Agnelli Giancarlo, Becattini Cecilia
Division of Internal and Cardiovascular Medicine, University of Perugia, Via G Dottori 1, Perugia, Italy.
J Thromb Thrombolysis. 2008 Feb;25(1):37-44. doi: 10.1007/s11239-007-0103-z. Epub 2007 Oct 1.
Currently available anticoagulants are effective in reducing the recurrence rate of venous thromboembolism (VTE). However, anticoagulant treatment is associated with an increased risk for bleeding complications. Thus, anticoagulation has to be discontinued when benefit of treatment no longer clearly outweigh its risks. The duration of anticoagulant treatment is currently framed based on the estimated individual risk for recurrent VTE. The incidence of recurrent VTE can be estimated through a two-step decision algorithm. Firstly, the features of the patient (gender), of the initial event (proximal or distal deep vein thrombosis or pulmonary embolism), and the associated conditions (cancer, surgery, etc) provide essential information on the risk for recurrence after anticoagulant treatment discontinuation. Secondly, at time of anticoagulant treatment discontinuation, D: -dimer levels and residual thrombosis have been indicated as predictors of recurrent VTE. Current evidence suggests that the risk of recurrence after stopping therapy is largely determined by whether the acute episode of VTE has been effectively treated and by the patient's intrinsic risk of having a new episode of VTE. All patients with acute VTE should receive oral anticoagulant treatment for three months. At the end of this treatment period, physicians should decide for withdrawal or indefinite anticoagulation. Based on intrinsic patient's risk for recurrent VTE and for bleeding complications and on patient preference, selected patients could be allocated to indefinite treatment with VKA with scheduled periodic re-assessment of the benefit from extending anticoagulation. Alternative strategies for secondary prevention of VTE to be used after conventional anticoagulation are currently under evaluation. Cancer patients should receive low molecular-weight heparin over warfarin in the long-term treatment of VTE. These patients should be considered for extended anticoagulation at least until resolution of underlying disease. The risk for recurrent venous thromboembolism can be estimated through a two-step algorithm. Firstly, the features of the patient (gender), of the initial event (proximal or distal deep vein thrombosis or pulmonary embolism), and the associated conditions (cancer, surgery, etc) are essential to estimate the risk for recurrence after anticoagulant treatment discontinuation. Secondly, a correlation has been shown between D: -dimer levels and residual thrombosis at time of anticoagulant treatment discontinuation and the risk of recurrence. Currently available anticoagulants are effective in reducing the incidence of recurrent venous thromboembolism, but they are associated with an increased risk for bleeding complications. All patients with acute venous thromboembolism should receive oral anticoagulant treatment for three months. At the end of this treatment period physicians should decide for definitive withdrawal or indefinite anticoagulation with scheduled periodic re-assessment of the benefit from extending anticoagulation.
目前可用的抗凝剂在降低静脉血栓栓塞(VTE)复发率方面是有效的。然而,抗凝治疗会增加出血并发症的风险。因此,当治疗益处不再明显超过风险时,必须停止抗凝治疗。目前,抗凝治疗的持续时间是根据个体复发性VTE的估计风险来确定的。复发性VTE的发生率可通过两步决策算法进行估计。首先,患者的特征(性别)、初始事件(近端或远端深静脉血栓形成或肺栓塞)以及相关情况(癌症、手术等)提供了关于抗凝治疗中断后复发风险的重要信息。其次,在抗凝治疗中断时,D-二聚体水平和残余血栓已被表明是复发性VTE的预测指标。目前的证据表明,停止治疗后复发的风险很大程度上取决于VTE急性发作是否得到有效治疗以及患者发生新的VTE发作的内在风险。所有急性VTE患者均应接受口服抗凝治疗三个月。在该治疗期结束时,医生应决定停药或进行长期抗凝治疗,并定期重新评估延长抗凝治疗的益处。基于患者复发性VTE和出血并发症的内在风险以及患者的偏好,部分患者可被分配至接受维生素K拮抗剂(VKA)长期治疗,并定期重新评估延长抗凝治疗的益处。目前正在评估常规抗凝治疗后用于VTE二级预防的替代策略。癌症患者在VTE的长期治疗中应使用低分子肝素而非华法林。这些患者应考虑至少在基础疾病缓解前进行延长抗凝治疗。复发性静脉血栓栓塞的风险可通过两步算法进行估计。首先,患者的特征(性别)、初始事件(近端或远端深静脉血栓形成或肺栓塞)以及相关情况(癌症、手术等)对于估计抗凝治疗中断后的复发风险至关重要。其次,抗凝治疗中断时D-二聚体水平和残余血栓与复发风险之间已显示出相关性。目前可用的抗凝剂在降低复发性静脉血栓栓塞的发生率方面是有效的,但它们与出血并发症风险增加相关。所有急性静脉血栓栓塞患者均应接受口服抗凝治疗三个月。在该治疗期结束时,医生应决定最终停药或进行长期抗凝治疗,并定期重新评估延长抗凝治疗的益处。