A New Modified Technique for Heterotopic Femoral Heart Transplantation in Rats

Abbott developed the first experimental accessory heart transplant rat model in 1964. This intra-abdominal model required a labor-intensive aortic anastomosis. In 1971, Heron modified the operation by using sutureless cervical vessel anastomoses. Rao and Lisitza developed a femoral heart accessory transplant model in 1985. Our goal was to improve this femoral model for the study of cardiac transplantation between both syngeneic and allogeneic rats.ACI and Lewis rats weighing 150 to 350 g were used as donors and recipients (n = 12). The left common carotid and left pulmonary arteries were anastomosed to the femoral artery and vein in an end-to-end fashion, respectively. Improved modifications included the use of hemostatic vessel clips, heparinization of both donor and recipient, a ventricular prolene stay-suture for secure graft placement, and transfemoral echocardiography (TFE). Total operative time averaged 61 +/- 12 minutes.Femoral accessory transplanted hearts (FATHs) allowed easier pulse palpation and access for TFE versus previously described cervical and intra-abdominal models. This modification allows precise detection of acute graft rejection (AGR) and is defined as absent ventricular contraction in the presence of anastomostic patency.Our new modified technique for heterotopic femoral heart transplantation in rats is a relatively easily learned and reproduced procedure that allows superior allograft access for palpation and improved echocardiographic assessment. Femoral heterotopic heart transplantation remains an effective model for allograft transplantation study.