Patterns of venous insufficiency after an acute deep vein thrombosis

BACKGROUND: The purpose of this study was to investigate patterns of venous insufficiency during a 12-month period after an acute deep vein thrombosis. STUDY DESIGN: Seventy limbs in 67 patients with an acute deep vein thrombosis (DVT) involving 147 anatomic segments were evaluated with duplex scanning at 1 month, 3 months, 6 months, and 1 year. Venous segments were examined whether they were occluded, partially recanalized, or totally recanalized, and the development of venous reflux was evaluated. RESULTS: The segments investigated were the common femoral vein (38 segments), femoral vein (33 segments), popliteal vein (36 segments), and calf veins (40 segments). There were 35 limbs with isolated DVT and the remaining 35 had multisegment DVT. At 1 year, thrombi had fully resolved in 76% of the segments, 20% remained partially recanalized, and 5% were occluded. The venous occlusion was most predominant in the femoral vein (21%) at 1 year. On the contrary, rapid recanalization was obtained in calf veins than in proximal veins at each examination (p < 0.01). Deep vein insufficiency was detected as early as 1 month after development of DVT, and the reflux was most predominant in popliteal veins (56%), followed by femoral veins (18%). No reflux was found in calf veins. Multisegment DVTs had a significantly higher incidence of deep vein insufficiency than single segment DVTs at 1 year. Development of superficial venous insufficiency was found in 5 limbs (7%) and perforating vein insufficiency in 5 (7%). CONCLUSIONS: Lower extremity venous segments showed different proportions of occlusion, partial recanalization, and total recanalization. Calf veins showed more rapid recanalization than proximal veins. Venous reflux was noted as early as 1 month. The limbs involving multisegment DVTs on initial examination had a higher incidence of deep vein insufficiency and could require much longer followup studies.     

Significance of the soleal vein for the pathogenesis of deep vein thrombosis leading to acute massive pulmonary thromboembolism

Prophylaxis of deep vein thrombosis (DVT) is a serious matter as the source of pulmonary thromboembolism (PTE) in hospitalized patients. Leg DVT is classified into three groups: iliac, femoral and calf types. Among them, calf type DVT is closely connected with PTE. Especially, soleal vein is the most frequent site of thrombi formation occurring with venous stagnation. Although most cases of soleal vein thrombosis are resolved soon without specific treatments: in around 20% of cases the thrombosis propagates to the proximal drainage vein as float thrombi e.g. from peroneal vein and posterior tibial vein to popliteal vein. Thereafter, the organization of thrombi leads to venous valve insufficiency, so-called postthrombotic syndrome. As a result, it worsens blood stagnation and induces recurrent thrombi formation. The broad prophylaxis of DVT in the soleal veins for inpatients is the most important point in the initial stage of hospitalization.     

下肢深静脉血栓形成外科治疗的并发症分析

目的 总结下肢深静脉血栓形成(deep vein thrombosis,DVT)外科治疗中并发症的治疗经验.方法 回顾性分析2001年1月至2008年1月外科治疗下肢深静脉血栓形成171例的临床资料.先行下腔静脉滤器置入,对近段髂股静脉血栓采用Fogarty取栓管取栓73例;Amplatz消融器(ATD)消融血栓55例;Acolysis超声消融器消融血栓43例,远段血栓以挤压法驱出,术中造影,对合并存在髂静脉病变则先行介人治疗,并建立临时性股动静脉瘘.结果 本组171例,157例治疗成功,14例失败.其中Fogarty取栓成功70例,失败3例;ATD成功52例,失败3例;超声消融成功35例,失败8例.置人永久性滤器51例,可回收滤器32例,临时性滤器88例.143例存在髂静脉狭窄或闭塞,左侧139例,右侧4例.球囊扩张后置人支架41例.术中造影见血栓残留80例,血管穿孔破裂14例,滤器下方血栓18例.全组无死亡和肺动脉栓塞发生.术后随访142例,随访时间2～84个月,平均38个月.21例髂静脉再狭窄,血栓再发36例,支架移位6例,支架断裂2例.结论 外科治疗下肢深静脉血栓形成是一种有效方法,但同时应注意对其并发症的防治.     

