Cedars-Sinai Heart Institute, Los Angeles, CA, USA.
Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
J Thromb Haemost. 2017 Aug;15(8):1620-1624. doi: 10.1111/jth.13753. Epub 2017 Jul 5.
Essentials Bleeding is a major source of morbidity during mechanical circulatory support. von Willebrand factor (VWF) multimer loss may contribute to bleeding. Different patterns of VWF multimer loss were seen with the two device types. This is the first report of total artificial heart associated VWF multimer loss.
Background Bleeding remains a challenge during mechanical circulatory support and underlying mechanisms are incompletely understood. Functional von Willebrand factor (VWF) impairment because of loss of high-molecular-weight multimers (MWMs) produces acquired von Willebrand disease (VWD) after left ventricular assist device (LVAD). Little is known about VWF multimers with total artificial hearts (TAHs). Here, VWF profiles with LVADs and TAHs are compared using a VWD panel. Methods VWD evaluations for patients with LVAD or TAH (2013-14) were retrospectively analyzed and included: VWF activity (ristocetin cofactor, VWF:RCo), VWF antigen (VWF:Ag), ratio of VWF:RCo to VWF:Ag, and quantitative VWF multimeric analysis. Results Twelve patients with LVADs and 12 with TAHs underwent VWD evaluation. All had either normal (47.8%) or elevated (52.2%) VWF:RCo, normal (26.1%) or elevated (73.9%) VWF:Ag and 50.0% were disproportional (ratio ≤ 0.7). Multimeric analysis showed abnormal patterns in all patients with LVADs: seven with high MWM loss; five with highest MWM loss. With TAH, 10/12 patients had abnormal patterns: all with highest MWM loss. High MWM loss correlated with presence of LVAD and highest MWM loss with TAH. Increased low MWMs were detected in 22/24. Conclusion Using VWF multimeric analysis, abnormalities after LVAD or TAH were detected that would be missed with measurements of VWF level alone: loss of high MWM predominantly in LVAD, loss of highest MWM in TAH, and elevated levels of low MWM in both. This is the first study to describe TAH-associated highest MWM loss, which may contribute to bleeding.
机械循环支持期间出血是发病率的主要来源。血管性血友病因子（VWF）多聚体丢失可能导致出血。两种设备类型的 VWF 多聚体丢失模式不同。这是首例全人工心脏相关 VWF 多聚体丢失的报告。
机械循环支持期间仍然存在出血挑战，其潜在机制尚不完全清楚。由于左心室辅助装置（LVAD）导致高分子量多聚体（MWM）丢失而导致的功能性血管性血友病因子（VWF）功能障碍可导致获得性血管性血友病（VWD）。关于全人工心脏（TAH）的 VWF 多聚体知之甚少。在此，使用 VWD 面板比较 LVAD 和 TAH 患者的 VWF 谱。
对 2013-2014 年接受 LVAD 或 TAH 的患者进行 VWD 评估，并进行回顾性分析，包括：VWF 活性（瑞斯托霉素辅因子，VWF：RCo）、VWF 抗原（VWF：Ag）、VWF：RCo 与 VWF：Ag 的比值和定量 VWF 多聚体分析。
12 例 LVAD 患者和 12 例 TAH 患者接受了 VWD 评估。所有患者的 VWF：RCo 均正常（47.8%）或升高（52.2%），VWF：Ag 正常（26.1%）或升高（73.9%），50.0%的患者比例不成比例（比值≤0.7）。多聚体分析显示，所有 LVAD 患者的模式均异常：7 例有高 MWM 丢失；5 例有最高 MWM 丢失。在 TAH 中，10/12 例患者的模式异常：均有最高 MWM 丢失。高 MWM 丢失与 LVAD 存在相关，最高 MWM 丢失与 TAH 相关。24 例中有 22 例检测到低 MWMs 升高。
使用 VWF 多聚体分析检测到 LVAD 或 TAH 后会出现异常，而仅测量 VWF 水平会错过这些异常：LVAD 中主要丢失高 MWM，TAH 中丢失最高 MWM，两者均升高低 MWMs。这是首例描述 TAH 相关最高 MWM 丢失的研究，可能导致出血。
