大鼠室壁瘤左心室重建模型的建立

目的探讨建立大鼠室壁瘤左心室重建(LVR)动物模型的可行性。方法对35只成年雄性Sprague-Dawley(SD)大鼠实施左冠状动脉前降支结扎以制作心肌梗死后室壁瘤(LVA)模型,4周后,对符合入选标准的16只LVA模型实施LVR手术,作为实验组;另10只模型行开胸手术作为对照组,在术后3 d、2周、4周分别以超声心动图评价两组大鼠心功能情况,以直视摄片、Masson’s Trichrome染色评价室壁瘤切除的彻底程度。结果 LVA模型及LVR模型的死亡率分别为11.4%(4/35)及18.8%(3/16),建模成功率分别为74.3%(26/35)和81.3%(13/16)。直视摄片及Masson’s Trichrome染色提示补片完全替代心肌梗死瘢痕。超声心动图提示:行LVR手术的实验组动物的左心室收缩期末内径(LVESD)及左心室短轴缩短率(FS)在术后3 d即较对照组有所改善术后3 d:LVESD(5.00±0.87)mm vs.(5.90±0.92)mm,P<0.05;FS(34.20%±6.80%)vs.(26.60%±6.12%),P<0.01],随着时间的推移,施行LVR手术的实验组大鼠比对照组更好地维持了左心形态及收缩功能术后2周:左心室舒张期末内径(LVEDD)(7.60±0.56)mm vs.(8.50±1.08)mm,P<0.01;LVESD(5.10±0.65)mm vs.(6.69±0.89)mm,P<0.001;FS(31.90%±6.90%)vs.(21.10%±6.17%),P<0.001;术后4周:LVEDD(7.70±0.50)mm vs(.9.10±0.89)mm,P<0.001;LVESD(5.20±0.39)mm vs.(7.20±0.95)mm,P<0.001;FS(31.80%±2.40%)vs.(20.20%±4.17%),P<0.001]。结论大鼠LVR模型可作为组织工程心肌补片(EHT)研究中一种稳定、可靠、经济的初选模型。

Left Ventricular Reconstruction in a Rat Model with Post-infarction Ventricular Aneurysm

Objective To investigate the experience of left ventricular reconstruction(LVR)in a rat model with post-infarction ventricular aneurysm.Methods A total of 35 male Sprague-Dawley(SD) rats underwent left anterior descending artery(LAD) ligation to create a left ventricular aneurysm(LVA) model following myocardial infarction.Four weeks later,16 rats with LVA that met the inclusion criteria underwent LVR as the experiment group(LVR group).Another 10 rats with LVA underwent thoracotomy as the control group.Three days,2 weeks,and 4 weeks after the second operation,all the rats were examined by echocardiography to evaluate the cardiac function.At the end of the study,photography and Masson’s Trichrome staining were used to evaluate the completeness of LVA resection.Results The surgical mortality of LVA and LVR generation was 11.4%(4/35)and 18.8%(3/16) respectively,with the success rate 74.3%(26/35)for LVA model and 81.3%(13/16)for LVR model.Photography and Masson’s Trichrome staining identified complete replacement of ventricular scar by patch.Three days after the second operation,echocardiography illustrated that the left ventricular end-systolic diameter(LVESD)and fractional shortening(FS) of the LVR group were significantly improved compared with the control group(LVESD 5.00±0.87 mm versus 5.90±0.92 mm,P<0.05,FS 34.20%± 6.80% versus 26.60%±6.12%,P<0.01).The cardiac structure and function of LVR group were also significantly improved 2 weeks and 4 weeks after the second operation compared with the control group(2 weeks:left ventricular end-diastolic diameter(LVEDD)7.60±0.56 mm versus 8.50±1.08 mm,P<0.01;LVESD 5.10±0.65 mm versus 6.69±0.89 mm,P<0.001;FS 31.90%±6.90% versus 21.10%±6.17%,P<0.001;4 weeks:LVEDD7.70±0.50 mm versus 9.10±0.89 mm,P<0.001;LVESD5.20±0.39 mm versus 7.20±0.95 mm,P<0.001;FS 31.80%±2.40% versus 20.20%±4.17%,P<0.001).Conclusions LVR rat can be used as a stable,reliable and economic screening model in engineered heart tissue(EHT) research.