The natural history of calf vein thrombosis: Lysis of thrombi and development of reflux

Purpose: Although the fact is well accepted that deep venous thrombosis (DVT) of the iliac, femoral, and popliteal veins can lead to the post-thrombotic (postphlebitic) syndrome, the significance of isolated calf DVT on the development of late venous sequelae and physiologic calf dysfunction is unknown. The purpose of this study was to review the outcome of 58 limbs with isolated calf DVT and report the clinical, physiologic, and imaging results up to 6 years after the onset of DVT. Methods: The study consisted of 58 limbs of 54 patients in whom isolated calf vein DVT was diagnosed between 1990 and 1995. Proximal propagation of clot, lysis of thrombi, and development of symptomatic pulmonary emboli were examined. Of the patients, 28 received anticoagulation therapy, and 26 did not, but they had follow-up with serial duplex scans. At late follow-up 1 to 6 years later (median, 3 years), 23 patients were examined for the post-thrombotic syndrome, and all 23 underwent clinical examination, color-flow duplex scanning, and air plethysmography. Results: Proximal propagation of DVT from the calf veins into the popliteal or thigh veins occurred in 2 of 49 cases (4%) within 2 weeks of diagnosis. No patient had clinically overt pulmonary emboli develop regardless of whether anticoagulation therapy was received or not. The most common site for calf DVT was the peroneal vein (71%). Complete lysis of calf thrombi was found in 88% of the cases by 3 months. At 3 years, 95% of the patients were either asymptomatic or mildly symptomatic, and 5% had discoloration of the limb. No ulcers occurred. By air plethysmography, physiologic abnormalities were found in 27% of the cases, which was not significantly different from normal controls. Valvular reflux by duplex scanning of the calf vein segment with DVT was found in 2 of 23 cases (9%). However, reflux in at least one venous segment not involved with DVT was found in 7 of 23 cases (30%), which was higher than, but not statistically different from, normal controls, with reflux occurring in 5 of 26 cases (19%). Conclusions: Isolated calf vein DVT leads to few early complications (ie, clot propagation, pulmonary emboli) and few adverse sequelae at 3 years. The peroneal vein is most commonly involved and should be a part of the routine screening for DVT. Lysis of clot usually occurs by 3 months. Although valvular reflux rarely is found in the affected calf vein at 3 years, reflux may be found in adjacent uninvolved veins in approximately 30% of the cases. The question of whether this will lead to future sequelae, such as ulceration, will require longer follow-up. (J Vasc Surg 1998;28:67-74.)     

Extended lower limb venous ultrasound for the diagnosis of proximal and distal vein thrombosis in asymptomatic patients after total hip replacement.

OBJECTIVE: To assess the performance of extended lower limb venous ultrasound (US) for the diagnosis of asymptomatic deep vein thrombosis (DVT) and to estimate a 3-month DVT incidence on repeated US after total hip replacement. DESIGN: Diagnostic performance study and prospective cohort study. MATERIALS AND METHODS: US was compared to phlebography in 70 consecutive patients and interobserver agreement was assessed in the last 48 patients at day 8. US was repeated in these 48 patients at day 13 and day 90. RESULTS: Phlebography demonstrated a DVT in 18/70 (26%) patients, with five proximal and 13 distal and US in 23/70 (33%) patients, with eight proximal and 15 distal. Sensitivity and specificity of US with 95% CI were 94% (73-100) and 89% (76-96), respectively. Sensitivity in isolated distal vein thrombosis was 92% (67-99). The Kappa coefficient for agreement between observers was 0.84 (0.66-1.00). Follow-up showed a DVT in 15/48 (31%) patients on day 8, in 20/48 patients (42%) on day 13. DVT recurred in two patients during follow-up. CONCLUSIONS: The incidence of asymptomatic DVT is still significant despite prophylaxis but most DVTs remain distal and occur in the first 2 weeks. Extended US could replace phlebography for systematic screening in clinical trials using surrogate endpoints in view of its high accuracy and reliability.     

