Pharmacomechanical thrombectomy for iliofemoral deep vein thrombosis

Calf deep veins are safe and feasible accesses for the endovascular treatment of acute lower extremity deep vein thrombosis

This study was designed to assess the optimal access route for the endovascular treatment of acute lower extremity deep vein thrombosis. This was a retrospective analysis of patients with acute lower extremity deep venous thrombosis who underwent endovascular treatment from February 2009 to December 2020. Patients underwent non-direct calf deep vein puncture (NDCDVP) from February 2009 to December 2011 and direct calf deep vein puncture (DCDVP) from January 2012 to December 2020. Catheter directed thrombolysis (CDT) was used to treat all patients in the NDCDVP group, whereas patients in the DCDVP group were treated with CDT or the AngioJet rhyolitic thrombectomy system. In patients exhibiting iliac vein compression syndrome, the iliac vein was dilated and implanted with a stent. Technical success rates and perioperative complication rates were compared between these two treatment groups. The NDCDVP group included 83 patients (40 males, 43 females) with a mean age of 55 ± 16 years, while the DCDVP group included 487 patients (231 males. 256 females) with a mean age of 56 ± 15 years. No significant differences were observed between these groups with respect to any analyzed clinical characteristics. The technical success rates in the NDCDVP and DCDVP groups were 96.4 and 98.2%, respectively (P > 0.05). In the NDCDVP group, the small saphenous vein (SSV)or great saphenous vein (GSV)were the most common access routes (77.1%, 64/83), whereas the anterior tibial vein (ATV) was the most common access route in the DCDVP group (78.0%, 380/487), followed by the posterior tibial vein (PTV) and peroneal vein (PV)(15.6% and 6.4%, respectively). Relative to the NDCDVP group, more patients in the DCDVP group underwent the removal of deep vein clots below the knee (7.2% [6/83] vs. 24.2% [118/487], P < 0.001). Moreover, relative to the NDCDVP group, significantly lower complication rates were evident in the DCDVP group (local infection: 10.8% vs. 0.4%, P < 0.001; local hematoma: 15.7% vs. 1.0%, P < 0.001). The position change rate was also significantly lower in the DCDVP group relative to the NDCDVP group (0% [0/487] vs. 60.2% [50/83], P < 0.001). The calf deep veins (CDVs) represent a feasible and safe access route for the endovascular treatment of lower extremity deep vein thrombosis.

Venous Intervention

Any overview of the treatment of venous disease should begin with a brief examination of its history. From the first rudimentary attempt at venous thrombectomy in the early 1920s to the evolution of percutaneous and mechanical thrombectomy and endovascular stents in the 21st century. It is the aim of this review to provide a comprehensive summary of the state of the art of venous disease treatment at the turn of the new century.

Antiplatelet agents for the treatment of deep venous thrombosis

BACKGROUND

Antiplatelet agents may be useful for the treatment of deep venous thrombosis (DVT) when used in addition to best medical practice (BMP), which includes anticoagulation, compression stockings, and clinical care such as physical exercise, skin hydration, etc. Antiplatelet agents could minimise complications such as post-thrombotic syndrome (PTS) and pulmonary embolism (PE). They may also reduce the recurrence of the disease (recurrent venous thromboembolism (recurrent VTE)). However, antiplatelet agents may increase the likelihood of bleeding events.

OBJECTIVES

To assess the effects of antiplatelet agents in addition to current BMP compared to current BMP (with or without placebo) for the treatment of DVT.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase and CINAHL databases and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 7 December 2021. The review authors searched LILACS and IBECS databases (15 December 2021) and also checked the bibliographies of included trials for further references to relevant trials, and contacted specialists in the field, manufacturers and authors of the included trials.

SELECTION CRITERIA

We considered randomised controlled trials (RCTs) examining antiplatelet agents compared to BMP following initial standard anticoagulation treatment for DVT. We included studies where antiplatelet agents were given in addition to current BMP compared to current BMP (with or without placebo) for the treatment of DVT (acute: treatment started within 21 days of symptom onset; chronic: treatment started after 21 days of symptom onset). We evaluated only RCTs where the antiplatelet agents were the unique difference between the groups (intervention and control).

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures. Two review authors independently extracted data and assessed risk of bias of the trials. Any disagreements were resolved by discussion with a third review author. We calculated outcome effects using risk ratio (RR) or mean difference (MD) with a 95% confidence interval (CI) and the number needed to treat to benefit (NNTB).

