OBJECTIVES To evaluate the competing pro-haemorrhagic contribution of acquired von Willebrand (vW) disease and antithrombotic therapy in patients implanted with continuous-flow left ventricular assist devices (LVADs). METHODS We compared the extent of vW factor (vWf) degradation [vWf antigen (vWf:Ag)] and a decrease of functional activity of large vWf multimers [vWf collagen binding (vWf:CB)] in LVAD patients who did and did not suffer from bleeding. Data were measured pre-implant, at short-term (t1: <3 months) and long-term (t2: >12 months) follow-up. The occurrence of primary bleeding events, as well as bleeding recurrence, was correlated with patient-specific vWf profile and antithrombotic regimen. Indeed, patients were discharged on warfarin (international normalized ratio: 2–2.5) and aspirin, with the latter withhold after a first bleeding episode. RESULTS Fifty-three patients were enrolled. The median follow-up was 324 (226–468) days. We recorded 25 primary bleeding events (47% of patients). All primary events occurred in patients on warfarin and aspirin. Both vWf:Ag and vWf:CB decreased significantly post-implant (P = 0.0003 and P < 0.0001), and patients showing pathological vWf:CB/vWf:Ag ratio (<0.7) increased progressively over the time of support (pre-implant = 26%, t1 = 58%, t2 = 74%; P < 0.0001). Of note, activity of large vWf multimers of bleeders was significantly lower at t2 with respect to non-bleeders (vWf:CB: 61 (36–115) vs 100 (68–121), P = 0.04; vWf:CB/vWf:Ag ratio: 0.36 (0.26–0.61) vs 0.58 (0.33–0.96), P = 0.04). Despite these marked differences in the vWf profile, following aspirin discontinuation only 3 patients had bleeding recurrence. CONCLUSIONS Aspirin contributes significantly to haemorrhagic events in the background of acquired vW disease; its discontinuation significantly reduces bleeding recurrence. Clinical trial registration https://clinicaltrials.gov/ct2/show/NCT03255928; ClinicalTrials.gov Identifier: NCT03255928.

中文翻译：

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连续流动左心室辅助装置患者出血：获得性血管性血友病或抗血栓药物？

目的 评价获得性血管性血友病 (vW) 疾病和抗血栓治疗在植入连续流动左心室辅助装置 (LVAD) 的患者中的竞争性促出血贡献。方从出血。数据是在植入前、短期（t1：＜3 个月）和长期（t2：＞12 个月）随访中测量的。原发性出血事件的发生以及出血复发与患者特异性 vWf 谱和抗血栓治疗方案相关。事实上，患者出院时服用华法林（国际标准化比率：2-2.5）和阿司匹林，后者在第一次出血后扣留。结果 53 名患者入组。中位随访时间为 324 (226-468) 天。我们记录了 25 起原发性出血事件（47% 的患者）。所有主要事件均发生在服用华法林和阿司匹林的患者身上。植入后 vWf:Ag 和 vWf:CB 均显着下降（P = 0.0003 和 P < 0.0001），显示病理性 vWf:CB/vWf:Ag 比值（<0.7）的患者在植入后逐渐增加（前-植入物 = 26%，t1 = 58%，t2 = 74%；P < 0.0001)。值得注意的是，与非出血者相比，出血者的大 vWf 多聚体的活性在 t2 时显着降低（vWf：CB：61（36-115）对 100（68-121），P = 0.04；vWf：CB/vWf： Ag 比率：0.36 (0.26–0.61) vs 0.58 (0.33–0.96)，P = 0.04)。尽管 vWf 配置文件存在这些显着差异，在阿司匹林停药后，只有 3 名患者出现出血复发。结论 阿司匹林对获得性 vW 疾病背景下的出血事件有显着影响；它的停药显着减少了出血复发。临床试验注册 https://clinicaltrials.gov/ct2/show/NCT03255928；ClinicalTrials.gov 标识符：NCT03255928。