 mmol/kg）, all pigs were kept scanning with T1-weighted imaging until lesion enhancement vanished. Then they were intracoronarily infused with EC Ⅲ-60 （0.0025 mmol/kg） and imaged for 5 hrs. The extent of delayed enhanced area on EC Ⅲ-60 enhanced MRI was compared and correlated with TTC stained sections. Contrast ratio （CR） and relative infarct size （RIS） were quantified and compared with those of Gd-DTPA enhanced MRI. Results CR over 3.0 was obtained and it persisted over 5 hrs on EC Ⅲ-60 enhanced MRI. The spatial extent of delayed enhanced area （ 11.84 ± 3.63 ） % was consistent with the spatial extent of infarction area （ 11.78 ± 3.64 ） % （ t = 2. 251, P 〉 0. 05 ）. There was excellent correlation between the lesion size on EC Ⅲ-60 enhanced T1-weighted MR images and histomorphometry（ r =0. 999, P 〈0. 01 ）. CR over 3. 0 was also induced by Gd-DTPA, however, the enhancement vanished gradually in 2 hrs. Conclusions NACA can demarcate the myocardial infarction persistently and accurately. It is a potential method for postprocedural assessment of myocardial viability after coronary interventions.

关 键 词：动物实验 造影剂 磁共振成像 心肌梗死 

分 类 号：R445.2[医药卫生—影像医学与核医学] R542.22[医药卫生—诊断学]