MAIN RESULTS

We included six studies with 1625 eligible participants, with data up to 37.2 months of follow-up. For one preplanned comparison (i.e. antiplatelet agents plus BMP versus BMP plus placebo) for acute DVT we identified no eligible studies for inclusion. In acute DVT, antiplatelet agents plus BMP versus BMP alone was assessed by one study (500 participants), which reported on four outcomes until 6 months of follow-up. There were no deaths and no cases of major bleeding reported. The participants who received antiplatelet agents showed a lower risk of PTS (RR 0.74, 95% CI 0.61 to 0.91; 1 study, 500 participants; very low-certainty evidence). The control group presented a lower risk of adverse events compared to the intervention group (RR 2.88, 95% CI 1.06 to 7.80; 1 study, 500 participants; very low-certainty evidence). This study did not provide information for recurrent VTE or PE. In chronic DVT, antiplatelet agents plus BMP versus BMP alone was assessed by one study (224 participants). The study authors reported four relevant outcomes, three of which (major bleeding, mortality and adverse events) showed no events during the 3 years of follow-up. Therefore, an effect estimate could only be reported for recurrent VTE, favouring antiplatelet agents plus BMP versus BMP alone (RR 0.12, 95% CI 0.05 to 0.34; 1 study, 224 participants; very low-certainty evidence). For the outcomes PE and PTS, this study did not present information which could be used for analysis. In chronic DVT, antiplatelet agents plus BMP versus BMP plus placebo was assessed by four studies (901 participants). The meta-analysis of this pooled data showed a lower risk of recurrent VTE for the antiplatelet agents group (RR 0.65, 95%, CI 0.43 to 0.96; NNTB = 14; low-certainty evidence). For major bleeding, we found no clear difference between placebo and intervention groups until 37.2 months of follow-up (RR 0.98, 95% CI 0.29 to 3.34; 1 study, 583 participants; moderate-certainty evidence). In PE fatal/non-fatal outcome, we found no clear difference with the use of antiplatelet agents (RR 0.52, 95% CI 0.23 to 1.14; 1 study, 583 participants; moderate-certainty evidence). For all-cause mortality, the overall effect of antiplatelet agents did not differ from the placebo group (RR 0.48, 95% CI 0.21 to 1.06; 3 studies, 649 participants; moderate-certainty evidence). The adverse events outcome did not show a clear difference (RR 1.57, 95% CI 0.34 to 7.19; 2 studies, 621 participants; moderate-certainty evidence). There is no assessment of PTS in these studies. We downgraded the certainty of evidence for risk of bias, indirectness, imprecision and publication bias.

AUTHORS' CONCLUSIONS

In chronic DVT settings, following the initial standard treatment with anticoagulants, there is low-certainty evidence that antiplatelet agents in addition to BMP may reduce recurrent VTE, (NNTB = 14) when compared to BMP plus placebo. Moderate-certainty evidence shows no clear difference in adverse events, major bleeding and PE when antiplatelet agents are used in addition to BMP compared to BMP plus placebo. In acute and chronic DVT settings, following the initial standard treatment with anticoagulants, we can draw no conclusions for antiplatelet agents in addition to BMP compared to BMP alone due to very low-certainty evidence.  Trials of high methodological quality, that are large and of sufficient duration to detect significant clinical outcomes are needed. Trials should ideally last more than 4 years in order to estimate the long-term effect of antiplatelet agents. Trials should include people with acute and chronic DVT and provide relevant individual data, such as the outcome for each index event (DVT or PE), the use of an inferior vena cava (IVC) filter, whether the DVT is provoked or unprovoked, and the age of participants.

Invasive and Pharmacological Treatment of Deep Vein Thrombosis: a Scoping Review

The annual occurrence of venous thromboembolism (VTE) is 300,000-600,000 cases in the United States and 700,000 in Europe. VTE includes deep venous thrombosis (DVT) of upper or lower extremities, superior and inferior vena cava thrombosis, and pulmonary embolism (PE) as well. The primary treatment of DVT includes oral anticoagulation to prevent the progression of the thrombus and decrease the risk of pulmonary embolism. Depending on the symptoms, more invasive treatments can be applied to target the iliofemoral thrombus and its removal. However, less emphasis is given to acute symptomatology, early recovery of function, quality of life improvement, and the individualized likelihood of developing post-thrombotic syndrome. While invasive therapy has been used to enhance the acute management of iliofemoral DVT, our knowledge about the overall outcomes associated with the invasive treatment of VTE is still limited. In this review, we illustrate the available data on pharmacological and endovascular management of iliofemoral VTE, including therapies such as catheter-directed thrombolysis (CDT), mechanical thrombectomy (PMT), and pharmacomechanical catheter-directed thrombolysis (PCDT).

