NEJM：起搏器手术患者使用华法林持续治疗可显著减少血肿风险

长期口服抗凝药物治疗的患者在起搏器植入手术前抗凝药物的使用方法一直是临床关注的问题。一般认为需在植入手术之前停用口服华法林，并改用桥接抗凝治疗肝素皮下注射。近期进行的Bruise对照研究，主要比较了肝素桥接治疗与口服华法林治疗在术后血肿并发症方面的差异。

Bruise对照试验研究者介绍说，对于中高度血栓风险的患者而言，起搏器或除颤器（ICD）置入手术有使用华法林持续治疗效果可能优于肝素。

加拿大渥太华大学心脏研究所的David Birnie博士与其同事报道称，随机分组接受持续口服抗凝治疗的343例患者中，仅发现有3.5%发展为临床特征明显的装置相关的血肿，与之相比，在提前3天就进行肝素桥接治疗的338例患者中，则有16%出现血肿。

与桥接治疗相比，华法林持续治疗有更低的血肿相关住院率（1.2 vs 4.7%）以及血肿相关的抗凝治疗停药（3.2 vs 14.2%）和需要行血肿清除术（0.6 vs 2.7%）。由于发生血肿的患者与没有并发症的患者相比，遭受更多的痛苦且生活质量更差，研究者指出，“这些结果表明起搏器或ICD手术期间应该更多使用华法林而不是使用肝素桥接治疗，至少对于入组我们试验的患者是这样的。”

所有患者的栓塞年发生率在5%以上。事件发生率具有组间相似性。华法林持续治疗组有1例卒中和1例短暂缺血发作，肝素桥接组有1例心脏填塞和1例心肌梗塞。文章作者Vidal Essebag博士在述评中强调，华法林持续治疗引起的血肿风险的减少或与直觉不符。他假设道：“其中一项解释是抗凝治疗应激试验的概念。如果患者在完全抗凝的前提下手术，那么伤口愈合前任何过量流血的事件都可被及时发现并及时治疗。”“然而，当在肝素桥接前提下予以手术时，上述流血事件可能变为潜在的，只有当予以术后完全抗凝时它都会被发现。”

Pacemaker or defibrillator surgery without interruption of anticoagulation.
BACKGROUND
Many patients requiring pacemaker or implantable cardioverter-defibrillator (ICD) surgery are taking warfarin. For patients at high risk for thromboembolic events, guidelines recommend bridging therapy with heparin; however, case series suggest that it may be safe to perform surgery without interrupting warfarin treatment. There have been few results from clinical trials to support the safety and efficacy of this approach.
METHODS
We randomly assigned patients with an annual risk of thromboembolic events of 5% or more to continued warfarin treatment or to bridging therapy with heparin. The primary outcome was clinically significant device-pocket hematoma, which was defined as device-pocket hematoma that necessitated prolonged hospitalization, interruption of anticoagulation therapy, or further surgery (e.g., hematoma evacuation).
RESULTS
The data and safety monitoring board recommended termination of the trial after the second prespecified interim analysis. Clinically significant device-pocket hematoma occurred in 12 of 343 patients (3.5%) in the continued-warfarin group, as compared with 54 of 338 (16.0%) in the heparin-bridging group (relative risk, 0.19; 95% confidence interval, 0.10 to 0.36; P<0.001). Major surgical and thromboembolic complications were rare and did not differ significantly between the study groups. They included one episode of cardiac tamponade and one myocardial infarction in the heparin-bridging group and one stroke and one transient ischemic attack in the continued-warfarin group.
CONCLUSIONS
As compared with bridging therapy with heparin, a strategy of continued warfarin treatment at the time of pacemaker or ICD surgery markedly reduced the incidence of clinically significant device-pocket hematoma. (Funded by the Canadian Institutes of Health Research and the Ministry of Health and Long-Term Care of Ontario; BRUISE CONTROL ClinicalTrials.gov number, NCT00800137.).