小型猪慢性心肌缺血心衰模型的建立与评价

Establishment and evaluation of congestive heart failure models induced by chronic myocardial ischemia in minipigs

目的:建立慢性心肌缺血致心力衰竭的动物模型。方法:小型猪18只,随机分为假手术组(n=4)和模型组(n=14),模型组开胸于前降支近端放置ameroid缩窄环,假手术组分离前降支不套环。术后4周,行单光子发射计算机断层成像(SPECT)观察心脏灌注情况。应用无创超声心动图、有创血流动力学检查并评价心脏的舒缩功能。应用放射免疫测定法检测血清脑钠尿肽(BNP)、心肌肌钙蛋白T(cTnT)、肌酸激酶同工酶(CK-MB)、肿瘤坏死因子α(TNF-α)、白介素6(IL-6)、内皮素1(ET-1)和血管紧张素Ⅱ(AngⅡ)等浓度的变化。结果:模型组死亡2只,其余16只动物手术顺利完成。SPECT显示,模型组前降支供血区域心肌存在严重灌注障碍;假手术组无明显灌注缺损。超声心动图和血流动力学检查提示,模型组心脏的收缩和舒张功能严重受损,并发生心腔扩张,同时血清BNP的水平增高,心肌损伤标记物、炎性因子和神经体液因子的浓度也明显增高;假手术组上述参数均无显著改变。结论:在猪的前降支近端放置ameroid缩窄环是制作慢性心肌缺血心力衰竭动物模型的有效方法。

AIM： To establish an animal model of congestive heart failure （CHF） induced by chronic myocardial ischemia. METHODS： Eighteen minipigs were randomized to sham group （n =4） and model group （n = 14）. Thoracotomies were performed in both groups and the left anterior descending branches （LADs） were constricted by ameroid constrictors only in model group. Four weeks after surgery., single photon emission computed tomography （SPECT）, echocardiography and hemodynamie measurements were performed, and serum concentrations of brain natriuretic peptide （BNP）, cardiac troponin T （cTnT）, MB isoenzyme of creatine kinase （CK-MB）, tumor necrosis factor c~ （TNF-α）, interleukin-6 （IL-6）, endothelin-1 （ET-1） amt angiotensin II （Aug Ⅱ） were determined by radioimmunoassay. RESULTS： Sixteen animals survived the surgery and two animals in the model group died. SPECT showed severe perfusion defects in the LAD-dependent area in model group, whereas no obvious defects were observed in sham group. Echocardiographic and hemodynamic parameters showed severe systolic and diastolic dysfunction of the hearts in model group in which the c, oncentrations of BNP, markers of myocardial injury, inflammatory factors and neurohormonal factors increased. CONCLUSION： Implan- tation of ameroid constrictor in the initial segment of the LAD is an effective way to establish the model of CHF induced by chronic myocardial isehemia in minipigs.