Anticoagulation Treatment in Venous Thromboembolism: Options and Optimal Duration

Venous thromboembolism (VTE), clinically presenting as deep-vein thrombosis (DVT) or pulmonary embolism (PE), constitutes a major global healthcare concern with severe complications, long-term morbidity and mortality. Although several clinical, genetic and acquired risk factors for VTE have been identified, the molecular pathophysiology and mechanisms of disease progression remain poorly understood. Anticoagulation has been the cornerstone of therapy for decades, but there still are uncertainties regarding primary and secondary VTE prevention, as well as optimal therapy duration. In this review we discuss the role of factor Xa in coagulation cascade and the different choices of anticoagulation therapy based on patients' predisposing risk factors and risk of event recurrence. Further, we compare newer agents to traditional anticoagulation treatment, based on most recent studies and guidelines.

AngioJet Thrombectomy Versus Catheter-Directed Thrombolysis for Lower Extremity Deep Vein Thrombosis: A Meta-Analysis of Clinical Trials

Early catheter-directed thrombolysis (CDT) for lower extremity deep vein thrombosis (LEDVT) can reduce post-thrombotic morbidity and the AngioJet thrombectomy is a new therapy that can be selected for the treatment of LEDVT. We performed a systematic review and meta-analysis of clinical trials comparing AngioJet versus CDT to assess the efficacy and safety of AngioJet thrombectomy. We systematically searched PubMed and Embase for clinical trials that published before November 1, 2020 and compared AngioJet thrombectomy and CDT in the treatment of LEDVT. We meta-analyzed effective rate of treatment, serious complications, PTS, Villalta score, duration of treatment and drug dose. AngioJet does not result in a significant difference in the effective rate (OR 1.00, CI 0.73-1.36, P = 0.98; I² = 0%) and complications (OR 1.16 CI 0.84-1.61, P = 0.36; I² = 39%) compare to CDT. And there was a statistically significant decrease in incidence of PTS (OR 0.58 CI 0.37-0.91, P = 0.02; I² = 0%) and Villalta score (OR −1.86 CI −3.49 to −0.24, P = 0.02; I² = 34%) for AngioJet compared to CDT. In addition, there was a statistically significant decrease in duration of the treatment (OR −2.45 CI −2.75 to −2.15, P < 0.0001; I² = 95%) and drug dose (OR −3.15 CI −3.38 to −2.93, P < 0.0001; I² = 98%) between AngioJet and CDT. AngioJet results in a low severity of PTS compared to CDT therapy. Moreover, the average duration of treatment and thrombolysis time was shorter in the AngioJet group compared to the CDT group. However, the AngioJet group was not significantly different in effective rate of treatment and serious complications compared to the CDT group.

A Case Series of Catheter-Directed Thrombolysis With Mechanical Thrombectomy for Treating Severe Deep Vein Thrombosis

Two cases of extensive symptomatic deep vein thrombosis without phlegmasia cerulea dolens were successfully treated with an endovascular technique that combines catheter-directed thrombolysis and mechanical thrombectomy.

Medicine and Phlebolymphology: Time to Change?

Biomedical science is undergoing a reappraisal of its scientific advancement process and of the related healthcare management. Progress in medicine should combine improvements of knowledge, efficacy, and safety of diagnostic/therapeutic procedures, with adequate cost-effectiveness profiles. This narrative review is aimed at assessing in medicine, more specifically in phlebology and lymphology: (a) scientific literature possible biases, (b) the level of evidence, comprehensiveness, and cost-effectiveness of the main therapeutic options, and (c) the possible contribution of integrative and translational medicine. Current medical research may have cognitive biases, or industry-tied influences, which impacts clinical practice. Some reductionism, with an increasing use of drugs and technology, often neglecting the understanding and care of the root causative pathways of the diseases, is affecting biomedical science as well. Aging brings a relevant burden of chronic degenerative diseases and disabilities, with relevant socio-economic repercussions; thus, a major attention to cost-effectiveness and appropriateness of healthcare is warranted. In this scenario, costly and innovative but relatively validated therapies may tend to be adopted in venous and lymphatic diseases, such as varicose veins, leg venous ulcer, post-thrombotic syndrome, pelvic congestion syndrome, and lymphedema. Conversely, a more comprehensive approach to the basic pathophysiology of chronic venous and lymphatic insufficiency and the inclusion of pharmacoeconomics analyses would benefit overall patients’ management. Erroneous lifestyle and nutrition, together with chronic stress-induced syndromes, significantly influence chronic degenerative phlebo-lymphatic diseases. The main active epigenetic socio-biologic factors are obesity, dysfunctions of musculo-respiratory-vascular pumps, pro-inflammatory nutrition, hyperactivation of stress axis, and sedentarism. An overall critical view of the scientific evidence and innovations in phebolymphology could be of help to improve efficacy, safety, and sustainability of current practice. Translational and integrative medicine may contribute to a patient-centered approach. Conversely, reductionism, eminence/reimbursement-based decisional processes, patients’ lack of education, industry-influenced science, and physician’s improvable awareness, may compromise efficacy, safety, appropriateness, and cost-effectiveness of future diagnostic and therapeutic patterns of phlebology and lymphology.

