Department of Surgery, Division of Vascular Surgery, Staten Island University Hospital, Staten Island, NY, USA.
J Vasc Surg. 2012 Jan;55(1):136-40. doi: 10.1016/j.jvs.2011.07.088. Epub 2011 Oct 7.
The clinical significance of isolated calf vein thrombosis (ICVT) remains controversial. Several studies have shown that the majority of ICVT do not propagate above the knee while other studies have suggested ICVT propagation and recommend full anticoagulation. The purpose of this study was to determine the progression of ICVT, identify risk factors for clot propagation, and to evaluate further thrombotic events associated with it.
This study consisted of 156 patients and a total of 180 limbs. All patients included had ICVT involving either the tibial, peroneal, gastrocnemius, or the soleal vein. After initial diagnosis, all patients were started on prophylactic dose of low molecular weight heparin (LMWH) or unfractionated heparin, unless already anticoagulated. All limbs were monitored using duplex ultrasonography scans at intervals of 2 to 3 days, 1 to 3 months, and 6 to 8 months from the initial time of diagnosis. Outcomes examined included lysis of clot, propagation to a proximal vein, and pulmonary emboli.
ICVT was detected in 180 limbs of 156 patients. No significant difference was noted in the gender of the patients or limb preference. Twenty-four patents had both limbs involved. The mean age was 77 years old and the mean follow-up was 5.1 months. The soleal vein was most commonly involved. The second most common vein involved was peroneal, followed by posterior tibial and then gastrocnemius. The least commonly involved vein was the anterior tibial with only one positive result on each side. Fifteen of 180 limbs (9%) had complete resolution of the thrombus within 72 hours. Of these, six were anticoagulated to a therapeutic level. All patients had a follow-up duplex scan within 1 to 3 months' time, and none had recurrence. At the 1 to 3-month follow-up, 11 of 180 patients (7%) had propagation to a proximal vein; all of whom were in a high-risk group to develop a deep vein thrombosis (DVT), either after an orthopedic procedure, stroke, or malignancy. Nine of 156 patients developed a pulmonary emboli also diagnosed within the 1 to 3-months' time period. At the 6 to 8-month follow-up, there was no further propagation of any additional limbs and no further incidences of pulmonary emboli.
ICVT can be safely observed in asymptomatic patients without therapeutic anticoagulation. In our study, patients who have had orthopedic procedures, those with malignancy, and those that were immobile seemed to have a higher incidence of clot propagation. In this group, we recommend full anticoagulation until the patient is ambulatory or the follow-up duplex scan is negative. Our data also suggest that a follow-up duplex scan is not beneficial when performed within 72 hours or after 3 months.
孤立性小腿静脉血栓（ICVT）的临床意义仍存在争议。一些研究表明，大多数 ICVT 不会在膝盖以上部位蔓延，而其他研究则表明 ICVT 会蔓延，并建议进行充分抗凝治疗。本研究旨在确定 ICVT 的进展情况，确定血栓蔓延的危险因素，并评估与之相关的进一步血栓事件。
本研究共纳入 156 例患者，共计 180 条肢体。所有纳入的患者均存在累及胫后、腓肠、比目鱼肌或跖骨静脉的 ICVT。初始诊断后，所有患者均开始接受低分子肝素（LMWH）或未分级肝素的预防性剂量治疗，除非已进行抗凝治疗。所有肢体均在初始诊断后 2 至 3 天、1 至 3 个月和 6 至 8 个月内通过双功能超声进行监测。检查的结果包括血栓溶解、向近端静脉蔓延和肺栓塞。
在 156 例患者的 180 条肢体中发现了 ICVT。患者的性别或肢体偏好无显著差异。24 例患者有双侧肢体受累。平均年龄为 77 岁，平均随访时间为 5.1 个月。最常受累的静脉是比目鱼肌静脉，其次是腓肠肌后静脉，然后是胫后静脉，最不常受累的静脉是胫前静脉，每侧只有一个阳性结果。180 条肢体中有 15 条（9%）在 72 小时内完全溶解血栓。其中 6 条接受了治疗性抗凝治疗。所有患者均在 1 至 3 个月内进行了随访双功能超声检查，均未复发。在 1 至 3 个月的随访中，180 例患者中有 11 例（7%）发生近端静脉蔓延；所有患者均存在发生深静脉血栓（DVT）的高风险，要么是在骨科手术后，要么是在中风或恶性肿瘤后。9 例患者在 1 至 3 个月的时间内也被诊断为肺栓塞。在 6 至 8 个月的随访中，没有其他肢体进一步蔓延，也没有进一步发生肺栓塞。
无症状患者可安全观察 ICVT，无需进行治疗性抗凝治疗。在我们的研究中，接受过骨科手术、患有恶性肿瘤和长期卧床的患者似乎更易发生血栓蔓延。对于这些患者，我们建议在患者能够活动或随访双功能超声检查结果为阴性之前进行充分抗凝治疗。我们的数据还表明，在 72 小时内或 3 个月后进行随访双功能超声检查并无益处。
