The background and role of catheter-directed thrombolysis evolving procedures for acute iliofemoral deep venous thrombosis

Minimal invasive treatment such as early endovenous thrombus removal for iliofemoral deep venous thrombosis (DVT) emerged in the end of last century. The principle is catheter-directed thrombolysis (CDT) using either plasminogen activating agents alone, as ultrasound-assisted CDT, or in combination with mechanical devices as pharmaco-mechanical CDT. The interest for this treatment modality is the high rate of post-thrombotic syndrome (PTS) with anticoagulation (AC) alone, especially after iliofemoral DVT. Recently published randomized controlled trials (RCTs) comparing early thrombus removal with AC alone, as well as non-randomized studies, have demonstrated favorable rates, or at least a decrease of moderate and severe PTS, in favor of these procedures. This article will summarize the background and evolution of the procedures in the last three decades and discuss fundamental criteria for inclusion and exclusion, focusing on the procedures regarding thrombus age and location, technical issues, complications and results including different outcome measures for PTS, for which iliac DVT involvement is a massive risk factor to be prevented.

Safety and Efficacy of Catheter Direct Thrombolysis in Management of Acute Iliofemoral Deep Vein Thrombosis: A Systematic Review

Purpose

Catheter direct thrombolysis (CDT) has been shown to be an effective treatment for deep venous thrombosis. The objective of the review is to improve safety and efficacy of the CDT by using ward based protocol, better able to predict complications and treatment outcome through monitoring of haemostatic parameters and clinical observation during thrombolysis procedure.

Materials and Methods

MEDLINE, EMBASE, CENTRAL and Web of Science were searched for all articles on deep venous thrombosis, thrombolysis and correlations of clinical events (bleeding, successful thrombolysis) during thrombolysis with hemostatic parameters to March 2016. The risk of bias in included studies was assessed by Cochrane Collaboration’s tool and Cochrane Risk of Bias Assessment Tool: for Non-Randomized Studies of Interventions.

Results

Twenty-four studies were included in the review and we found that improving safety and efficacy of CDT by using ward based protocol depending on eight factors; strict patient selection criteria, types of fibrinolytic drugs, mode of fibrinolytic drug injection, biochemical markers monitoring (fibrinogen, D-dimer, activated partial thromboplastin time, plasminogen activator inhibitor-1), timing of intervention, usage of intermittent pneumatic calf, ward monitoring and thrombolysis imaging assessment (intravascular ultrasound). These factors may help to improve safety and efficacy by reducing total thrombolytic drug dosage and at the same time ensure successful lysis. There is a marked lack of randomized controlled trials discussing the safety and efficacy of catheter direct thrombolysis.

Conclusion

CDT can be performed safely and efficiently in clinical ward, providing that careful nursing, biochemical monitoring, proper selection and mode of infusion of fibrinolytic drugs, usage of Intermittent pneumatic calf and adequate thrombolysis imaging assessment are ensured.

Feasibility of continuous, catheter-directed thrombolysis using low-dose urokinase in combination with low molecular-weight heparin for acute iliofemoral venous thrombosis in patients at risk of bleeding

The present study aimed to examine the feasibility of catheter-directed thrombolysis (CDT) using continuous infusion of low-dose urokinase in combination with low molecular weight heparin (LMWH) for acute iliofemoral venous thrombosis. This retrospective analysis included patients with symptomatic acute iliofemoral venous thrombosis who received CDT using continuous infusion of low-dose urokinase in combination with LMWH within the past four years. Urokinase was administered at 1×10⁴ U/h and 2×10⁴ U/h in patients at high-risk and low-risk of bleeding, respectively. Measurements included urokinase dosage, duration, clinical outcomes and CDT-related complications. A total of 46 patients were included (high-risk, n=17; low-risk, n=29). In the high-risk patients, 64.7% experienced dissolution of ≥50% thrombi after a median CDT duration of 8 days (range, 6-10 days) and median total urokinase dose of 1.92×10⁶ units (range, 1.44-2.4×10⁶ units). In the low-risk patients, 82.8% achieved dissolution of ≥50% thrombi after a median CDT duration of 7 days (range, 4-10 days) and a median total urokinase dose of 3.36×10⁶ units (range, 1.92-4.80×10⁶ units). Remission of clinical symptoms after CDT was achieved in 15 (88.2%) and 28 (96.6%) cases in high-risk and low-risk patients, respectively. No treatment-associated pulmonary embolism or major bleeding was observed. Three (6.5%) subjects (high-risk, n=1; low-risk, n=2) experienced minor bleeding. In conclusion, continuous infusion of low-dose urokinase via CDT in combination with LMWH is effective and safe for acute iliofemoral venous thrombosis in patients with one or more risk factor for bleeding.