Prospective screening for postoperative deep venous thrombosis in patients undergoing infrainguinal revascularization

PURPOSE: The incidence of deep venous thrombosis (DVT) in patients undergoing infrainguinal bypass graft procedures has not been well documented, and the need for routine prophylaxis remains controversial. The purpose of this study was to prospectively evaluate the risk of postoperative DVT complicating infrainguinal revascularization. METHODS: Seventy-four patients undergoing infrainguinal bypass graft procedures during a 12-month period were prospectively screened for DVT. Bilateral lower extremity venous duplex scan imaging was performed preoperatively and within 1 week and 6 weeks, postoperatively. Routine DVT prophylaxis was not used, with anticoagulation reserved for specific indications. RESULTS: Of the 74 patients screened, three patients (4.1%) had DVT identified on preoperative venous duplex scan imaging and were excluded from the study. Of the remaining 71 patients enrolled, only two patients (2.8%) had postoperative DVT. Postoperative DVT was ipsilateral to the bypass graft extremity in both patients, with involvement of the peroneal vein in one patient and the femoral vein in the other. Although routine prophylaxis was not used, 18 of these patients (25%) were anticoagulated for other indications, with DVT occurring in one patient (5.6%). Of the remaining 53 patients who did not receive postoperative anticoagulation, only one patient (1.8%) had DVT. CONCLUSIONS: According to this prospective study, the risk of postoperative DVT in patients undergoing infrainguinal revascularization is low. Routine prophylaxis is not recommended, with postoperative anticoagulation reserved for specific indications.     

Prevalence of Preoperative Lower Extremity Deep Vein Thrombosis in Bilateral Calcaneal Fractures

There are no studies on epidemiologic characteristics of deep vein thrombosis (DVT), when specified at in patients with bilateral calcaneal fractures. This study aimed to address the preoperative DVT in bilateral calcaneal fractures. Between October 2014 and December 2018, adult patients presenting with bilateral calcaneal fractures and having preoperative Duplex ultrasound (DUS) of bilateral lower extremities for detection of DVT were included. Their medical data were collected, with regards to demographics, comorbidities, injury-related data and biomarkers. Baseline characteristics between patients with and without DVT were compared using bivariate tests. The further multivariate logistics regression analysis was conducted to identify independent factors associated with DVT. In total, 258 patients with bilateral calcaneal fractures were included, with 21 (8.1%) having preoperative DVT, diagnosed at 7.7 ± 4.2 days after injury. The prevalence rate of proximal DVT was 1.9% and of distal DVT was 6.2%. Thirty five thrombi were found, with 6 (17.1%) in proximal veins and 29 (82.9%) in distal veins. Nine patients had DVTs in multiple veins, and 2 patients had bilateral DVTs. The multivariate analyses showed history of allergy (odds ratio [OR] = 2.17), concurrent other fractures (OR = 4.53), prolonged time since injury (for each day, OR = 1.16), elevated plasma D-dimer level (≥1.73 vs <1.73 mg/L, OR = 3.74) and reduced albumin level (<34.2 g/L vs ≥34.2 g/L, OR = 2.92) were independent factors associated with DVT. Multiple factors were identified to be associated with DVT and greater consideration should be given to the use of pharmacologic prophylaxis in patients involving these factors, to reduce DVT occurrence.     

Thrombosis in unusual sites of the lower extremity veins

BACKGROUND: Thrombosis in unusual locations in the lower extremity veins has not been assessed. These veins are not imaged routinely and therefore information about them is lacking. METHODS: This study was designed to evaluate the natural history of deep vein thrombosis (DVT) in unusual sites. Patients with DVT in all thigh veins but the femoral vein were included. Patients with thrombi in any other vein in the first examination and those with history of DVT were excluded. Duplex ultrasound (DU) examination was performed to exclude thrombosis in the lower extremity in patients with signs and symptoms of venous thromboembolism and also in high-risk, asymptomatic patients. All veins from the distal external iliac vein to the lower calf were imaged. The deep femoral, femoropopliteal, lateral thigh, sciatic, and muscular thigh veins were examined. These patients were followed at 1 week, 1 month, 6 months, 1 year, and yearly thereafter, for thrombus propagation, resolution, and reflux. RESULTS: Among the 15,850 DU performed in the vascular laboratory at Loyola University Medical Center, in a 10-year period to rule out DVT, 2568 (16.2%) were positive and 14 cases (7 males, 0.54% among the patients with DVT and 0.088% among the entire population) involved thromboses in unusual locations. Ten cases involved the left lower extremity and four the right. The unusual DVT cases were associated with medical and surgical conditions or were idiopathic in 11 patients, whereas three had Klippel-Trenaunay syndrome (KTS). The veins involved in the first group of patients were the deep femoral (8), the femoropopliteal (2), and the deep external pudendal (1). The patients with KTS had involvement of muscular thigh veins (1), and the lateral thigh vein and the sciatic vein (2). Thrombi propagation with extension to the common femoral vein was seen in four of the 14 patients: two from the deep femoral vein, one from the femoropopliteal vein, and one from the deep external pudendal vein. There were two incidences of pulmonary embolism (PE) one of which was fatal. At final follow-up, two patients developed recurrent DVT and nine had signs and symptoms of chronic venous disease. CONCLUSIONS: The involvement of the studied veins in DVT is extremely rare. Thrombosis in these veins can follow the natural course of thrombosis in the more usual locations and is associated with lethal incidences of PE. Therefore, the association of these veins with all the grave sequelae of thromboembolic disease suggests that inclusion of these veins in routine lower extremity duplex scans would be beneficial.     

