Adjunctive Percutaneous Mechanical Thrombectomy for Lower-extremity Deep Vein Thrombosis: Clinical and Economic Outcomes

The results of aspiration thrombecomy in the endovascular treatment for iliofemoral deep vein thrombosis

Purpose

The aim of this study is to evaluate the results of aspiration thrombectomy (AT) in the endovascular treatment for iliofemoral deep vein thrombosis (DVT) through the comparison of catheter directed thrombolysis (CDT) alone group and CDT with AT group.

Methods

From November 2001 to April 2011, 100 patients received endovascular treatment with CDT alone or CDT with AT for iliofemoral DVT at Yeungnam University Medical Center. We compared procedure, clinical outcomes and complications between the two groups.

Results

The mean age of patients was 60.48 ± 14.57 years. The patients consisted of 41 men and 59 women. CDT alone and CDT with AT were performed in 29 and 71 patients, respectively. The mean procedural time of the CDT-alone group was longer than the CDT with AT group (P < 0.001) and dose of urokinase used during the procedure significantly decreased in the CDT with AT group (P < 0.001). There were no statistically significant differences in clinical outcomes between the two groups. Cases of pulmonary embolism was not noted in each group in our series, but entrapped thrombus during procedure was noted in 6 of 37 in the CDT with AT group and 0 of 9 in the CDT-alone group among 46 patients with prophylactic inferior vena cava (IVC) filter insertion.

Conclusion

In conclusion, CDT with AT is safe and effective for the treatment of an acute iliofemoral DVT. In AT treatment, prophylactic IVC filter insertion should be considered for the prevention of pulmonary embolism by floating thrombi.

Deep vein thrombosis: current status and nanotechnology advances

Deep vein thrombosis (DVT) affects up to 2 million people in the United States, and worldwide incidence is 70 to 113 cases per 100,000 per year. Mortality from DVT is often due to subsequent pulmonary embolism (PE). Precise diagnosis and treatment is thereby essential for the management of DVT. DVT is diagnosed by a thorough history and physical examination followed by laboratory and diagnostic tests. The choice of laboratory and diagnostic test is dependent on clinical pretest probability. Available laboratory and diagnostic techniques mainly involve D-dimer test, ultrasound, venography, and magnetic resonance imaging. The latter two diagnostic tools require high doses of contrast agents including either radioactive or toxic materials. The available treatment options include lifestyle modifications, mechanical compression, anticoagulant therapy, inferior vena cava filter, and thrombolysis/thrombolectomy. All of these medical and surgical treatments have serious side effects including improper clot clearance and increased risk of hemorrhage occurrence. Therefore, research in this field has recently focused on the development of non-invasive and accurate diagnostics, such as ultrasound enhanced techniques and molecular imaging methods, to assess thrombus location and its treatment course. The frontier of nanomedicine also shows high prospects in tackling DVT with efficient targeted drug delivery. This review describes the pathology of DVT along with successive medical problems such as PE and features a detailed listing of various diagnostic and therapeutic modalities that have been in use and are under development.

Management of proximal deep vein thrombosis

Iliofemoral DVT constitutes approximately 20-25% of lower limb DVT and represents a specific subgroup of patients at highest risk for post-thrombotic syndrome (PTS). Anticoagulation alone has no significant thrombolytic activity and has not impact on PTS prevention. Early thrombus removal has reduced PTS in uncontrolled reports and reviews but major trials are awaited. The optimal timing for treatment appear to be thrombus <2 weeks old and, methods for thrombus removal include direct open or suction thrombectomy, catheter directed thrombolysis (CDT), with or without percutaneous mechanical thrombectomy (PMT) devices. Three principle types of PMT device are in use (rotational, rheolytic and ultrasound enhanced devices) and are combined with CDT in pharmocomechanical thrombolysis (PhMT) to enhance early thrombus removal. These devices have individual device specific attributes and side effects that are additional to the bleeding complications of thrombolysis. A number of additional interventions may be utilised to the improve results of CDT and PhMT. IVC filter deployment to reduce periprocedural PE, is supported by little evidence unless an indication for its use already exists. However, balloon venoplasty and vein stents undoubtedly vein patency after treatment. Early thrombus removal comes with additional upfront costs derived from devices, imaging and critical care bed usage. However, significant potential savings from reduction in PTS and rethrombosis rates may reduce overall societal costs. This review focuses on iliofemoral thrombosis, however, the less commonly encountered but clinically important subclavian vein thrombosis is also discussed.

