Marco P. Donadini, Department of Clinical and Experimental Medicine, University of Insubria, Via Guicciardini, 9, 21100 Varese, Italy, Tel.: + 39 0332 278831, Fax: +39 0332 278818, E- mail:
Thromb Haemost. 2014 Jan;111(1):172-9. doi: 10.1160/TH13-04-0336. Epub 2013 Oct 24.
Residual venous obstruction (RVO) could improve the stratification of the risk of recurrence after unprovoked deep vein thrombosis (DVT), but results from clinical studies and study-level meta-analyses are conflicting. It was the objective of this analysis to determine if RVO is a valid predictor of recurrent venous thromboembolism (VTE) in patients with a first unprovoked DVT who had received at least three months of anticoagulant therapy. Individual patient data were obtained from the datasets of original studies, after a systematic search of electronic databases (Medline, Embase, Cochrane Library), supplemented by manual reviewing of the reference lists and contacting content experts. A multivariate, shared-frailty Cox model was used to calculate hazard ratios (HRs) for recurrent VTE, including, as covariates: RVO; age; sex; anticoagulation duration before RVO assessment; and anticoagulation continuation after RVO assessment. A total of 2,527 patients from 10 prospective studies were included. RVO was found in 1,380 patients (55.1%) after a median of six months from a first unprovoked DVT. Recurrent VTE occurred in 399 patients (15.8%) during a median follow-up of 23.3 months. After multivariate Cox analysis, RVO was independently associated with recurrent VTE (HR = 1.32, 95% confidence interval [CI]: 1.06-1.65). The association was stronger if RVO was detected early, i.e. at three months after DVT (HR = 2.17; 95% CI: 1.11-4.25), but non-significant if detected later, i.e. >6 months (HR = 1.19; 95% CI: 0.87-1.61). In conclusion, after a first unprovoked DVT, RVO is a weak overall predictor of recurrent VTE. The association is stronger if RVO is detected at an earlier time (3 months) after thrombosis.
残留静脉阻塞（RVO）可以改善无诱因深静脉血栓形成（DVT）后复发风险的分层，但来自临床研究和研究水平荟萃分析的结果存在冲突。本分析的目的是确定在接受至少三个月抗凝治疗的首次无诱因 DVT 患者中，RVO 是否是复发性静脉血栓栓塞（VTE）的有效预测因子。从原始研究的数据集获取了个体患者数据，对电子数据库（Medline、Embase、Cochrane Library）进行了系统检索，并通过手动查阅参考文献和联系内容专家进行了补充。使用多变量共享脆弱性 Cox 模型计算复发性 VTE 的风险比（HR），包括作为协变量的：RVO；年龄；性别；RVO 评估前的抗凝时间；以及 RVO 评估后的抗凝时间。纳入了来自 10 项前瞻性研究的 2527 例患者。在首次无诱因 DVT 后中位时间为 6 个月时，1380 例患者（55.1%）发现 RVO。在中位随访 23.3 个月期间，399 例患者（15.8%）发生复发性 VTE。多变量 Cox 分析后，RVO 与复发性 VTE 独立相关（HR=1.32，95%置信区间[CI]：1.06-1.65）。如果 RVO 早期（DVT 后 3 个月）检测到，相关性更强（HR=2.17；95%CI：1.11-4.25），但如果晚期（>6 个月）检测到，相关性不显著（HR=1.19；95%CI：0.87-1.61）。总之，在首次无诱因 DVT 后，RVO 是复发性 VTE 的一个较弱的总体预测因子。如果在血栓形成后更早（3 个月）检测到 RVO，相关性更强。
