Stents in Common Iliac Vein Obstruction with Acute Ipsilateral Deep Venous Thrombosis: Early and Late Results

Catheter-directed thrombolysis with a continuous infusion of low-dose urokinase for non-acute deep venous thrombosis of the lower extremity

OBJECTIVE

We wanted to evaluate the feasibility of catheter-directed thrombolysis with a continuous infusion of low-dose urokinase for treating non-acute (less than 14 days) deep venous thrombosis of the lower extremity.

MATERIALS AND METHODS

The clinical data of 110 patients who were treated by catheter-directed thrombolysis with a continuous infusion of low-dose urokinase for lower extremity deep venous thrombosis was analysed. Adjunctive angioplasty or/and stenting was performed for the residual stenosis. Venous recanalization was graded by pre- and post-treatment venography. Follow-up was performed by clinical evaluation and Doppler ultrasound.

RESULTS

A total of 112 limbs with deep venous thrombosis with a mean symptom duration of 22.7 days (range: 15-38 days) were treated with a urokinase infusion (mean: 3.5 million IU) for a mean of 196 hours. After thrombolysis, stent placement was performed in 25 iliac vein lesions and percutaneous angioplasty (PTA) alone was done in five iliac veins. Clinically significant recanalization was achieved in 81% (90 of 112) of the treated limbs; complete recanalization was achieved in 28% (31 of 112) and partial recanalization was achieved in 53% (59 of 112). Minor bleeding occurred in 14 (13%) patients, but none of the patients suffered from major bleeding or symptomatic pulmonary embolism. During follow-up (mean: 15.2 months, range: 3-24 months), the veins were patent in 74 (67%) limbs. Thirty seven limbs (32%) showed progression of the stenosis with luminal narrowing more than 50%, including three with rethrombosis, while one revealed an asymptomatic iliac vein occlusion; 25 limbs (22%) developed mild post-thrombotic syndrome, and none had severe post-thrombotic syndrome. Valvular reflux occurred in 24 (21%) limbs.

CONCLUSION

Catheter-directed thrombolysis with a continuous infusion of low-dose urokinase combined with adjunctive iliac vein stenting is safe and effective for removal of the clot burden and for restoration of the venous flow in patients with non-acute lower extremity deep venous thrombosis.

Indications for catheter-directed thrombolysis in the management of acute proximal deep venous thrombosis

Deep vein thromboses (DVTs) cause significant morbidity and mortality in the general population. Oral anticoagulation therapy may reduce thrombus propagation but does not cause clot lysis and therefore does not prevent postthrombotic syndrome (PTS). Catheter-directed thrombolysis (CDT) can be used to treat DVTs as an adjunct to medical therapy, but there is no consensus defining exact indications. Current evidence suggests that CDT can reduce clot burden and DVT recurrence and consequently prevents the formation of PTS compared with systemic anticoagulation. Appropriate indications include younger individuals with acute proximal thromboses, a long life expectancy, and relatively few comorbidities. Limb-threatening thromboses may also be treated with CDT, although the subsequent mortality remains high. A number of randomized controlled trials are currently under way comparing the longer-term outcomes of CDT compared with anticoagulation alone. Initial reports suggest that venous patency and valvular function are better maintained after CDT. The effectiveness of combined pharmacomechanical thrombectomy and the role of vena cava filters need to be investigated further before strong recommendations can be made. The reported short-term outcomes following catheter-based intervention for DVT are encouraging in selected patients. Further evidence is required to establish long-term benefits and cost-effectiveness.

May-Thurner syndrome: case report and review of the literature involving modern endovascular therapy

May-Thurner syndrome is a rare clinical entity involving venous obstruction of the left lower extremity. Obstruction occurs secondary to compression of the left common iliac vein between the right common iliac artery and the underlying vertebral body. Current management largely involves endovascular therapy. A review was conducted of six studies containing at least five patients with May-Thurner syndrome treated by endovascular therapy. We compiled data on 113 patients, analyzing patient demographics, treatment details, and outcome. An 18-year-old female presented 1 week after the onset of left lower extremity pain and swelling. Duplex ultrasonography revealed extensive left-sided deep venous thrombosis (DVT). Thrombolysis followed by iliac vein stent placement restored patency to the venous system, with subsequent resolution of symptoms. Review of 113 patients revealed that the majority were females (72%) presenting with DVT (77%), most of which was acute in onset (73%). Therapy consisted of catheter-directed thrombolysis and subsequent stent placement in the majority of patients, resulting in a mean technical success of 95% and a mean 1-year patency of 96%. Endovascular therapy is the current mainstay of treatment for May-Thurner syndrome. Review of the current literature supports treatment via catheter-directed thrombolysis followed by stent placement with good early results.