Extent of thrombus evaluated in patients with recurrent and first deep vein thrombosis

OBJECTIVES: The objective of this retrospective study was to document the extent of thrombus in patients with recurrent and first deep vein thrombosis (DVT). Patients and Methods: A total of 864 patients with DVT of the leg were enrolled in the study. They were divided into two groups: patients with recurrent DVT (n = 233) of the leg, and patients with first DVT of the leg (n = 631). In both groups the extent of the thrombus was evaluated by duplex scanning, contrast venography, or magnetic resonance imaging. Thrombus involving veins distal to the popliteal vein was classified as distal DVT, whereas involvement of the popliteal vein and proximal was classified as proximal DVT. RESULTS: We could demonstrate that involvement of proximal segments (CEAP anatomic classification 1-9) occurred significantly more often in patients with recurrent DVT than in patients with the first DVT (P <.001). The incidence of pulmonary embolism (PE) and the clinical symptoms of PE were equally distributed between patients with recurrent DVT and those with first DVT (P >.05). Only one patient died as a consequence of PE in our patient sample. CONCLUSIONS: In our experience, patients with recurrent DVT have a higher frequency of proximal DVT. Nevertheless, the incidence of PE is similar in patients with recurrent and those with first DVT.     

Progress in the diagnosis of deep venous thrombosis: the efficacy of real-time B-mode ultrasonic imaging

Seventy-six limbs with clinically suspected acute deep venous thrombosis (DVT) were evaluated by means of ultrasonic imaging (UI) to define the ability of this technique to detect acute and chronic venous obstruction and to determine the origin and distribution of venous thrombi. UI was compared with ascending contrast phlebography in 46 limbs and was found to be 100% accurate in detecting both acute and chronic venous thrombosis. Overall, acute DVT was present in 63 of 76 limbs (83%) studied. Acute DVT was found in 24% and recurrent acute DVT in 76%. Our results indicate that although the calf veins are the most common site of involvement (89%), thrombi may frequently arise simultaneously in multiple anatomic sites. All limbs with recurrent acute DVT had evidence of previous calf thrombi but only 13% had previous proximal disease. This suggests that asymptomatic calf DVT is common and the prevalence of recurrent acute DVT is significantly greater than previously believed. We found UI is a practical, accurate, non-invasive method for investigating the pathogenesis of venous disease.     