Interventional approaches to deep vein thrombosis

The last decade has seen increased use of aggressive, catheter-based methods of treating deep vein thrombosis (DVT). In this article, we outline the risks, benefits, and uncertainties surrounding endovascular DVT therapies, describe clinical situations in which endovascular treatment options should reasonably be considered, and update the reader on new outcome data that pertains to catheter-based DVT interventions. Endovascular thrombolytic therapy is reasonable to perform for selected patients with DVT causing acute limb-threatening circulatory compromise, acute inferior vena cava occlusion, or acute iliofemoral DVT for the purposes of limb salvage and relief of presenting DVT symptoms, and appears likely to prevent post-thrombotic syndrome (PTS) in patients with proximal DVT. A multicenter randomized trial, the ATTRACT Study, is currently underway in the United States to determine whether pharmacomechanical catheter-directed thrombolysis (PCDT) is sufficiently safe and effective to be recommended for routine use in proximal DVT patients. Selected patients with established moderate-to-severe PTS in association with an occluded iliac vein or a refluxing saphenous vein may also be amenable to endovascular intervention to reduce venous hypertension, alleviate symptoms, and improve limb function and quality of life. Pending the results of further studies, an individualized approach to patient selection for interventional DVT therapies is recommended.

pharmacomechanical Thrombectomy for Early Thrombus Removal

Objectives:

To review the current literature on the outcomes of pharmacomechanical thrombectomy (PMT) for early thrombus removal in patients with venous thromboembolism (VTE).

Methods:

We searched the MEDLINE database and performed a manual search of the references of selected articles to select reports reporting the outcomes of PMT alone and PMT compared to catheter-direct thrombolysis (CDT). Outcomes of interest included clot lysis rate, incidence of pulmonary embolism, major bleeding, recurrent deep vein thrombosis, number of venograms needed and amount of lytic utilized.

Results

We found nine articles that reported outcomes of PMT. Three devices were utilized for PMT, the Angiojet, Trellis and Helix. Different thrombolytics were used to facilitate thrombus removal including urokinase, reteplase, tecneteplase, and tissue plasminogen activator (t-PA). Complete and partial thrombus removal were achieved in up to 84% and 64% and 81% and 59% of the limbs treated with PMT and CDT alone, respectively. Data on PE and bleeding risk after PMT compared to CDT are scarce. The duration of the thrombolysis process, amount of lytics and number of venograms were substantially reduced in the patients who had PMT compared to those who underwent CDT alone. Two articles evaluated the obstacles that limit the indication of PMT in patients with VTE.

Conclusion:

VTE is a prevalent burden in Western societies. The rationale of early thrombus is to reduce valvular damage and improve venous patency in order to reduce the risk of PTS. PMT is a feasible, safe and faster alternative to expedite the thrombolysis process in patients with VTE.

Rationale and Indications for Aggressive Early Thrombus Removal

Randomized clinical trials have defined anticoagulation with unfractionated or low-molecular-weight heparin followed by warfarin as a standard therapy for acute deep venous thrombosis (DVT). Such treatment is highly effective in preventing recurrent venous thromboembolism with a low risk of bleeding, but provides imperfect protection against development of the post-thrombotic syndrome. Several strategies of early thrombus removal, including surgical venous thrombectomy, catheter-directed thrombolysis and pharmacomechanical thrombectomy have been developed with the goal of reducing the incidence of the post-thrombotic syndrome by restoring venous patency and preserving valvular function. Although clinical judgement and a consideration of the individual patient's medical condition and values are required, early thrombus removal strategies should be considered in selected patients with phlegmasia cerulea dolens and those with a first episode of acute iliofemoral thrombosis of less than 14 days duration.

