Tsau P H, Arabía F A, Toporoff B, Paramesh V, Sethi G K, Copeland J G
Section of Cardiovascular and Thoracic Surgery, University of Arizona Health Science Center, Tucson 85724-5071, USA.
ASAIO J. 1998 Sep-Oct;44(5):M634-7. doi: 10.1097/00002480-199809000-00067.
Patients who are bridged-to-transplantation with mechanical support have a high incidence of pretransplant sensitization defined by panel reactive antibody (PRA) titers greater than 10. Risk factors for positive PRA in patients with assist devices were investigated. From 1993 to 1997, 17 patients underwent implant surgery with CardioWest C-70 total artificial hearts (TAHs; CardioWest Technologies, Inc., Tucson, AZ), and 13 with Novacor left ventricular assist systems (LVASs; Baxter Healthcare, Novacor Division, Oakland, CA) for bridge-to-transplantation at this institution. Two patients died during implantation of the assist devices. Of the remaining 28 patients, four (14%) were women (3 with TAHs and 1 with an LVAS). All four women (100%) had a positive PRA, whereas only two of the 24 men (8%) had positive PRA (p < 0.0001). The transfusion histories of these patients were reviewed. Using chi-squared analysis (alpha = 0.05), the PRA levels were independent of transfusion of packed red blood cells and fresh frozen plasma. There was an association, however, between platelet transfusions and PRA levels. The times on device awaiting cardiac transplantation were also compared between the PRA positive and PRA negative groups. The average time to transplantation for PRA positive patients was 116 days, whereas the average waiting time for the PRA negative patients was 55 days (p = 0.05). Based on these data, a female patient with consistently positive PRA (93%) after TAH implantation underwent a transplant on post implant day 25 despite a positive lymphocytotoxic crossmatch with the donor. She was treated with plasmapheresis during cardiopulmonary bypass at the time of transplantation, and with four further treatments post transplant. As of this writing, she is alive and well on our standard triple immunotherapy. Therefore, women who are bridged-to-transplantation with assist devices are at risk for positive PRA. It is recommended that patients who are bridged-to-transplantation with assist devices and have high PRA levels be treated with perioperative plasmapheresis. With this aggressive approach, it may no longer be necessary to keep patients on mechanical support for prolonged periods, but possible to perform transplants as soon as suitable donors become available.
接受机械支持过渡到移植的患者，移植前致敏发生率较高，其定义为群体反应性抗体（PRA）滴度大于10。对使用辅助装置的患者PRA呈阳性的危险因素进行了研究。1993年至1997年，本机构有17例患者接受了CardioWest C - 70型全人工心脏（TAH；CardioWest Technologies公司，图森，亚利桑那州）植入手术，13例接受了Novacor左心室辅助系统（LVAS；百特医疗保健公司，Novacor分部，奥克兰，加利福尼亚州）植入手术以过渡到移植。2例患者在辅助装置植入过程中死亡。在其余28例患者中，4例（14%）为女性（3例使用TAH，1例使用LVAS）。所有4例女性（100%）PRA呈阳性，而24例男性中只有2例（8%）PRA呈阳性（p < 0.0001）。回顾了这些患者的输血史。采用卡方分析（α = 0.05），PRA水平与浓缩红细胞和新鲜冰冻血浆的输注无关。然而，血小板输注与PRA水平之间存在关联。还比较了PRA阳性组和PRA阴性组等待心脏移植时使用装置的时间。PRA阳性患者的平均移植时间为116天，而PRA阴性患者的平均等待时间为55天（p = 0.05）。基于这些数据，1例TAH植入后PRA持续呈阳性（93%）的女性患者，尽管与供体淋巴细胞毒性交叉配型呈阳性，但在植入后第25天接受了移植。移植时在体外循环期间对她进行了血浆置换治疗，移植后又进行了4次治疗。截至撰写本文时，她在接受标准三联免疫治疗下情况良好且存活。因此，使用辅助装置过渡到移植的女性患者有PRA呈阳性的风险。建议对使用辅助装置过渡到移植且PRA水平高的患者在围手术期进行血浆置换治疗。采用这种积极的方法，可能不再需要让患者长时间依赖机械支持，而是在合适的供体出现后尽快进行移植。