Five-year outcome study of deep vein thrombosis in the lower limbs

OBJECTIVE: Venous disease was evaluated in relation to post-thrombotic syndrome 5 years after deep venous thrombosis (DVT) in patients treated with a regimen of low-molecular-weight heparin (LMWH) and warfarin in a Hospital-in-the-Home program. METHODS: The presence of flow, reflux and compressibility in 51 patients (102 limbs, 54 with DVT and 48 without DVT) was assessed by duplex ultrasound scanning. Blood tests were carried out for prothrombotic screening. Venous disease was related to pathologic severity of post-thrombotic syndrome, characterized by the CEAP (clinical, etiologic, anatomic, pathophysiologic) classification on a scale of 0 to 6. RESULTS: In the 102 limbs studied, 30 patients (59%) had an underlying thrombophilic disorder. The most common cause of DVT was postoperation and prolonged immobilization not related to postoperation. The most common thrombophilic abnormalities were anticardiolipin antibody and a deficiency of protein C or S, or both. Twenty-six limbs (48%) had proximal involvement (proximal and proximal plus distal DVT); resolution (recanalization or normal vein) in these limbs was seen in 85% at 6 months and 96% at 5 years. After 5 years, 25 of these proximal DVT limbs (96%) developed reflux and there were 4 limbs in CEAP class 0, 8 in classes 1 to 3, and 14 in classes 4 to 6. All of the 28 limbs (52%) with distal DVT showed DVT resolution by 6 months. After 5 years, 10 limbs (36%) developed reflux, and 13 limbs were in class 0, 12 in classes 1 to 3, and 3 limbs in classes 4 to 6. No DVT was detected in the 48 contralateral limbs, but reflux was detected in 25 limbs (52%), predominately in the superficial veins (16 limbs, 64%). CONCLUSIONS: The resolution of thrombus was more rapid and complete in patients with distal DVT than in those with proximal DVT. Patients with proximal DVT developed a more severe form of post-thrombotic syndrome that was likely related to the development of deep venous reflux. An important finding of this study was an unexpectedly high incidence of venous reflux in the apparently unaffected limb. Although these non-DVT limbs were not investigated at presentation, our data is consistent with the hypothesis that DVT may result in a more systemic disorder of venous function.     

The value of rapid D-dimer testing combined with structured clinical evaluation for the diagnosis of deep vein thrombosis.

PURPOSE: Large studies have shown that most cases referred for duplex sonography for suspected deep vein thrombosis (DVT) have normal scan results. For medical and economic reasons, a preselection procedure, which allows the detection of true-negative cases before duplex scanning, is required; this procedure should be characterized by a high sensitivity and a high negative predictive value. METHODS: In 343 patients (398 lower extremities) with suspected DVT, the DVT probability was clinically assessed, and a whole blood D-dimer agglutination test and a duplex scan were performed. The diagnostic sensitivities of the D-dimer test alone, a high clinical DVT probability alone, and the combination of both were evaluated. RESULTS: The sensitivity values for the D-dimer test to diagnose proximal and distal DVTs were 88.7% and 80.9%, the negative predictive values (NPV) were 96.3% and 97.9%, and the specificity and the positive predictive value (PPV) were 54.8% and 49.6% and 26.6% and 8.2%, respectively. The sensitivities of the clinical DVT probability assessment for the diagnosis of proximal and distal DVTs were 83.9% and 66.7%, respectively; the corresponding NPVs were 94.9% and 96.5%, respectively. The specificity was 56.1% and 50.8%, and the PPVs were 26.1% and 7.0%, respectively. The combined use of the results of the clinical probability assessment and the D-dimer test resulted in sensitivities for proximal and distal DVTs of 98.4% and 90.5%, NPVs of 99.3% and 98.6%, a specificity of 43.4% and 38.4%, and PPVs of 24. 3% and 7.6%, respectively. CONCLUSION: The combined use of a clinical DVT probability assessment scheme and the D-dimer test largely avoids false negative results, has a high sensitivity and NPV, helps to reduce the costs of DVT diagnosis, and may, in the future, be useful as a preselection procedure before duplex sonography.     

The patterns and distribution of residual abnormalities between the individual proximal venous segments after an acute deep vein thrombosis

INTRODUCTION: The subsequent course of residual abnormalities after an acute deep vein thrombosis (DVT) can vary within individual venous segments. To investigate the pattern of response within the individual venous segment, we used sequential duplex scanning to determine whether certain segments are more likely to recanalize or remain occluded. METHODS: The anatomic segments involved in 63 above-knee DVTs were examined with duplex scanning at 1 week, 1 month, 6 months, and 1 year after the acute event. The segments under investigation were the external iliac vein (EIV), common femoral vein (CFV), superficial femoral vein (SFV), and popliteal vein (PV). Reflux studies were performed at each follow-up examination. During the follow-up period the segments were examined to see whether they were occluded, partially recanalized, or totally recanalized and the development of reflux was noted. RESULTS: Most DVTs were multisegmental with a total number of 171 sites involved. Initially, a greater number of segments were occluded (71%) than partially thrombosed (29%). The occluded segments were predominantly in the SFV and PV. At 1 year the thrombi had fully resolved in 60% of the venous segments, 27% remained partially recanalized, and 13% were occluded. The venous segments that resolved within the first 6 months had a higher rate of valvular competence than those that resolved from 6 months to 1 year. The SFV and PV had a higher incidence of valvular incompetence than the EIV and CFV. All venous segments that were partially recanalized at 1 year were found to have significant reflux. The SFV had the highest incidence of total occlusion at the end of 1 year (36%). Many of the occluded SFVs had established collateral pathways that displayed no evidence of reflux. CONCLUSION: The lower extremity venous segments differ in respect to their tendencies to partially or fully recanalize or remain occluded. All partially recanalized segments displayed reflux. Fully resolved segments that recanalized within the first 6 months were more likely to have competent valves than those that recanalized after 6 months. In the presence of an occluded SFV, collateral pathways establish rapidly. No reflux was found in these collaterals.     