[The role of thrombolysis in the clinical management of deep vein thrombosis]

Acute Deep Venous Thrombosis (DVT) therapies have been judged primarily on their ability to prevent symptomatic pulmonary embolism, early thrombus progression, and recurrent VTE. The cornerstones of current management of DVT, supported by the 2008 American College of Chest Physicians (ACCP) guidelines, are the routine use of anticoagulant therapy, graduated elastic compression stockings, and early ambulation. For selected appropriate patients with extensive acute proximal DVT, while the French recommendations (Afssaps 2009) still consider thrombolysis not indicated, ACCP guidelines now suggest in-situ thrombolysis in addition to anticoagulation to reduce the risk of subsequent postthrombotic syndrome (PTS) and recurrent DVT (Grade 2 B recommendation). Contemporary invasive endovascular treatments, called pharmacomechanical treatment, mitigate the drawbacks (major bleeding) historically associated with systemic thrombolytic approaches, by means of intra-thrombus delivery of drugs, followed by mechanical dispersion to accelerate lysis and then aspiration of remaining drug and clot debris. The proof of concept for the "open vein" hypothesis - that a strategy of early thrombus removal can reduce the incidence of PTS long term - comes incrementally and randomized trials (ATTRACT trial with a 2016 target completion date) are currently under way and might lead to a shift of the paradigms of the management of acute DVT focused on active thrombus removal.

Interventional treatment of venous thromboembolism: a review

Venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE), is the third most common cardiovascular disease after coronary artery disease and cerebrovascular disease and is responsible for significant morbidity and mortality in the general population. Full dose anticoagulation is the standard therapy for VTE, both for the acute and the long-term phase. The latest guidelines of the American College of Chest Physicians recommend treatment with a full-dose of unfractioned heparin (UFH), low-molecular-weight-heparin (LMWH), fondaparinux, vitamin K antagonist (VKA) or thrombolysis for most patients with objectively confirmed VTE. Catheter-guided thrombolysis and trombosuction are interventional approaches that should be used only in selected populations; interruption of the inferior vena cava (IVC) with a filter can be performed to prevent life-threatening PE in patients with VTE and contraindications to anticoagulant treatment, bleeding complications during antithrombotic treatment, or VTE recurrences despite optimal anticoagulation. In this review we summarize the currently available literature regarding interventional approaches for VTE treatment (vena cava filters, catheter-guided thrombolysis, thrombosuction) and we discuss current evidences on their efficacy and safety. Moreover, the appropriate indications for their use in daily clinical practice are reviewed.

Thrombolysis for deep venous thrombosis

The key questions addressed in this summary are whether clot removal should be part of the preferred therapy for patients with acute deep venous thrombosis (DVT), and whether there is evidence that a strategy of thrombus removal offers better outcomes for patients than anticoagulation alone. Evidence is defined as an outward sign or something that furnishes proof. Evidence in medicine is not limited to direct, blinded comparisons of one form of treatment compared with another but rather the body of knowledge that provides insight to clinicians to offer patient care. Evidence-based medicine follows from information available to form the foundation for the use of a treatment for a specific disease. Reports of strategies of thrombus removal for acute DVT, especially in patients with iliofemoral DVT, consistently demonstrate improved outcomes relative to postthrombotic morbidity. This summary reviews the evidence supporting this strategy as the preferred initial management of patients with extensive proximal DVT.

The role of thrombolysis in the clinical management of deep vein thrombosis

The cornerstones of current management of deep vein thrombosis (DVT) are the routine use of anticoagulant therapy, graduated elastic compression stockings, and early ambulation. Thrombolytic therapy was previously reserved only for patients with life-, limb-, or organ-threatening complications. However, the postthrombotic syndrome has been increasingly recognized as a frequent and serious long-term complication of DVT. In parallel, endovascular thrombolytic methods have evolved considerably in recent years, prompting discussion and controversy as to whether they should be more liberally used. In some centers, pharmacomechanical catheter-directed thrombolysis is now routinely used in the treatment of acute iliofemoral DVT. Randomized trials are currently under way to determine when the use of pharmacomechanical catheter-directed thrombolysis is appropriate in patients presenting with acute proximal DVT.

Management of massive and submassive pulmonary embolism, iliofemoral deep vein thrombosis, and chronic thromboembolic pulmonary hypertension: a scientific statement from the American Heart Association

Venous thromboembolism (VTE) is responsible for the hospitalization of >250 000 Americans annually and represents a significant risk for morbidity and mortality. Despite the publication of evidence-based clinical practice guidelines to aid in the management of VTE in its acute and chronic forms, the clinician is frequently confronted with manifestations of VTE for which data are sparse and optimal management is unclear. In particular, the optimal use of advanced therapies for acute VTE, including thrombolysis and catheter-based therapies, remains uncertain. This report addresses the management of massive and submassive pulmonary embolism (PE), iliofemoral deep vein thrombosis (IFDVT),and chronic thromboembolic pulmonary hypertension (CTEPH). The goal is to provide practical advice to enable the busy clinician to optimize the management of patients with these severe manifestations of VTE. Although this document makes recommendations for management, optimal medical decisions must incorporate other factors, including patient wishes, quality of life, and life expectancy based on age and comorbidities. The appropriateness of these recommendations for a specific patient may vary depending on these factors and will be best judged by the bedside clinician.

