Hakim M G, Gill S S
Willis-Knighton Medical Center, Shreveport, LA 71103.
J La State Med Soc. 1993 May;145(5):233-40.
Heart transplantation has become an established therapeutic option for some patients with end stage heart failure. The technique of heart transplantation involves excision of the diseased heart leaving behind cuffs of the right and left atria, pulmonary artery and aorta, which are subsequently attached to their counterparts in the procured donor heart. In most cases donor and recipient operations are carried out in two different hospitals which can be hundreds of miles apart. Careful coordination and timing of the donor and recipient operations is fundamental to keep the ischemic time (ie, the time taken to remove the donor heart, transport to the transplant center and implant in the recipient) to a minimum. Ischemic time longer than 4 hours carries a significantly higher operative mortality. Preservation of the donor heart during the period of ischemia is achieved using a potassium based cardioplegic solution which arrests the heart in diastole, and is supplemented with topical cooling to keep the myocardial temperature at 4 degrees C. Due to cardiac denervation and impaired ability to respond to high filling pressures, maintaining a fast heart rate is essential to maximize cardiac output during the early postoperative period. High pulmonary vascular resistance can occur postoperatively and can result in failure of the donor heart. This may require the use of vasodilators and mechanical right heart assistance. In addition to the use of immunosuppressive agents to prevent rejection of the donor heart, careful attention should be given to renal function and to prophylaxis against infection. The overall 30-day survival (ie, operative survival) currently exceeds 95%.
心脏移植已成为一些终末期心力衰竭患者既定的治疗选择。心脏移植技术包括切除患病心脏，留下左右心房、肺动脉和主动脉的袖口组织，随后将这些组织与获取的供体心脏的相应部位相连。在大多数情况下，供体和受体的手术在相距数百英里的两家不同医院进行。供体和受体手术的仔细协调和时间安排对于将缺血时间（即切除供体心脏、运输到移植中心并植入受体所需的时间）降至最低至关重要。缺血时间超过4小时会带来显著更高的手术死亡率。在缺血期间，使用基于钾的心脏停搏液来保存供体心脏，该溶液可使心脏停搏于舒张期，并辅以局部降温以使心肌温度保持在4摄氏度。由于心脏去神经支配以及对高充盈压反应能力受损，术后早期维持快速心率对于使心输出量最大化至关重要。术后可能会出现高肺血管阻力，并可能导致供体心脏衰竭。这可能需要使用血管扩张剂和机械性右心辅助。除了使用免疫抑制剂来防止供体心脏排斥外，还应密切关注肾功能并预防感染。目前30天生存率（即手术生存率）超过95%。