Re-evaluation of iliac compression syndrome using magnetic resonance imaging in patients with acute deep venous thromboses

BACKGROUND: The majority of proximal deep venous thromboses (DVTs) are thought to have propagated as a contiguous column from the calf veins. However, several authors have proposed that ileofemoral DVT commonly originates in the left common iliac vein (LCIV) at a site of compression by the overlying right common iliac artery (RCIA/LCIV compression). This mechanism could explain both the left-sided predominance of ileofemoral DVT and the finding that ileofemoral DVT frequently occurs either in the absence of calf vein thrombosis (isolated ileofemoral DVT) or is not contiguous with calf vein thrombosis (noncontiguous ileofemoral DVT). This mechanism remains unconfirmed. OBJECTIVES: The purpose of this study was to detect RCIA/LCIV compression using multimodal magnetic resonance imaging in thrombosed and patent iliac veins, to determine whether RCIA/LCIV compression occurs more frequently in cases of left ileofemoral DVT than other types of DVT, and to determine if RCIA/LCIV compression is specifically associated with left isolated and noncontiguous ileofemoral DVT. PATIENTS AND METHODS: This prospective study conducted at the 1355-bed University Hospital included 18 patients with ileofemoral DVT, 23 with femoropopliteal DVT, 15 with isolated calf DVT recruited consecutively, and 28 control patients in whom DVT had been excluded. Interventions included magnetic resonance direct thrombus imaging (MRDTI), venous enhanced peak arterial magnetic resonance venography (VESPA) and magnetic resonance arteriography (MRA) within 48 hours of routine conventional venography (CV). RCIA/LCIV compression of patent LCIVs was assessed using VESPA and MRA; RCIA/LCIV compression of thrombosed LCIVs was assessed using MRDTI and MRA. The extent of calf and popliteal thrombosis was detected using CV; the extent of femoral and iliac thrombosis was detected using VESPA and MRDTI. RESULTS: RCIA/LCIV compression was more commonly detected in cases of left ileofemoral DVT (9/16 cases) than in cases of left femoropopliteal DVT (1/11 cases; P = .018), right femoropopliteal DVT (2/12 cases; P = .054), left isolated calf DVT (1/9 cases; P = .037), right isolated calf DVT (0/6 cases; P = .046) and control patients (4/28 cases; P = .006). RCIA/LCIV compression was more commonly detected in cases of left isolated ileofemoral DVT (6/6 cases; P = .005), and cases of left noncontiguous ileofemoral DVT (2/2 cases; P = .067) than in cases in which thrombosis was contiguous from the calf to the iliac veins (1/8 cases). CONCLUSION: RCIA/LCIV compression was strongly associated with left ileofemoral DVT and was specifically associated with cases that involve independent ileofemoral thrombosis.     

Stenting of common iliac vein obstructions combined with regional thrombolysis and thrombectomy in acute deep vein thrombosis.

