超声背向散射测定技术评价快速起搏兔右心房致心肌纤维化实验研究

Experimental study on ultrasonic backscatter in the evaluation of rapid atrial pacing induced myocardial fibrosis in abbits

目的建立快速心房起搏致兔心房颤动(房颤)模型,探讨超声背向散射测定技术评价心肌纤维化程度的价值。方法 16只新西兰大白兔随机分为假手术组和起搏组各8只。假手术组仅植入电极不行快速起搏,起搏组行短期快速起搏兔右心房12h致房颤模型。建立房颤兔模型后,2组行兔右心耳Masson染色和免疫组织化学法检测Ⅰ型和Ⅲ型胶原蛋白的表达情况;心脏超声检测2组房间隔和右心房后壁背向散射积分值和背向散射积分周期变化值。结果成功建立快速起搏右心房诱导房颤兔模型;Masson染色显示起搏组心肌纤维化明显增加;起搏组Ⅰ型及Ⅲ型胶原蛋白蛋白表达呈强阳性,假手术组呈弱阳性;起搏组房间隔和右心房后壁背向散射积分平均值((15.56±1.30)、(16.60±2.45)dB)较假手术组((8.24±0.85)、(7.58±0.56)dB)明显增高,背向散射积分周期变化值((1.08±0.13)、(1.56±0.15)dB)较假手术组((2.78±0.86)、(3.12±0.65)dB)明显降低(P<0.05)。结论超声背向散射测定技术评价快速起搏兔右心房致房性心律失常模型心肌纤维化程度有重要价值。

Objective To establish rapid atrial pacing induced atrial fibrillation（AF）rabbit models and explore the value of ultrasonic backscatter quantitative analysis to the evaluation of myocardial fibrosis.Methods Sixteen New Zealand white rabbits were randomly divided into sham operation group and pacing group,with 8rabbits in each group.Sham operation group was implanted electrodes,without rapid pacing.Pacing group was established AF models by short-term rapid pacing the right atrium for 12 hours.After the establishment of AF models,two groups were performed Masson staining,and the expressions of collagen Ⅰ and collagen Ⅲ proteins were detected by immunohistochemistry.The average image intensity（AII）and the cyclic variation of integrated backscatter（CVIB）were detected in atrial septum and posterior wall of the right atrium.Results The AF models were successfully established after inducing by rapid atrial pacing.Masson staining showed significantly aggravated myocardial fibrosis in pacing group.The expressions of collagenⅠandⅢ proteins were strong positive in pacing group,and were weakly positive in sham operation group.The AII values were（15.56±1.30）and（16.60±2.45）dB in pacing group,significantly higher than those in sham operation group（（8.24±0.85）and（7.58±0.56）dB）.CVIB values were significantly lower in pacing group（（1.08±0.13）,（1.56±0.15）dB）than those in sham operation group（（2.78±0.86）,（3.12±0.65）dB）（P〈0.05）.Conclusion Ultrasonic backscatter measurement technique has an important value to evaluating the degree of myocardial fibrosis induced by rapid atrial pacing in atrial arrhythmia rabbit models.