American Society of Hematology 2020 guidelines for management of venous thromboembolism: treatment of deep vein thrombosis and pulmonary embolism

BACKGROUND

Venous thromboembolism (VTE), which includes deep vein thrombosis (DVT) and pulmonary embolism (PE), occurs in ∼1 to 2 individuals per 1000 each year, corresponding to ∼300 000 to 600 000 events in the United States annually.

OBJECTIVE

These evidence-based guidelines from the American Society of Hematology (ASH) intend to support patients, clinicians, and others in decisions about treatment of VTE.

METHODS

ASH formed a multidisciplinary guideline panel balanced to minimize potential bias from conflicts of interest. The McMaster University GRADE Centre supported the guideline development process, including updating or performing systematic evidence reviews. The panel prioritized clinical questions and outcomes according to their importance for clinicians and adult patients. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to assess evidence and make recommendations, which were subject to public comment.

RESULTS

The panel agreed on 28 recommendations for the initial management of VTE, primary treatment, secondary prevention, and treatment of recurrent VTE events.

CONCLUSIONS

Strong recommendations include the use of thrombolytic therapy for patients with PE and hemodynamic compromise, use of an international normalized ratio (INR) range of 2.0 to 3.0 over a lower INR range for patients with VTE who use a vitamin K antagonist (VKA) for secondary prevention, and use of indefinite anticoagulation for patients with recurrent unprovoked VTE. Conditional recommendations include the preference for home treatment over hospital-based treatment for uncomplicated DVT and PE at low risk for complications and a preference for direct oral anticoagulants over VKA for primary treatment of VTE.

Catheter Interventions for Acute Deep Venous Thrombosis: Who, When and How

Deep venous thrombosis (DVT) is common and can be a source of morbidity by way of pulmonary embolism and post-thrombotic syndrome. Recent trials have demonstrated both early and late symptomatic benefit in venous thrombolysis and early recanalisation of the iliocaval system of selected patients. Based on the emerging evidence, national societies have published guidelines that recommend early thrombus removal in iliofemoral DVT in patients with low bleeding risk and good life expectancy. In light of these recommendations, endovenous thrombolysis and/or thrombectomy have become more popular among vein specialists. As more venous technology becomes available, surgeons and interventionalists should take pause and ensure their patient selection and treatment algorithms parallel that of existing and emerging evidence. This article summarises current evidence, technology, and the approach used at a high-volume academic centre in treating iliofemoral DVT.

Catheter-directed thrombolysis of deep vein thrombosis: literature review and practice considerations