OBJECTIVES: To evaluate the efficacy of stent placement after infrainguinal loco-regional thrombolysis and iliac thrombectomy (surgical TT) of acute deep vein thrombosis (DVT) in patients with May-Thurner-Syndrome. MATERIAL AND METHODS: We retrospectively analysed a group of 11 patients (9 women) (mean age 34 years, range 16-64 years) with surgical TT and additional intra-operative stenting due to compression of the common iliac vein. Patients underwent venography to demonstrate outflow patency after surgical TT, and to identify any obstruction at the level of the left-sided common iliac vein ("Beckenvenen-Sporn"). Obstruction at the level of arterial crossing was treated using Wallstents placed via an introducer sheath from the inguinal access site. Stents were fully deployed using balloons adjusted to the size of vein. Patients were treated with oral anticoagulants for 6 months, and followed using duplex ultrasonography. RESULTS: Technical success defined as complete vein patency and normal valve function was documented in all 11 patients. One patient needed early stent extension due to residual stenosis. At 6 months follow-up one patient (9%) had an asymptomatic occlusion of the stented common iliac vein. In all 11/11 (100%) patients the femoral segment was found to be patent, and in 1/11 (9%) there was mild reflux with few clinical symptoms of post-thrombotic syndrome. The calculated cumulative primary patency rate for venous iliac stents was 82%, and assisted patency rate was 91%, which remained unchanged over a mean follow-up of 22 months. CONCLUSION: Combining surgical TT and stenting of common iliac vein obstructions in DVT is safe, effective, and results in a acceptable venous patency.     

腔内治疗髂静脉梗阻合并急性深静脉血栓的临床经验

目的探讨腔内治疗髂静脉梗阻合并急性深静脉血栓(deep vein thrombosis,DVT)的临床效果。方法 2008年10月～2011年9月,19例急性DVT接受手术取栓联合同侧髂静脉腔内支架置入术。DVT位于左髂-股静脉及下腔静脉3例,双侧髂-股静脉2例,其余14例均在左髂静脉。均有患肢明显肿胀,其中12例伴患肢疼痛。DVT发病时间(3.2±1.3)d。取栓前均先置入下腔静脉滤器,取栓后即刻静脉造影发现髂静脉狭窄者先行球囊扩张再置入自膨式支架。结果 18例取栓后造影示髂静脉狭窄,其中髂静脉压迫综合征(iliac vein compression syndrome,IVCS)15例(78.9%),残留狭窄3例;1例未发现髂静脉狭窄。18例有狭窄者共置入22枚自膨式支架,手术均获成功。1例术后伤口血肿。随访16例,随访时间2～26个月(平均10.3月),疼痛症状均消失,2例行走后下肢轻度肿胀,均未出现血栓复发。结论腔内治疗髂静脉梗阻合并急性DVT安全、有效,早期临床结果满意。     

Effect of mechanical compression on the prevalence of proximal deep venous thrombosis as assessed by magnetic resonance venography

BACKGROUND: Patients have been shown to be at greater risk for deep venous thrombosis, particularly proximal thrombosis, after total hip arthroplasty. Proximal thrombi are more likely to develop into pulmonary emboli than are distal thrombi. The purpose of this randomized, prospective study was to compare the prevalence of pelvic and proximal lower-extremity deep venous thrombosis after primary total hip arthroplasty between patients treated with an impulse mechanical compression device for prophylaxis and those treated with prophylactic stockings. METHODS: One hundred patients were evaluated, with use of magnetic resonance venography, for proximal deep venous thrombosis after total hip arthroplasty. Fifty patients were treated with a mechanical compression device on both lower extremities, and the other fifty patients received only prophylactic stockings. Both groups of patients received hypotensive epidural anesthesia and 325 mg of aspirin twice a day. RESULTS: Overall, proximal deep venous thrombi were found in 15% of the 100 patients. Of the fifty patients treated with mechanical compression, 8% (four) had a positive venogram. Of the fifty control patients, 22% (eleven) had a positive venogram (p < 0.05). However, overall the rate of occlusive thrombi was 6% (six) compared with an overall rate of nonocclusive thrombi of 9% (nine). The rate of occlusive thrombi was 2% (one of fifty) in the study group and 10% (five of fifty) in the control group (p = 0.04). CONCLUSIONS: On the basis of this study, we concluded that patients managed with total hip arthroplasty benefit from a reduction in the rates of femoral and pelvic deep vein thrombosis when they are treated with hypotensive epidural anesthesia, mechanical compression, and aspirin and are subsequently assessed with magnetic resonance venography.     

