Division of Cardiovascular Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA.
Department of Pathology, University of Utah School of Medicine, Salt Lake City, Utah, USA.
Clin Transplant. 2024 May;38(5):e15330. doi: 10.1111/ctr.15330.
Since the 2018 change in the US adult heart allocation policy, more patients are bridged-to-transplant on temporary mechanical circulatory support (tMCS). Previous studies indicate that durable left ventricular assist devices (LVAD) may lead to allosensitization. The goal of this study was to assess whether tMCS implantation is associated with changes in sensitization.
We included patients evaluated for heart transplants between 2015 and 2022 who had alloantibody measured before and after MCS implantation. Allosensitization was defined as development of new alloantibodies after tMCS implant.
A total of 41 patients received tMCS before transplant. Nine (22.0%) patients developed alloantibodies following tMCS implantation: 3 (12.0%) in the intra-aortic balloon pump group (n = 25), 2 (28.6%) in the microaxial percutaneous LVAD group (n = 7), and 4 (44.4%) in the veno-arterial extra-corporeal membrane oxygenation group (n = 9)-p = .039. Sensitized patients were younger (44.7 ± 11.6 years vs. 54.3 ± 12.5 years, p = .044), were more likely to be sensitized at baseline - 3 of 9 (33.3%) compared to 2 out of 32 (6.3%) (p = .028) and received more transfusions with red blood cells (6 (66.6%) vs. 8 (25%), p = .02) and platelets (6 (66.6%) vs. 5 (15.6%), p = .002). There was no significant difference in tMCS median duration of support (4 [3,15] days vs. 8.5 [5,14.5] days, p = .57). Importantly, out of the 11 patients who received a durable LVAD after tMCS, 5 (45.5%) became sensitized, compared to 4 out of 30 patients (13.3%) who only had tMCS-p = .028.
Our findings suggest that patients bridged-to-transplant with tMCS, without significant blood product transfusions and a subsequent durable LVAD implant, have a low risk of allosensitization. Further studies are needed to confirm our findings and determine whether risk of sensitization varies by type of tMCS and duration of support.
自 2018 年美国成人心脏分配政策改变以来，更多的患者在接受临时机械循环支持（tMCS）的情况下进行移植前过渡。先前的研究表明，耐用的左心室辅助装置（LVAD）可能导致同种异体致敏。本研究的目的是评估 tMCS 植入是否与致敏变化有关。
我们纳入了 2015 年至 2022 年期间接受心脏移植评估的患者，这些患者在接受 MCS 植入前后均进行了同种异体抗体检测。同种异体致敏定义为 tMCS 植入后新的同种异体抗体的发展。
共有 41 例患者在移植前接受了 tMCS。9 例（22.0%）患者在接受 tMCS 植入后出现同种异体抗体：主动脉内球囊泵组 3 例（12.0%，n=25），微轴经皮 LVAD 组 2 例（28.6%，n=7），静脉动脉体外膜肺氧合组 4 例（44.4%，n=9）-p=0.039。致敏患者更年轻（44.7±11.6 岁 vs. 54.3±12.5 岁，p=0.044），在基线时更有可能致敏-9 例中有 3 例（33.3%），而 32 例中有 2 例（6.3%）（p=0.028），并且接受了更多的红细胞（6 例[66.6%]与 8 例[25%]，p=0.02）和血小板（6 例[66.6%]与 5 例[15.6%]，p=0.002）输血。tMCS 中位支持时间（4[3,15]天 vs. 8.5[5,14.5]天，p=0.57）无显著差异。重要的是，在接受 tMCS 后接受耐用型 LVAD 的 11 例患者中，有 5 例（45.5%）致敏，而在仅接受 tMCS 的 30 例患者中，有 4 例（13.3%）致敏-p=0.028。
我们的研究结果表明，接受 tMCS 桥接移植、无显著血液制品输血和随后植入耐用型 LVAD 的患者，同种异体致敏的风险较低。需要进一步的研究来证实我们的发现，并确定致敏的风险是否因 tMCS 的类型和支持时间的不同而不同。