Endovascular treatment for iliac vein compression syndrome: a comparison between the presence and absence of secondary thrombosis

Objective

To evaluate the value of early identification and endovascular treatment of iliac vein compression syndrome (IVCS), with or without deep vein thrombosis (DVT).

Materials and Methods

Three groups of patients, IVCS without DVT (group 1, n = 39), IVCS with fresh thrombosis (group 2, n = 52) and IVCS with non-fresh thrombosis (group 3, n = 34) were detected by Doppler ultrasonography, magnetic resonance venography, computed tomography or venography. The fresh venous thrombosis were treated by aspiration and thrombectomy, whereas the iliac vein compression per se were treated with a self-expandable stent. In cases with fresh thrombus, the inferior vena cava filter was inserted before the thrombosis suction, mechanical thrombus ablation, percutaneous transluminal angioplasty, stenting or transcatheter thrombolysis.

Results

Stenting was performed in 111 patients (38 of 39 group 1 patients and 73 of 86 group 2 or 3 patients). The stenting was tried in one of group 1 and in three of group 2 or 3 patients only to fail. The initial patency rates were 95% (group 1), 89% (group 2) and 65% (group 3), respectively and were significantly different (p = 0.001). Further, the six month patency rates were 93% (group 1), 83% (group 2) and 50% (group 3), respectively, and were similarly significantly different (p = 0.001). Both the initial and six month patency rates in the IVCS patients (without thrombosis or with fresh thrombosis), were significantly greater than the patency rates of IVCS patients with non-fresh thrombosis.

Conclusion

From the cases examined, the study suggests that endovascular treatment of IVCS, with or without thrombosis, is effective.

Symptomatic ileofemoral DVT after onset of oral contraceptive use in women with previously undiagnosed May-Thurner Syndrome

OBJECTIVE

May-Thurner syndrome is characterized by left common iliac obstruction secondary to compression of the left iliac vein by the right common iliac artery against the fifth-lumbar vertebra. This anatomic variant results in an increased incidence of left-sided deep venous thrombosis (DVT). Furthermore, while a preponderance of left-sided DVT has been demonstrated in women during pregnancy and oral contraceptive use, patients are not typically screened for this condition after developing a left-sided DVT. As anticoagulation alone is ineffective for DVT treatment in the setting of May-Thurner anatomy, more aggressive treatment is warranted. Failure to diagnosis this condition predisposes these women to the unnecessary risks of recurrent DVT and post-thrombotic syndrome.

METHODS

We present the occurrence of 7 adolescent patients with previously undiagnosed May-Thurner syndrome who presented with DVT after the initiation of oral contraceptive steroids (OCP) use. All 7 patients elected to proceed with mechanical thrombolysis/catheter based thrombolysis followed by endovascular stenting and were postoperatively treated with 6 months of warfarin.

RESULTS

Mean patient age was 18.3 +/- 3.3 years (range, 16-24 years). Mean time to presentation after initiation of OCP was 5 weeks (range, 2-10 weeks). Mean time to intervention was 16.8 days (range, 10-24 days). All patients were treated with mechanical thrombectomy. Our rate of intraoperative clot resolution was 100%. All 7 patients were treated with self expanding nitinol stents after angioplasty of the iliac vein stenosis with resolution of the stenotic segment. Primary stent patency is 100% (7/7). Mean follow-up time is 13 +/- 13.84 months (range, 6-42 months). There have been no long-term complications related to surgical treatment or anticoagulation. All 7 patients have experienced resolution of left leg swelling and pain and have no evidence of post-thrombotic syndrome or DVT recurrence to date.

