Background Mechanical thrombectomy (MT) has become an increasingly popular approach in treatment of pulmonary embolism (PE). Blood loss from aspiration is common during this procedure and can potentially limit clot extraction. A blood return system designed to be used during MT was introduced in January 2022; however, there is limited data demonstrating if its use has impacted mortality or need for blood transfusion in patients treated with MT. Purpose The aim of this study is to assess if there is a difference in outcomes amongst patients with acute PE that underwent MT with a blood return system vs. those that underwent MT without one. We hypothesize that MT with a blood return system will reduce mortality and need for post-procedure blood transfusions. Methods A large retrospective, multicentre database was used to identify patients diagnosed with PE that underwent MT. Patients were subsequently divided into two groups: 1) After and including January 2022, which was after the implementation of a blood return system vs. 2) Before January 2022, which was prior to the implementation of a blood return system. Student’s t-test was performed to compare baseline characteristics between the two cohorts. Propensity matching was performed based on relevant comorbidities and severity of PE estimated by PESI score parameters. Kaplan Meier curves were calculated to compare 30-day post-procedure mortality and need for blood transfusion. Results Patients that underwent MT after implementation of a blood return system (n= 2511) and before implementation of a blood return system (n= 2755) were propensity matched yielding 1915 patients per cohort. MT after implementation of a blood return system was associated with a decreased 30-day mortality compared to MT before implementation (6.99% vs 11.77% HR=0.602; 95% CI [0.486, 0.746], log-rank p<0.0001). Additionally, MT after implementation of a blood return system was associated with a decreased need for blood transfusion (7.52% vs 10.38%; HR=0.717; 95% CI [0.572, 0.898], log-rank p=0.0034). Conclusion MT after implementation of a blood return system was associated with a decreased risk of 30-day mortality and a lower likelihood of requiring blood transfusion when compared to MT prior to implementation of a blood return system.

中文翻译：

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血液回流系统对急性肺栓塞治疗机械血栓切除术的影响：一项比较 30 天死亡率和输血需求的回顾性队列研究


背景 机械血栓切除术 （MT） 已成为治疗肺栓塞 （PE） 的一种越来越流行的方法。在此过程中，误吸引起的失血很常见，并且可能会限制凝块的提取。2022 年 1 月推出了专为 MT 期间使用的血液回收系统;然而，有限的数据表明其使用是否影响了接受 MT 治疗的患者的死亡率或输血需求。目的 本研究的目的是评估接受血液回流系统 MT 的急性 PE 患者与没有回血系统接受 MT 的患者之间的结果是否存在差异。我们假设带有血液回流系统的 MT 将降低死亡率和术后输血需求。方法 使用一个大型回顾性、多中心数据库来确定被诊断为接受 MT 的 PE 患者。患者随后分为两组：1） 2022 年 1 月之后，即实施血液回流系统之后 vs. 2） 2022 年 1 月之前，即实施血液回流系统之前。进行学生 t 检验以比较两个队列之间的基线特征。根据 PESI 评分参数估计的 PE 的相关合并症和严重程度进行倾向匹配。计算 Kaplan Meier 曲线以比较术后 30 天死亡率和输血需求。结果 在实施血液回流系统 （n= 2511） 和实施血液回流系统 （n= 2755） 之前接受 MT 的患者具有倾向匹配，每个队列产生 1915 名患者。与实施前 MT 相比，实施血液回收系统后的 MT 与 30 天死亡率降低相关 （6.99% vs 11.77% HR=0.602;95% CI [0.486， 0.746]，对数秩 p<0.0001）。此外，实施血液回收系统后的 MT 与输血需求减少相关 （7.52% vs 10.38%;HR=0.717;95% CI [0.572， 0.898]，对数秩 p=0.0034）。结论 与实施血液回流系统之前的 MT 相比，实施血液回流系统后的 MT 与 30 天死亡风险降低和需要输血的可能性降低相关。