Division of Vascular and Endovascular Surgery, Massachusetts General Hospital, Boston, Mass.
Division of Vascular and Endovascular Surgery, Massachusetts General Hospital, Boston, Mass.
J Vasc Surg Venous Lymphat Disord. 2018 Jan;6(1):109-117. doi: 10.1016/j.jvsv.2017.08.016. Epub 2017 Oct 31.
Acute superficial vein thrombosis (SVT) of the axial veins, such as the great saphenous vein (GSV), is a common clinical condition that carries with it significant risk of propagation of thrombus, recurrence, and, most concerning, subsequent venous thromboembolism (VTE). Conservative therapy with nonsteroidal anti-inflammatory medication and heat does not prevent extension of thrombus or protect against recurrent or future VTE in patients with extensive SVT (thrombotic segment of at least 5 cm in length). To prevent future thromboembolic events, anticoagulation has become the treatment of choice for extensive acute SVT in the GSV. In spite of this, the dose and duration of anticoagulation in the treatment of SVT vary widely. This review summarizes the evidence from large prospective, randomized clinical trials on the treatment of SVT with anticoagulation (vs placebo or different doses and durations of anticoagulation) with respect to the outcome measures of thrombus extension, SVT recurrence, and future VTE.
A systematic search was performed using the MEDLINE database to identify all prospective, randomized controlled trials of treatment with anticoagulation in patients with SVT in the GSV. Six prospective, randomized trials were identified that met the inclusion criteria and were reviewed in detail.
Treatment of acute SVT was most commonly managed in an outpatient setting using either low-molecular-weight heparin (LMWH) in four studies or, alternatively, a factor Xa inhibitor in one large multicenter trial. LMWH was associated with a lower rate of thrombus extension and subsequent recurrence, especially when an intermediate dose (defined as a dose between prophylactic and therapeutic doses) was used for a period of 30 days. The full effect of treatment with LMWH on the risk of subsequent VTE remains unclear, as do the optimal dose and duration of this drug. Prophylactic doses of fondaparinux, a factor Xa inhibitor, were found to be beneficial in reducing the rate of thrombus extension and recurrence as well as in reducing the risk of subsequent VTE both during treatment and after cessation of anticoagulation in the short term.
These data suggest that treatment of acute SVT of the GSV with anticoagulation, at doses below therapeutic levels, does offer the benefit of decreased risk of thrombus propagation, recurrence, and, at least in one large randomized clinical trial, subsequent VTE. Future studies to refine optimal dose and duration of anticoagulation to lower the rate of subsequent thromboembolic events and SVT recurrence are needed.
急性浅静脉血栓形成（SVT），如大隐静脉（GSV），是一种常见的临床病症，存在血栓延伸、复发以及更令人担忧的静脉血栓栓塞症（VTE）的显著风险。对于广泛的 SVT（血栓段至少 5 厘米长）患者，非甾体抗炎药和热疗等保守治疗并不能预防血栓延伸，也不能预防复发或未来的 VTE。为了预防未来的血栓栓塞事件，抗凝治疗已成为 GSV 中广泛急性 SVT 的治疗选择。尽管如此，SVT 治疗中抗凝的剂量和持续时间差异很大。本综述总结了大样本前瞻性随机临床试验中关于抗凝治疗 SVT（与安慰剂或不同剂量和持续时间的抗凝治疗相比）的血栓延伸、SVT 复发和未来 VTE 结局指标的证据。
使用 MEDLINE 数据库进行系统检索，以确定所有关于 GSV 中 SVT 抗凝治疗的前瞻性随机对照试验。确定了 6 项符合纳入标准的前瞻性随机试验，并进行了详细审查。
急性 SVT 的治疗主要在门诊进行，4 项研究中使用低分子肝素（LMWH），1 项大型多中心试验中使用因子 Xa 抑制剂。LMWH 与血栓延伸和随后的复发率较低相关，尤其是当使用中等剂量（定义为预防剂量和治疗剂量之间的剂量）持续 30 天时。LMWH 治疗对随后 VTE 风险的完全影响仍不清楚，这种药物的最佳剂量和持续时间也不清楚。因子 Xa 抑制剂磺达肝素的预防剂量被发现有利于降低血栓延伸和复发的发生率，并降低短期治疗和停止抗凝后的随后 VTE 风险。
这些数据表明，在低于治疗水平的剂量下，抗凝治疗 GSV 急性 SVT 确实可以降低血栓延伸、复发以及至少在一项大型随机临床试验中随后 VTE 的风险。需要进一步研究以确定最佳剂量和持续时间的抗凝治疗，以降低随后的血栓栓塞事件和 SVT 复发的发生率。