CONCLUSIONS

Women on OCPs presenting with left-sided iliofemoral DVT should be screened for hypercoagulable disorders and underlying May-Thurner anatomy. Treatment of May-Thurner syndrome should include thrombolysis/thrombectomy and anticoagulation for current DVT in addition to angioplasty and stenting of the underlying obstruction.

Restoration of patency in iliofemoral deep vein thrombosis with catheter-directed thrombolysis does not always prevent post-thrombotic damage

OBJECTIVES

To evaluate the long-term results of catheter-directed thrombolysis (CDT) and the feasibility of stent placement for lower extremity deep vein thrombosis (DVT).

DESIGN & METHODS

Retrospective study of 34 patients (10 men and 24 women, mean age 55, S.D. 13 years) with lower extremity DVT underwent CDT at Seoul National University Hospital from January 1999 to October 2003. Patient characteristics, risk factors of DVT, extent of thrombosis, and short-term and long-term results of CDT and/or stent placement were analysed.

RESULTS

Mean follow-up times were 47 S.D. 16 months. The primary technical success rate was 97% (complete lysis 68%, partial 29%). During the follow-up periods 11 (32%) patients showed re-thrombosis. Sixteen (47%) of 34 patients showed chronic change of vessels during the follow-up periods. By Cox Proportional Hazard analysis, extent of thrombolysis was a statistically significant factor affecting the freedom of re-thrombosis and chronic change (P=0.008 and P=0.001). Nine (44%) of 21 deployed stents were obstructed, and the overall stent patency at 3 years was 56.7%. The only factor affecting the stent patency was stent length more than 6 cm (P=0.002, HR 13, 95% CI 2.7-59).

CONCLUSION

Long-term results of CDT are not satisfactory because of the high recurrence rate of DVT and it cannot prevent chronic post-thrombotic damage to the affected vessels despite long-term anticoagulation therapy. Careful long-term surveillance of the venous function is highly recommended after CDT.

Compression of the left common iliac vein in asymptomatic subjects and patients with left iliofemoral deep vein thrombosis

PURPOSE

To retrospectively evaluate compression of the left common iliac vein as demonstrated at computed tomography (CT) in patients with iliofemoral deep vein thrombosis due to iliac vein compression syndrome (IVCS) and compare compression ratios with those of asymptomatic subjects.

MATERIALS AND METHODS

Between March 2003 and June 2007, compression of the left common iliac vein by the right common iliac artery, as demonstrated with CT, in 34 patients (25 women and nine men; mean age, 51 years; age range, 21-79 years) with IVCS was retrospectively evaluated. Compression ratios were compared with those of 34 age- and sex-matched asymptomatic subjects. A t test was used to compare the compression ratios.

RESULTS

The percentages of compression of the left common iliac vein were 45%-100% (mean, 74% +/- 17) for patients with IVCS and 0%-68% (mean, 28% +/- 20) for control subjects (P < .05). Of the 34 patients with IVCS, 11 (32%) had less than 70% compression and 23 (68%) had at least 70% compression.

CONCLUSIONS

There was considerable overlap between the degree of compression in patients with IVCS and control subjects. Compression of the left common iliac vein was significantly more prominent in patients with lower extremity deep vein thrombosis due to IVCS when compared with control subjects. Compression in excess of 70% as demonstrated at CT can be helpful for identifying possible underlying IVCS in patients with a left lower extremity deep vein thrombosis.

Clinical predictors of recurrent venous thromboembolism: a single institute experience in Korea

INTRODUCTION

Racial disparities in incidence rate as well as risk factors for venous thromboembolism (VTE) exist between Asian and Western populations. Moreover, predictors for recurrent VTE were not identified in Asians. Thus, this study was undertaken to investigate risk factors for recurrent VTE events in Korean people.

MATERIALS AND METHODS

Three hundred-three patients newly diagnosed as VTE were enrolled from Seoul National University Hospital. Recurrence rate based on risk factors for VTE were investigated. Cumulative incidence of recurrent VTE was calculated by the Kaplan and Meier method. Independent predictors for VTE were determined using Cox proportional hazards model.