Deep venous thrombosis: the opportunity at hand

OBJECTIVE

The use of imaging-guided treatments for deep venous thrombosis (DVT) is accelerating. Increased appreciation of the impact of postthrombotic syndrome on DVT patients' quality of life and advances in thrombolytic methods have together sparked an unprecedented degree of interdisciplinary collaboration in developing contemporary DVT treatment guidelines and a pivotal clinical trial to establish the risk-benefit ratio of interventional DVT therapy.

CONCLUSION

Radiologists should improve their DVT education, support ongoing clinical trials, and collaborate with DVT-focused nonradiologists in their institutions.

Antithrombotic therapy for venous thromboembolic disease: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition)

This chapter about treatment for venous thromboembolic disease is part of the American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Grade 1 recommendations are strong and indicate that the benefits do or do not outweigh risks, burden, and costs. Grade 2 suggests that individual patient values may lead to different choices (for a full understanding of the grading, see "Grades of Recommendation" chapter). Among the key recommendations in this chapter are the following: for patients with objectively confirmed deep vein thrombosis (DVT) or pulmonary embolism (PE), we recommend anticoagulant therapy with subcutaneous (SC) low-molecular-weight heparin (LMWH), monitored IV, or SC unfractionated heparin (UFH), unmonitored weight-based SC UFH, or SC fondaparinux (all Grade 1A). For patients with a high clinical suspicion of DVT or PE, we recommend treatment with anticoagulants while awaiting the outcome of diagnostic tests (Grade 1C). For patients with confirmed PE, we recommend early evaluation of the risks to benefits of thrombolytic therapy (Grade 1C); for those with hemodynamic compromise, we recommend short-course thrombolytic therapy (Grade 1B); and for those with nonmassive PE, we recommend against the use of thrombolytic therapy (Grade 1B). In acute DVT or PE, we recommend initial treatment with LMWH, UFH or fondaparinux for at least 5 days rather than a shorter period (Grade 1C); and initiation of vitamin K antagonists (VKAs) together with LMWH, UFH, or fondaparinux on the first treatment day, and discontinuation of these heparin preparations when the international normalized ratio (INR) is > or = 2.0 for at least 24 h (Grade 1A). For patients with DVT or PE secondary to a transient (reversible) risk factor, we recommend treatment with a VKA for 3 months over treatment for shorter periods (Grade 1A). For patients with unprovoked DVT or PE, we recommend treatment with a VKA for at least 3 months (Grade 1A), and that all patients are then evaluated for the risks to benefits of indefinite therapy (Grade 1C). We recommend indefinite anticoagulant therapy for patients with a first unprovoked proximal DVT or PE and a low risk of bleeding when this is consistent with the patient's preference (Grade 1A), and for most patients with a second unprovoked DVT (Grade 1A). We recommend that the dose of VKA be adjusted to maintain a target INR of 2.5 (INR range, 2.0 to 3.0) for all treatment durations (Grade 1A). We recommend at least 3 months of treatment with LMWH for patients with VTE and cancer (Grade 1A), followed by treatment with LMWH or VKA as long as the cancer is active (Grade 1C). For prevention of postthrombotic syndrome (PTS) after proximal DVT, we recommend use of an elastic compression stocking (Grade 1A). For DVT of the upper extremity, we recommend similar treatment as for DVT of the leg (Grade 1C). Selected patients with lower-extremity (Grade 2B) and upper-extremity (Grade 2C). DVT may be considered for thrombus removal, generally using catheter-based thrombolytic techniques. For extensive superficial vein thrombosis, we recommend treatment with prophylactic or intermediate doses of LMWH or intermediate doses of UFH for 4 weeks (Grade 1B).

Safety of catheter-directed thrombolysis for deep venous thrombosis in cancer patients

BACKGROUND

The current study was conducted to demonstrate that catheter-directed thrombolysis for upper and lower extremity deep vein thrombosis is equally safe in patients with and without cancer.

