星状神经节阻滞对兔心肌梗死后心功能的影响

Effect of stellate ganglion block on cardiac function after myocardial infarction in rabbits

目的探索左侧星状神经节阻滞(left stellate ganglion block,LSGB)、右侧星状神经节阻滞(right stellate ganglion block,RSGB)对兔心肌梗死后心功能的影响及其差异。方法以日本大耳白兔作为研究对象,开胸结扎冠状动脉左前降支建立心肌梗死动物模型,按简单随机法分为对照组、LSGB组以及RSGB组。对照组不做处理,后两组分别在左、右侧星状神经节处置管并每日给予0.25%罗哌卡因0.5 mL阻滞。检测并比较术前、术后1 d及术后2周血清肌酸激酶(creatine kinase,CK)、肌酸激酶同工酶(creatine kinase isoenzyme MB,CKMB)及心肌肌钙蛋白I(cardiac troponin I,cTnI)浓度。经胸超声心动图测量术前及术后2周左心室舒张末内径(left ventrieular end-diastolic intemal dimension,LVIDd)、左心室收缩末内径(left ventricular end-systolic internal dimension,LVIDs)、左心室射血分数(left ventricular ejection fraction,LVEF)和短轴缩短率(fractional shortening,FS)。结果兔心肌梗死动物模型建立效果确切,星状神经节阻滞后同侧霍纳综合征明显。术后1 d血清CK、CKMB及cTnI浓度较术前及术后2周明显升高,差异有统计学意义(P<0.05),但是3组间比较差异无统计学意义(P>0.05)。3组动物术后2周与术前相比,LVIDd、LVIDs明显增加、LVEF、FS明显下降,差异有统计学意义(P<0.05)。LSGB组和RSGB组术后2周LVEF、FS高于对照组,差异有统计学意义(P<0.05),而LSGB组和RSGB组术后2周LVEF、FS比较,差异无统计学意义(P>0.05)。结论 LSGB、RSGB对心肌梗死后心功能具有一定的改善作用,但两种处理方式的效果差异并不明显。

Objectives To study the effect of stellate ganglion block on cardiac function after myocardial infarction in rabbits and the difference between left and right stellate ganglion blocks （LSGB and RSGB）. Methods The Japanese white rabbit models of myocardial infarction were established through left anterior descending coronary artery ligation after thoracotomy. The rabbits were randomly divided into 3 groups： control group, LSGB group and RSGB group. No treatment was administrated in control group. In the other two groups, the left or right stellate ganglion was separated with a cervical medial incision and a tube was fixed beside the left or right stellate ganglion for nerve block with 0.5 mL of 0.25% ropivacaine each day. The serum concentrations of creatine kinase （CK）, creatine kinase isoenzyme MB （CKMB） and cardiac troponin I（cTnI） before, 1 day and 2 weeks after operation were tested. The left ventricular end- diastolic internal dimension （LVIDd）, left ventricular end-systolic internal dimension （LVIDs）, left ventricular ejection fraction （LVEF） and fractional shortening （FS） were measured with transthoracic echocardiography before and 2 weeks after operation. Results Electrocardiogram, observation of cardiac specimen and hematoxyliu-eosin staining in myocardium indicated that myocardial infarction models were successful. Ipsilateral Homer＇s syndrome was exactly observed after stellate ganglion block. Serum concentrations of CK, CKMB and cTnI 1 day after operation were higher than those before and 2 weeks after operation （P〈0.05）. However, no significant differences were found among the 3 groups （P〉0.05）. LVIDs and LVIDd increased, LVEF and FS decreased 2 weeks after operation comparing with those before operation in the 3 groups （P〈0.05）. LVEF and FS 2 weeks after operation were higher in LSGB and RSGB groups than in control group （P〈O.05）. However, there were no significant differences in LVEF and FS 2 weeks after operation between LSGB and RSGB groups （P〉0.05）. Conclusions Left or right stellate ganglion block can improve cardiac function after myocardial infarction with similar effects.