二维斑点追踪成像联合ICAM-1靶向超声造影检测心脏移植早期急性排异反应的研究

Detection of acute cellular rejection in heart transplantation at the early stage using two-dimensional speckletracking imaging and ICAM-l-targeted myocardial contrast echocardiography

目的应用二维斑点追踪成像（2D-STI）联合内皮细胞表面黏附因子（ICAM-1）靶向心肌声学造影早期判定心脏移植急性排异反应的发生。方法建立48只大鼠腹部异位心脏移植模型，其中同种异体移植（ALLO）24只，同系移植（ISO）24只，分别分成3组，于移植术后第1、3、5d进行超声心动图、2I）nSTI检查及ICAM-1靶向超声造影检查。成像后取材病理学检测心肌排异反应及ICAM-1表达。结果术后第5d，ALLO组大鼠超声心动图参数与ISO组相比，差异均具有统计学意义（均P〈0．05）。术后第3d，ALLO组左室收缩期峰值整体圆周应变及应变率（GCS、GCSr）、心内膜下心肌圆周应变（CS）开始出现降低，与Is0组相比，差异均有统计学意义（均P〈O．05）。术后第5d的各项应变值参数差异均有统计学意义（均P〈0．05）。ICAM-1靶向心肌超声造影显示：移植后第3d及第5d，ALLO组的心肌声学强度高于ISO组，差异均有统计学意义（均P〈0．05）。结论2D-STI联合ICAM-1靶向超声造影能够检测心脏移植的早期急性排异反应。

Objective To investigate whether two-dimension speckle tracking imaging（2I）-STI） and ICAM-l-targeted myocardial contrast echocardiography could detect the acute cellular rejection of heart transplantation at the early stage. Methods The abdominal heterotopic heart transplantation model was successfully established using Wistar and SD rats. Forty-eight rats were divided into allografts （ALLO） group （ n = 24） and isografts（ISO） group （ n = 24）. Echocardiography, 2D-STI and ICAM-1 targeted myocardial contrast echocardiography were performed at 1,3,5 day after transplantation respectively. After ultrasound imaging, transplanted hearts were harvested for Hematoxylin-eosin staining and immunofluorescence histochemistry to evaluate acute cellular rejection and ICAM-I expression. Results There were obvious difference between ALLO group and ISO group in echocardiographic parameters at 5 days after transplantation surgery （all P 〈0. 05）. Compared with those in ISO group, global circumferential strain and strain rate （GCS, GCSr）, and circumferential strain of endo myocardium（CSendo） decreased in ALLO group at day 3 post-transplantation （all P 〈0.05）. Compared with those in ISO group, all strain parameters in ALLO decreased significantly at postoperative day 5 （all P 〈 0.05）. Myocardial contrast echocardiography using ICAM I targeted microbubbles showed that the video intensity in ALLO group was significant higher than that in ISO group at postoperative day 3 and day 5 （all P 〈0.05）. Conclusions 2D STI and myocardial contrast echocardiography using ICAM-1 targeted microbubbles are sensitive and useful for detecting heart transplant acute rejection at the early stage.