Deep vein thrombosis (DVT) is a major health problem worldwide. The risk of pulmonary embolism following DVT is well established, but the long-term vascular sequelae of DVT are often underappreciated, costly to manage, and can have extremely detrimental effects on quality of life. Treatment of DVT classically involves oral anticoagulation, which reduces the risk of pulmonary embolism but does not remove the clot. Anticoagulation therefore does little to prevent the venous damage and scarring that occurs following DVT, leaving the patient at risk for permanent venous insufficiency and development of post-thrombotic syndrome (PTS). Catheter-directed thrombolysis (CDT) is a minimally invasive endovascular treatment that is used as an adjunct to anticoagulation. CDT lowers the risk of PTS by reducing clot burden and protecting against valvular damage. A catheter is advanced directly to the site of thrombosis under fluoroscopy followed by a slow, prolonged infusion of a relatively low dose of thrombolytic agent. CDT restores venous patency faster than anticoagulation, which hastens the relief of acute symptoms. Adjunctive CDT modalities have become increasingly popular among interventional radiologists, allowing for additional mechanical thrombectomy or ultrasound-enhanced thrombolysis at the time of catheter placement. These pharmacomechanical CDT (PCDT) techniques have the potential to reduce treatment time and associated healthcare costs. Numerous observational and retrospective studies have consistently shown a benefit of CDT plus anticoagulation over anticoagulation alone for prevention of PTS. Patients with long life expectancy and acute thrombosis involving the iliac and proximal femoral veins (iliofemoral DVT) have the greatest benefit from CDT, which may decrease the risk of PTS and/or decrease the severity of PTS symptoms if they do occur. Randomized controlled trials remain limited but generally support the observational data. CDT also plays an important role in those with acute limb-threatening venous occlusion or severe symptoms from DVT. Although adverse outcomes are rare, a potential devastating outcome is intracranial bleeding. While the available literature suggests the risk of serious morbidity from bleeding is quite rare, the absolute risk of bleeding is not clear and will require outcomes data from randomized trials. Future studies should also examine the cost-effectiveness of CDT for PTS prevention, particularly with respect to quality-adjusted life years, and compare the effectiveness of available PCDT devices.

Pediatric Thrombolysis: A Practical Approach

The incidence of pediatric venous thromboembolic disease is increasing in hospitalized children. While the mainstay of treatment of pediatric thrombosis is anticoagulation, reports on the use of systemic thrombolysis, endovascular thrombolysis, and mechanical thrombectomy have steadily been increasing in this population. Thrombolysis is indicated in the setting of life- or limb-threatening thrombosis. Thrombolysis can rapidly improve venous patency thereby quickly ameliorating acute signs and symptoms of thrombosis and may improve long-term outcomes such as postthrombotic syndrome. Systemic and endovascular thrombolysis can result in an increase in minor bleeding in pediatric patients, compared with anticoagulation alone, and major bleeding events are a continued concern. Also, endovascular treatment is invasive and requires technical expertise by interventional radiology or vascular surgery, and such expertise may be lacking at many pediatric centers. The goal of this mini-review is to summarize the current state of knowledge of thrombolysis/thrombectomy techniques, benefits, and challenges in pediatric thrombosis.

Pharmacomechanical thrombectomy for iliofemoral deep vein thrombosis

BACKGROUND

Deep venous thrombosis (DVT) occurs in approximately one in 1000 adults every year, and has an annual mortality of 14.6%. In particular, iliofemoral DVT can lead to recurrent thrombosis and post-thrombotic syndrome (PTS), a painful condition which can lead to chronic venous insufficiency, oedema, and ulceration. It causes significant disability, impaired quality of life, and economic burden. Early thrombus removal techniques have been advocated in patients with an iliofemoral DVT in order to improve vein patency, prevent valvular dysfunction, and reduce future complications, such as post-thrombotic syndrome and venous ulceration. One such technique is pharmacomechanical thrombectomy, a combination of catheter-based thrombectomy and catheter-directed thrombolysis.

OBJECTIVES

To assess the effects of pharmacomechanical thrombectomy versus anticoagulation (alone or with compression stockings), mechanical thrombectomy, thrombolysis, or other endovascular techniques in the management of people with acute DVT of the iliofemoral vein.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Specialised Register (last searched December 2015) and the Cochrane Register of Studies (last searched December 2015). We searched clinical trials databases for details of ongoing or unpublished studies and the reference lists of relevant articles retrieved by electronic searches for additional citations.

SELECTION CRITERIA

Randomised controlled trials in which patients with an iliofemoral deep vein thrombosis were allocated to receive pharmacomechanical thrombectomy versus anticoagulation, mechanical thrombectomy, thrombolysis (systemic or catheter directed thrombolysis), or other endovascular techniques for the treatment of iliofemoral DVT.

DATA COLLECTION AND ANALYSIS

At least two review authors independently assessed studies identified for potential inclusion.

MAIN RESULTS

We found no randomised controlled trials that met the eligibility criteria for this review. We identified one ongoing study.

AUTHORS' CONCLUSIONS

There were no randomised controlled trials that assessed the effects of pharmacomechanical thrombectomy versus anticoagulation (alone or with compression stockings), mechanical thrombectomy, thrombolysis, or other endovascular techniques in the management of people with acute DVT of the iliofemoral vein that met the eligibility criteria for this review. Further high quality randomised controlled trials are needed.