METHODS

A retrospective cohort of consecutive patients with acute iliofemoral or brachiosubclavian deep vein thrombosis treated with catheter-directed thrombolysis was identified. Demographic characteristics and clinical outcomes were compared between patients with cancer and without cancer.

RESULTS

Catheter-directed thrombolysis was used to treat 202 limbs in 178 patients (75 limbs in 61 cancer patients and 127 limbs in 117 patients without cancer). The mean treatment duration for patients with cancer (29.7 +/- 21.2 hours) and without cancer (28.8 +/- 22.2 hours) was similar (P = .7774). Catheter-directed thrombolysis achieved grade III clot lysis in a similar proportion of cancer patients (50 of 75 limbs, 66.7%) and patients without cancer (82 of 127 limbs, 64.6%; P = .7619). Grade II clot lysis also was achieved in equal numbers of patients with (20 of 75 limbs, 26.7%) and without cancer (34 of 127 limbs, 26.8%; P = .9872). Three cancer patients (4.9%) and four noncancer patients (3.4%) experienced major bleeding during catheter-directed thrombolysis (P = .6924). Pulmonary embolism occurred in 1.6% (1 of 61) of cancer patients and in 1.7% (2 of 117) of patients without cancer (P = .9999) during catheter-directed thrombolysis. Patients aged > or =70 years had an increased risk of major bleeding.

CONCLUSION

Percutaneous catheter-directed thrombolysis is equally safe for patients with and without cancer who have acute symptomatic deep vein thrombosis.

Treatment of symptomatic lower extremity acute deep venous thrombosis: role of mechanical thrombectomy

Systemic anticoagulation with heparin or its unfractionated derivatives followed by warfarin therapy has been the mainstay of treatment in patients with lower extremity deep venous thrombosis (DVT). Although heparin is an effective treatment modality in preventing thrombus propagation, it provides minimal therapeutic effect in dissolving preexisting venous thrombus. The clinical consequence of DVT, owing in part to loss of venous endothelial and valvular function, is postphlebitic syndrome or chronic venous insufficiency. Current advances in endovascular therapy have resulted in various endovascular thrombectomy systems that can effectively remove a large venous thrombus burden, which may represent a potential advantage of preserving venous valvular function and thereby reduce the likelihood of postphlebitic syndrome. In this article, we review a variety of surgical and interventional methods in venous thrombus removal. Current treatment modalities using mechanical thrombectomy devices and pharmacomechancial thrombectomy strategy are also discussed.

Pharmacomechanical Thrombectomy of Acute Deep Vein Thrombosis with the Trellis-8 Isolated Thrombolysis Catheter

PURPOSE

To evaluate the performance of the Trellis-8 isolated thrombolysis catheter during single-session pharmacomechanical thrombectomy (PMT) combined with low-dose thrombolysis with tissue plasminogen activator (TPA) in the treatment of patients with acute deep vein thrombosis (DVT) and multiple comorbidities.

MATERIALS AND METHODS

Retrospective analysis was performed of 19 consecutive patients with acute above-knee DVT treated by PMT with the Trellis device followed by venous angioplasty and stent placement. Isolated thrombolysis with low-dose TPA was used with all patients. Concurrent therapies included retrievable inferior vena cava filter insertion (n = 4). The primary endpoint was restoration of rapid inline venous flow; the secondary endpoint was thrombus clearance.

RESULTS

Restoration of rapid inline venous flow was achieved in all cases; thrombus removal was less than 50% in one case (4%), 50%-95% in 18 cases (82%), and at least 95% in three cases (14%). The median administered dose of TPA was 13.4 mg per patient. The mean treatment time was 91 minutes per limb (range, 61-129 min), with a mean of 21 minutes per thrombosed segment (range, 8-31 min). There were no major complications. Primary patency rate of the treated venous segments at 2 days was 86% (n = 19) and the primary assisted patency rate was 100% at 30 days. Two patients died of advanced malignancy at 17 and 24 days.

CONCLUSIONS

The Trellis system was an effective method for the treatment of acute DVT. Based on the present data, the Trellis system could prove to be a safe and feasible single-session PMT method for the treatment of acute DVT in a broader patient population and warrants further investigation in a large-scale study.