Division of Cardiology, Department of Medicine, Duke University Medical Center, Durham, NC (L.K.T.).
Division of Cardiology, Department of Medicine (M.A.F., A.R.G., R.G., S.W.R., F.L., V.K.T.), Columbia University College of Physicians and Surgeons, New York, NY.
Circulation. 2019 Aug 6;140(6):459-469. doi: 10.1161/CIRCULATIONAHA.118.036932. Epub 2019 Jun 17.
Bridge to transplantation (BTT) with left ventricular assist devices (LVADs) is a mainstay of therapy for heart failure in patients awaiting heart transplantation (HT). Criteria for HT listing do not differ between patients medically managed and those mechanically bridged to HT. The objectives of the present study were to evaluate the impact of BTT with LVAD on posttransplantation survival, to describe differences in causes of 1-year mortality in medically and mechanically bridged patients, and to evaluate differences in risk factors for 1-year mortality between those with and those without LVAD at the time of HT.
Using the United Network of Organ Sharing database, we identified 5486 adult, single-organ HT recipients transplanted between 2008 and 2015. Patients were propensity matched for likelihood of LVAD at the time of HT. Kaplan-Meier survival estimates were used to assess the impact of BTT on 1- and 5-year mortality. Logistic regression analysis was used to evaluate the odds ratio of 1-year mortality for patients BTT with LVAD compared with those with medical management across clinically significant variables at various thresholds.
Early mortality was higher in mechanically bridged patients: 9.5% versus 7.2% mortality at 1 year (P<0.001). BTT patients incurred an increased risk of 1-year mortality with an estimated glomerular filtration rate of 40 to 60 mL·min·1.73 m (odds ratio, 1.69; P=0.003) and <40 mL·min·1.73 m (odds ratio, 2.16; P=0.005). A similar trend was seen in patients with a body mass index of 25 to 30 kg/m (odds ratio, 1.88; P=0.024) and >30 kg/m (odds ratio, 2.11; P<0.001). When patients were stratified by BTT status and the presence of risk factors, including age >60 years, estimated glomerular filtration rate <40 mL·min·1.73 m, and body mass index >30 kg/m, there were significant differences in 1-year mortality between medium- and high-risk medically and mechanically bridged patients, with 1-year mortality in high-risk BTT patients at 17.6% compared with 10.4% in high-risk medically managed patients.
Bridge to HT with LVAD, although necessary because of organ scarcity and capable of improving wait list survival, confers a significantly higher risk of early posttransplantation mortality. Patients bridged with mechanical support may require more careful consideration for transplant eligibility after LVAD placement.
左心室辅助装置(LVAD)桥接移植(BTT)是心力衰竭患者心脏移植(HT)等待治疗的主要方法。HT 患者的 HT 列入标准在接受药物治疗的患者和机械桥接至 HT 的患者之间没有差异。本研究的目的是评估 LVAD 桥接对移植后生存率的影响,描述药物治疗和机械桥接患者 1 年死亡率的原因差异,并评估 HT 时具有和不具有 LVAD 的患者 1 年死亡率的危险因素差异。
利用美国器官共享网络数据库,我们确定了 2008 年至 2015 年间接受单器官 HT 的 5486 名成年患者。根据 HT 时 LVAD 的可能性对患者进行倾向匹配。使用 Kaplan-Meier 生存估计评估 BTT 对 1 年和 5 年死亡率的影响。使用逻辑回归分析评估与接受药物治疗的患者相比,LVAD 桥接患者在不同阈值的临床重要变量下的 1 年死亡率的比值比。
机械桥接患者的早期死亡率更高:1 年时死亡率为 9.5%,而 7.2%(P<0.001)。BTT 患者的估计肾小球滤过率为 40 至 60 ml·min·1.73 m(比值比,1.69;P=0.003)和<40 ml·min·1.73 m(比值比,2.16;P=0.005)时,1 年死亡率的风险增加。在体重指数为 25 至 30 kg/m(比值比,1.88;P=0.024)和>30 kg/m(比值比,2.11;P<0.001)的患者中也观察到类似的趋势。当根据 BTT 状态和存在的危险因素(包括年龄>60 岁、估计肾小球滤过率<40 ml·min·1.73 m 和体重指数>30 kg/m)对患者进行分层时,在中危和高危药物治疗和机械桥接患者之间,1 年死亡率存在显著差异,高危 BTT 患者的 1 年死亡率为 17.6%,而高危药物治疗患者的 1 年死亡率为 10.4%。
LVAD 桥接 HT 虽然由于器官短缺而有必要,并且能够提高等待名单上的生存率,但会显著增加移植后早期死亡率的风险。接受机械支持桥接的患者在 LVAD 放置后可能需要更仔细地考虑移植资格。