To investigate the superiority and key technical points of establishing a mouse cervical heterotopic heart transplantation model using the modified cuff technique.

The ascending aorta and pulmonary artery of the donor heart were anastomosed end-to-end to the recipient′s common carotid artery and external jugular vein, respectively, using a self-made tail-anchored cuff. Surgical success rate, operation time, and graft survival time were recorded. Pathological changes in the graft were assessed by HE staining. The experimental protocol included a pre-training phase and formal experimental phase, with mice in the formal phase divided into syngeneic control group and allogeneic transplant group. Survival curves were generated using the Kaplan-Meier method, and comparison was performed with the log-rank test. P<0.05 was considered statistically significant.

A total of 181 cases of mouse heterotopic heart transplantation were performed in the training phase, with a surgical success rate of 22.1% (40/181) and gradual reduction in operation time. Reasons for graft failure included failure of donor-recipient vascular connection, rupture during recipient vessel dissection, sleeve eversion technique failure, venous congestion at the anastomosis site, and postoperative chronic hemorrhage. The recipient preparation time, donor heart harvesting time, heart transplantation time, total operation time were (25.2±1.0) min, (14.7±0.5) min, (22.0±1.1) min and (60.0±1.2) min, respectively. One mouse died of venous congestion-induced cardiac arrest one day after the operation in both the syngeneic control group and allogeneic transplant group, and one mouse died of arterial anastomosis leakage in the allogeneic transplant group, yielding a success rate of 85.7% (18/21). The median graft survival time was 7.0 (5.0-7.0) d in the allogeneic transplant group and >100 d in the syngeneic control group (excepting 1 dead mouse). There was statistical significance for the cumulative survival rate of graft between the two groups (χ²=14.83, P<0.05). Histopathology revealed no myocyte necrosis or inflammatory infiltration in the syngeneic control group, whereas the allogeneic transplant group exhibited extensive lymphocytic and mononuclear cells infiltration, myocardial edema, hemorrhagic necrosis, and microvascular occlusion, consistent with acute rejection.

The application of cuff with tail-fixated shank prevents vascular slippage and significantly reduces operative difficulty, thereby establishing itself as the preferred methodology for developing heterotopic cervical heart transplantation models in mice.