^(67)Ga心肌显像诊断心肌炎的实验研究

^(67)Ga myocardial imaging for the detection of myocarditis in experimental model

以柯萨奇 B_3病毒感染 BALB/c 小鼠,制备心肌炎模型,用^(67)Ga 心肌显像检测炎症心肌。结果显示,正常组20只小鼠心肌摄^(67)Ga 率很低,给药后24～72小时心肌显像均呈阴性。心肌炎组30只,给药后24、48及72小时炎症心肌的放射性浓聚均明显高于正常对照组,给药后48小时最高,且高出其他组织1.65～20.55倍,其放射性浓聚程度与心肌炎程度呈正相关;24小时心肌显像阴性,48小时及72小时心肌显像均呈阳性,3只心肌炎程度较重者96小时显像也呈阳性。故注射^(67)Ga 后48及72小时心肌显像能无创性地检测心肌炎症。

PURPOSE To assess the feasibility of ^(67)Ga myocardial imaging in detecting myocarditis.METHODS An exper- imental myocarditis model induced by Coxackic B3 virus in BALB/c mice was compared with normal controls in ^(67)Ga myocardial scintigraphy.RESULTS In normal mice group (n=20),tissue distribution studies documented low myocardial uptake of ^(67)Ga at 24～72 hours after administration.All had negative myocardial imagings.Contrarily,significant myocardial uptake of ^(67)Ga was found in the myocarditis mice group (n=30),in which the peak accumulation of ^(67)Ga in inflammatory myocardium was at 48 hours after injection,much higher than that of control group,and was 1.65～20.55 times higher than that of other tissues.The ^(67)Ga uptake was highly correlated with the extent of the myocardial lesions.Positive imagings were visualized at 48～72 hours af- ter ^(67)Ga administration,but myocardial imagings were negative at 24 and 96 hours,except 3 with severe pathologic lesions which bad positive imagings at 96 hour.CONCLUSIONS The study demonstrated that cardiac imaging with ^(67)Ga may be useful in the diagnosis of myocarditis in clinical.