Asymptomatic Deep Venous Thrombosis After Elective Hip Surgery Could Be Allowed to Remain in Place Without Thromboprophylaxis After a Minimum 2-Year Follow-Up

BackgroundIt is not clear how to treat asymptomatic deep venous thromboses (DVTs) following elective hip arthroplasty because the natural course of DVTs is unclear. It is therefore valuable to understand the natural course of DVTs and their relation to thromboprophylactic methods.MethodsWe followed 742 consecutive patients who underwent elective hip arthroplasty followed by mechanical or chemical prophylaxis of a DVT. All patients underwent preoperative and postoperative duplex ultrasonography of both limbs. Patients who developed postoperative DVT in the popliteal or calf vein were followed without thromboprophylaxis. DVT-positive patients were prospectively followed up with duplex ultrasonography at 3, 6, 12, and 24 months postoperatively.ResultsIncidences of preoperative and postoperative DVTs were 3.9% and 33.0%, respectively. Nonfatal pulmonary embolism (PE) occurred in 1 patient after negative echography. All DVTs that developed in the calf vein postoperatively and without anticoagulation remained benign, and 93% of the DVTs ultimately disappeared.ConclusionThese results confirmed that the natural course of asymptomatic distal DVTs is benign, with no risk of leading to PE. Thus, distal DVTs could be allowed to remain untreated without chemical prophylaxis to prevent PE in Asian populations.     

Catheter-directed therapy for DVT after pancreas transplantation

INTRODUCTION: Iliac vein deep venous thrombosis (DVT) ipsilateral to the pancreas transplant can lead to severe leg edema and compromise graft function. Treatment modalities for iliac vein DVT in the pancreas transplant recipient are limited. METHODS: Medical records of patients receiving pancreas transplants at a single center from November 1989 to July 2003 were reviewed retrospectively, identifying patients with iliac vein DVT. There were 287 pancreas transplants performed during this time. Pancreas transplantation in all recipients was performed in the right iliac fossa with the arterial supply consisting of a donor iliac artery Y interposition graft. Systemic venous drainage was to the iliac vein. Exocrine drainage was enteric or to the bladder. RESULTS: Four (1.4%) cases of iliac DVT were identified. All patients manifested lower extremity edema ipsilateral to the pancreas transplant. DVT was detected by ultrasound on days 4, 5, 13, and 60 post-transplant. In all cases, the iliac vein caudad to the pancreatic venous anastomosis was noted to be stenotic. Management involved balloon dilatation and endovascular stent placement in one patient, thrombolysis with tissue plasma antigen (t-PA) followed by stent placement in one patient, and percutaneous mechanical thrombectomy in two patients. All patients had improvement in leg edema and two patients continue to have good pancreatic allograft function. CONCLUSIONS: Iliac DVT is a rare complication of pancreas transplantation that usually develops in an area of stenosis caudad to the pancreatic venous anastomosis. Catheter-based treatment modalities with use of endovascular stents for treatment of underlying stenoses can serve as an adjunct in treating these complications.     

The limitations of impedance plethysmography in the diagnosis of acute deep venous thrombosis

We reviewed our experience with impedance plethysmography (IPG) and duplex scanning in the diagnosis of acute deep venous thrombosis (DVT) to determine their respective accuracy and current role in our noninvasive vascular laboratory. During a recent 22-month period 1776 patients were evaluated in our laboratory for DVT. Sixty patients (64 limbs) underwent ascending venography within 48 hours of testing (49 limbs were evaluated by all three modalities). With the venograms used as the reference standard, B-mode scanning correctly identified the presence of acute thrombus in 24 of 27 limbs (88.8%) and the absence of thrombus in 31 of 34 limbs (91.2%), for an overall accuracy of 90.6%. IPG alone was less sensitive (75%) and less specific (44.8%), with an overall accuracy of only 57.1%. Twenty-eight IPGs were performed on patients with negative venous scans. Two positive IPGs were the result of chronic venous occlusion and two others detected clinically significant isolated iliac vein thrombi, but 13 patients had false positive IPGs. One false negative IPG occurred. The difference in the sensitivity of scan alone vs scan plus IPG was not significant (chi 2 = 0.045; difference not significant), but the decrease in specificity was chi 2 = 17.3; p less than 0.001). The rarity of isolated iliac vein thrombosis and the high false positive rate for IPG do not justify its continued use if B-mode venous scanning is available. Although positive scan results may be used confidently to institute therapy without the need for venography, in high-risk patients with a strong clinical suspicion of proximal DVT despite a negative scan venography should be obtained before withholding anticoagulation.