RESULTS

After a median follow-up of 44 months, 24 (8%) of 303 patients relapsed for a total observation time of 1,217 patient-year. Cumulative incidences of recurrent VTE were 3% at 1 year, 10% at 5 years, and 18% at 8 years. Independent predictors for recurrent VTE were presence of residual thrombosis (hazard ratio [HR]=3.1, 95% confidence interval [CI] 1.0-9.3; p=0.044), antiphospholipid syndrome (APS) (HR=4.3, 95% CI 1.0-19.0; p=0.052), and age 50 years or younger (HR=2.5, 95% CI 1.0-6.6; p=0.053) by multivariate analysis. Residual thrombosis and APS remained predictive of recurrence by the anticoagulation-period stratified analysis.

CONCLUSIONS

In contrast to Western populations, Korean patients with VTE had the lower recurrent rate. Extended anticoagulation is necessary for Korean patients with residual thrombosis or APS.

Massage-induced delayed venous stent migration

Catheter-directed therapies in chronic deep vein thromboses can help improve leg function by mechanically addressing residual obstruction in lower extremity or pelvic veins, although the reported use of stents in leg veins is relatively unusual. The author reports a case of this type with long-term patency and clinical success, culminating in asymptomatic delayed venous migration of a stent to the right atrium after 3 years. Open heart surgery was required to remove the embedded stent fragments. The attributed mechanism was deep tissue massage of the thigh.

Late results of surgical venous thrombectomy with iliocaval stenting

PURPOSE

Iliac vein occlusive disease leads to 73% of rethrombosis that occurs after venous thrombectomy when left untreated. The goal of this study is to present our long-term results of stenting of iliocaval occlusive lesions persisting after surgical venous thrombectomy.

METHODS

From November 1995 to April 2007, 29 patients (19 women), with a median age of 38 years, had surgical venous thrombectomy with creation of an arteriovenous fistula and angioplasty and stenting. All were admitted for acute (<10 days) deep venous thrombosis (DVT) involving the iliocaval segment, of which eight had concomitant acute pulmonary embolism. Six patients had a history of DVT (2 with previous venous thrombectomy), two were pregnant, and three had postpartum DVT. No patients had short- or mid-term life-threatening factors. The underlying lesion was left iliocaval compression (May-Thurner syndrome) in 22 patients, chronic left common iliac vein occlusion in 3, residual clot in 3, and compression of the left external iliac vein by the left internal iliac artery in 1.

RESULTS

Neither perioperative death nor pulmonary embolism occurred. Four early complications occurred after stenting (13.8%). Median hospital length of stay was 8 days (range, 5-22 days). Median follow-up was 63 months (range, 2-137 months). Three late complications occurred (10.3 %): one rethrombosis due to stent crushing during pregnancy and two restenosis, which were treated by iterative stenting. At the end of the follow-up, the median venous clinical severity score was 3 (range 1-12) and the venous disability score was 1 (range 0-2). Primary, assisted primary and secondary patency rates were, respectively, 79%, 86%, and 86% at 12, 60, and 120 months. Patients with patent iliocaval segments had significantly fewer infrainguinal obstructive lesions (4% vs 50%) and a higher rate of valvular competence (76% vs 0%) than those who experienced rethrombosis. Venous scores were also worse in patients with rethrombosis.

CONCLUSION

Stenting is a safe, efficient, and durable technique to treat occlusive iliocaval disease after venous thrombectomy. Its use can prevent most of the rethrombosis that occurs after venous thrombectomy without major adverse effects.

Initial and mid-term outcomes of pulse infusion thrombolysis using a unique pump system and stent placement for deep vein thrombosis

OBJECTIVE

The aim of this study was to evaluate the initial and mid-term results of pulse infusion thrombolysis (PIT) using a unique pump system and stent placement for proximal deep vein thrombosis (DVT) in Japanese.

METHODS

Among the patients who were admitted to our institute under diagnosis of proximal DVT between April 2001 and March 2005, 11 patients (4 men, mean age 61 years) who underwent PIT and angioplasty followed by stent placement were enrolled in this retrospective analysis. Urokinase or monteplase was used as a thrombolytic agent. Venous or stent patency was assessed by color Doppler ultrasound or enhanced computed tomography for a mean follow-up duration of 54 months.

