Department of Cardiac Surgery, The University of Tokyo.
Department of Cardiac Surgery, The University of Tokyo;
J Vis Exp. 2023 Jun 2(196). doi: 10.3791/64813.
Over the past 50 years, many researchers have reported heterotopic abdominal heart transplantation in mice and rats, with some variations in the surgical technique. Modifying the transplantation procedure to strengthen the myocardial protection could prolong the ischemia time while preserving the donor's cardiac function. This technique's key points are as follows: transecting the donor's abdominal aorta before harvesting to unload the donor's heart; perfusing the donor's coronary arteries with a cold cardioplegic solution; and topical cooling of the donor's heart during the anastomosis procedure. Consequently, since this procedure prolongs the acceptable ischemia time, beginners can easily perform it and achieve a high success rate. Moreover, a new aortic regurgitation (AR) model was established in this work using a technique different from the existing one, which is created by inserting a catheter from the right carotid artery and puncturing the native aortic valve under continuous echocardiographic guidance. A heterotopic abdominal heart transplantation was performed using the novel AR model. In the protocol, after the donor's heart is harvested, a stiff guidewire is inserted into the donor's brachiocephalic artery and advanced toward the aortic root. The aortic valve is punctured by pushing the guidewire further even after the resistance is felt, thus inducing AR. It is easier to damage the aortic valve using this method than with the procedure described in the conventional AR model. Additionally, this novel AR model does not contribute to the recipient's circulation; therefore, this method is expected to produce a more severe AR model than the conventional procedure.
在过去的 50 年中，许多研究人员已经报道了在小鼠和大鼠中进行异位腹部心脏移植，手术技术有所不同。通过修改移植程序来加强心肌保护，可以延长缺血时间，同时保持供体的心脏功能。该技术的关键点如下：在收获供体心脏之前切断供体的腹主动脉以卸载供体心脏；用冷心脏停搏液灌注供体的冠状动脉；在吻合过程中对供体心脏进行局部冷却。因此，由于该程序延长了可接受的缺血时间，初学者可以轻松进行操作并获得高成功率。此外，本工作采用不同于现有技术的技术建立了一种新的主动脉瓣反流（AR）模型，该技术通过从右侧颈动脉插入导管并在连续超声心动图引导下穿刺天然主动脉瓣来实现。使用新型 AR 模型进行异位腹部心脏移植。在方案中，在收获供体心脏后，将一根硬导丝插入供体的头臂动脉，并向主动脉根部推进。即使感觉到阻力，也进一步推动导丝穿刺主动脉瓣，从而引起 AR。与传统 AR 模型中描述的程序相比，使用这种方法更容易损坏主动脉瓣。此外，这种新型 AR 模型不会对受体循环造成影响；因此，与传统方法相比，这种方法预计会产生更严重的 AR 模型。
