Xie Ashleigh, Phan Kevin, Yan Tristan D
1 The Collaborative Research (CORE) Group, Macquarie University, Sydney, Australia ; 2 Department of Cardiothoracic Surgery, Royal Prince Alfred Hospital, Sydney, Australia.
Ann Cardiothorac Surg. 2014 Nov;3(6):547-56. doi: 10.3978/j.issn.2225-319X.2014.11.01.
Left ventricular assist devices (LVADs) are becoming an increasingly viable alternative therapy for heart failure, either as a bridge to heart transplantation (BTT) or destination therapy (DT). The latter has become increasingly popular in recent years, in the face of a donor organ shortage and a rise in elderly patients ineligible for heart transplants. For these patients in particular, device durability is a key contributor to survival, morbidity, and quality of life. This systematic review aimed to assess the long-term durability of current continuous-flow LVADs.
Six electronic databases were searched from their dates of inception to August 2014 for original studies reporting on patients receiving continuous-flow LVADs. LVAD failure was defined as device malfunction necessitating exchange or explantation, or causing patient mortality. Pooled averages were calculated for outcomes and rates of device failure were reconstructed from digitized graph curves using the software, WebPlotDigitizer v3.3.
Twelve retrospective observational studies with a total of 5,471 patients were included for analysis. The mean duration of LVAD support was 504.7 (range, 303-568) days, and the overall weighted incidence of device failure was 3.9% (range, 1-11.3%). On average, pump thrombosis was the most common cause of device failure (50.5%), followed by lead or cable damage (21.7%), mechanical pump failure (11.6%), device-related infection (11.1%), and surgical complications from implantation (2.5%). Long-term device failure rates at 2-, 6-, 12-, 18- and 24-months post-implantation were 0.5%, 1.8%, 2.9%, 4.5% and 6.5%, respectively.
With the expected rise in LVAD usage for end-stage heart failure, particularly as a DT, the steady minority of patients experiencing device failure is likely to increase. Further investigation is required into the incidence and mechanism of major causes of failure, as well as design improvements that may address these complications. There is currently a lack of guidelines and large randomized studies reporting on the etiology and outcomes of LVAD failure.
左心室辅助装置（LVADs）正日益成为治疗心力衰竭的一种可行替代疗法，可作为心脏移植的过渡治疗（BTT）或终末期治疗（DT）。近年来，面对供体器官短缺以及不符合心脏移植条件的老年患者数量增加的情况，后者越来越受欢迎。对于这些患者而言，装置的耐用性是影响生存、发病率和生活质量的关键因素。本系统评价旨在评估当前连续流LVADs的长期耐用性。
检索了六个电子数据库，从其创建日期至2014年8月，查找关于接受连续流LVADs患者的原始研究。LVAD故障定义为需要更换或取出装置的故障，或导致患者死亡的故障。计算汇总平均值作为结果，并使用WebPlotDigitizer v3.3软件从数字化图形曲线重建装置故障率。
纳入12项回顾性观察研究，共5471例患者进行分析。LVAD支持的平均持续时间为504.7（范围303 - 568）天，装置故障的总体加权发生率为3.9%（范围1 - 11.3%）。平均而言，泵血栓形成是装置故障最常见的原因（50.5%），其次是导线或电缆损坏（21.7%）、机械泵故障（11.6%）、与装置相关的感染（11.1%）以及植入手术并发症（2.5%）。植入后2个月、6个月、12个月、18个月和24个月的长期装置故障率分别为0.5%、1.8%、2.9%、4.5%和6.5%。
随着终末期心力衰竭患者使用LVAD的预期增加，特别是作为终末期治疗，经历装置故障的少数患者数量可能会增加。需要进一步研究主要故障原因的发生率和机制，以及可能解决这些并发症的设计改进。目前缺乏关于LVAD故障的病因和结果的指南及大型随机研究。
