Holman W L, Murrah C P, Ferguson E R, Bourge R C, McGiffin D C, Kirklin J K
Department of Cardiothoracic Surgery, University of Alabama at Birmingham 35294, USA.
Ann Thorac Surg. 1996 Jan;61(1):366-71; discussion 372-3. doi: 10.1016/0003-4975(95)01021-1.
The University of Alabama at Birmingham experience with investigational ventricular assist devices (VADs) used as a bridge to transplantation has increased over the past several years; it now includes 27 VAD implantations with 13 VAD runs lasting for extended periods (ie, > 30 days). A review of complications experienced by patients during extended VAD runs is warranted before the further development and testing of chronically implanted mechanical circulatory support devices.
This study focuses on the infectious complications of extended VAD support; it includes 13 patients who were supported by either a Thoratec or HeartMate VAD for longer than 30 days pending cardiac transplantation. Infection was defined as any positive culture. The infections were classed according to site and severity as follows: class I were patient-related non-blood-borne infections, class II were blood-borne infections, class III were VAD percutaneous site infections, and class IV were infections of the blood-contacting surfaces or intracorporeal components of the VAD.
The 8 Thoratec and 5 HeartMate patients were supported for a total of 1,648 days with a range of 33 to 279 days per patient. Every patient had at least one infection; however, there were 6 patients who had no class II or IV infections during the period of support. One of these 6 patients died of a stroke, whereas the other 5 patients survived VAD support. No trends were identified for a change in the incidence of bacterial compared with fungal infections during the course of VAD support. There was no trend for a greater number of infections in patients who died during VAD support compared with those who survived. Neither class II nor IV infections precluded transplantation. Three patients died during VAD support; 1 died as a direct consequence of fungal infection. Eight patients received transplants. One patient had an unanticipated recovery of cardiac function and the VAD was removed. Support in 1 patient is ongoing.
Infection during VAD support pending cardiac transplantation is an important cause of morbidity and mortality in patients maintained for longer than 30 days by circulatory assist. Infectious complications will probably be a prominent component of the risk associated with the use of chronically implanted mechanical circulatory assist devices and will likely have an important effect on the quality of life experienced by these patients.
在过去几年中，阿拉巴马大学伯明翰分校使用试验性心室辅助装置（VAD）作为移植桥梁的经验有所增加；目前已包括27例VAD植入手术，其中13例VAD运行持续较长时间（即>30天）。在长期植入式机械循环支持装置的进一步研发和测试之前，有必要回顾一下患者在VAD长期运行期间所经历的并发症。
本研究聚焦于VAD长期支持的感染并发症；纳入了13例在等待心脏移植期间接受Thoratec或HeartMate VAD支持超过30天的患者。感染定义为任何阳性培养结果。感染根据部位和严重程度分类如下：I类为与患者相关的非血源性感染，II类为血源性感染，III类为VAD经皮部位感染，IV类为VAD血液接触表面或体内组件感染。
8例使用Thoratec和5例使用HeartMate的患者共接受了1648天的支持，每位患者的支持时间为33至279天不等。每位患者至少发生过一次感染；然而，有6例患者在支持期间未发生II类或IV类感染。这6例患者中有1例死于中风，而其他5例患者在VAD支持下存活。在VAD支持过程中，未发现细菌感染与真菌感染发生率变化的趋势。在VAD支持期间死亡的患者与存活患者相比，感染数量没有增加的趋势。II类和IV类感染均不排除移植。3例患者在VAD支持期间死亡；1例直接死于真菌感染。8例患者接受了移植。1例患者心脏功能意外恢复，VAD被移除。1例患者的支持仍在进行中。
在等待心脏移植期间进行VAD支持时，感染是接受循环辅助支持超过30天患者发病和死亡的重要原因。感染并发症可能是长期植入式机械循环辅助装置使用风险的一个突出组成部分，并可能对这些患者的生活质量产生重要影响。