RESULTS

Sites of thrombus were left lower limbs in 10 cases and left upper limb in one case. Initial technical (complete venous flow recovery) and clinical (disappearance of pain and swelling of diseased leg or arm) success was achieved in all patients. Two of 11 patients showed stent occlusion with leg swelling and pain one month later and 3 years later, respectively. These patients had associated protein S deficiency.

CONCLUSION

PIT and stent deployment for DVT is safe and effective with favorable initial and mid-term clinical results and without major complications in Japanese, except for cases of congenital coagulation abnormality.

Factors associated with outcome after interventional treatment of symptomatic iliac vein compression syndrome

BACKGROUND

Iliac vein compression syndrome (IVCS) results from compression of the left iliac vein by the overlying right iliac artery against the pelvic brim. In many cases, patients are symptomatic. In symptomatic cases, management consists of angioplasty and stenting. Although therapy is often initially successful, factors associated with long-term outcome have been poorly defined. The purpose of this study was to identify factors associated with stent patency.

METHODS

The medical records of all patients who underwent iliac vein percutaneous transluminal angioplasty and stenting from January 1996 to December 2006 for symptomatic IVCS were reviewed retrospectively. There were 50 women and 8 men, with a mean age of 42 years (median, 39 years; range, 17-71 years). Primary, assisted primary, and secondary patency rates were determined. Patient characteristics and clinical variables were evaluated by univariate and multivariate analysis to determine association with vein patency.

RESULTS

Symptoms consisted of lower extremity swelling (81%) and lower extremity pain (67%). Iliac vein obstruction was treated with pharmacologic thrombolysis (31% of patients) and mechanical thrombus fragmentation (17% of patients). The primary, assisted primary, and secondary patency rates of angioplasty/stenting were 74.1%, 79.7%, and 85.8% at 1 year and 38.1%, 62.8%, and 73.8% at 5 years, respectively. Using a Cox proportional risk model, male sex (hazard ratio, 6.5; P = .001), recent trauma (hazard ratio, 5.3; P = .001), and age younger than 40 years (hazard ratio, 3.8; P = .015) were associated with decreased primary patency. In the absence of any risk factors, primary patency was 94.4% at 1 year and 63.0% at 5 years, decreasing to 28.6% and 0% for two or more risk factors.

CONCLUSIONS

Patency rates for iliac vein percutaneous transluminal angioplasty and stenting in patients with IVCS can potentially be predicted on the basis of a multivariate model. Assessing risk factors allows for patient stratification and appropriate clinical decision making. Prospective validation of these variables is necessary.

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.

Mechanical Thrombectomy of Acute Iliofemoral Deep Vein Thrombosis with Use of an Arrow-Trerotola Percutaneous Thrombectomy Device

PURPOSE

To evaluate the immediate and 1-year clinical outcomes of mechanical thrombectomy with use of the Arrow-Trerotola percutaneous thrombectomy device (PTD) with or without low-dose urokinase in the treatment of acute iliofemoral deep vein thrombosis (DVT).

MATERIALS AND METHODS

Mechanical thrombectomy with the PTD was performed in 25 patients with acute iliofemoral DVT. Thrombolytic therapy with low-dose urokinase was used in all patients without contraindications (n = 20). Other therapies used in combination included inferior vena cava filter insertion (n = 5), sheath aspiration thrombectomy (n = 25), and angioplasty and stent placement (n = 20).

RESULTS

Initial technical and clinical success was achieved in all cases. In the 20 patients who had no contraindications to the use of urokinase, the dosage of urokinase did not exceed 1 million IU (range, 360,000-1,000,000 IU; mean, 640,000 IU). The mean time of urokinase infusion was 16 hours (range, 12-20). In five patients who had a contraindication to the use of urokinase, mechanical thrombectomy with the PTD was successful without the use of urokinase. There were no major complications. Primary patency of the stent-implanted common iliac vein segment was achieved at 1 year in 17 of 20 patients (85%). The overall 1-year clinical success rate was 92% (23 of 25 patients). Valvular insufficiency occurred in two patients (8%).

CONCLUSION

The PTD is an effective mechanical thrombectomy device in the treatment of acute iliofemoral DVT with or without adjunctive urokinase thrombolysis.