Should catheter-directed thrombolysis be monitored?

Catheter-directed thrombolysis for deep venous thrombosis is considered the basic treatment modality for intrathrombus removal. This method is preferably used in patients with iliofemoral deep venous thrombosis due to poor spontaneous recanalization in this segment, especially on the left side. The method was published almost 25 years ago and has gained ground in the treatment because of poor results from systemic thrombolysis and because of the possibility of stenting any underlying iliac obstruction during the procedure. However, the publications of catheter-directed thrombolysis reveal a great heterogeneity concerning catheter-directed thrombolysis technique and the lack of high quality evidence about monitoring as a tool to minimize the risk of bleeding and pulmonary embolism. Strict inclusion and exclusion criteria, correct composition and infusion of thrombolysis agent, imaging thrombus clearance during catheter-directed thrombolysis, ensuring flow enhancement during the bedridden situation, careful evaluation of indication for stenting based on imaging, and sufficient conversion to anticoagulation treatment following catheter-directed thrombolysis are essential. The aim of this paper is to discuss different treatment aspects of catheter-directed thrombolysis for iliofemoral thrombosis and to suggest a monitoring model for future treatment.

Safety of Intra-arterial Catheter Directed Thrombolysis: Does Level of Care Matter?

OBJECTIVES

The aim was to assess whether the level of care influenced the safety related outcomes of catheter directed thrombolysis (CDT) for patients presenting with limb ischaemia and dialysis access thrombosis.

METHODS

This was a retrospective cohort study. All consecutive patients at two tertiary referral centres for vascular surgery undergoing CDT for limb ischaemia and dialysis access thrombosis (N = 252) between 2012 and 2014 were included. Patients at Centre 1 were cared for on a general vascular ward and patients at Centre 2 were kept on a post-operative recovery unit with an increased level of care including invasive haemodynamic monitoring. Patient medical records were retrospectively scrutinised and data collected on comorbidities, anti-thrombotic medication, indications for CDT, technical success of CDT, bleeding and non-bleeding related complications, and transfer to a higher level of care.

RESULTS

There were no differences in the frequency of non-bleeding related complications between Centre 1 and Centre 2. Patients on the vascular ward had a higher frequency of minor bleeding (p = .002) but there was no difference in major bleeding (p = .12). Eleven patients on the ward required an increased level of care for medical reasons and six were moved for a lack of resources. The presence of cardiac disease was an independent risk factor for patient transfer (OR 3.2; 95% CI 1.04-9.8, p = .04).

CONCLUSIONS

CDT may be undertaken outside of a high dependency setting without a significantly increased risk of complications. Pre-existing cardiac disease was an independent risk factor for transfer to a higher level of care. These findings could have an implication for the clinical cost-effectiveness of CDT.

Contemporary management of acute and chronic deep venous thrombosis

INTRODUCTION

This review aims to provide an update on the management of deep vein thrombosis (DVT).

SOURCES OF DATA

A systematic search of PubMed, Google Scholar and Cochrane databases was carried out.

AREAS OF AGREEMENT

Direct oral anticoagulants (DOACs) are as effective and easier to use than vitamin K antagonists for the treatment of DVT. Catheter-directed thrombolysis can reduce post thrombotic syndrome in patients with iliofemoral DVT. Compression bandaging can help heal a venous ulcer.

AREAS OF CONTROVERSY

Compression hosiery to prevent post thrombotic syndrome. Long-term evidence to show clinical benefit of using endovenous therapies to restore deep vein patency.

GROWING POINTS

Developing imaging methods to identify patients who would benefit from venous thrombolysis. The evolution of dedicated venous stents.

AREAS TIMELY FOR DEVELOPING RESEARCH

Understanding the mechanisms that lead to stent occlusion and investigation into the appropriate treatments that could prevent in-stent thrombosis is required.

Efficacy of Retrievable Inferior Vena Cava Filter Placement in the Prevention of Pulmonary Embolism during Catheter-Directed Thrombectomy for Proximal Lower-Extremity Deep Vein Thrombosis

BACKGROUND

Inferior vena cava (IVC) filter placement is not indicated for thrombolytic interventional treatment for deep vein thrombosis (DVT). We analyzed the efficacy and feasibility of retrievable IVC filter placement for the preventive management of embolic shedding during catheter-directed thrombectomy (CDT) for DVT of lower extremity.

METHODS

Seventy patients (35 males and 35 females) who underwent retrievable IVC filter placement to prevent thrombus dislodgement during CDT in all symptomatic DVT with thrombus age suspected within 4 weeks of the lower extremity between March 2008 and January 2014 were included in this study. All patients underwent laboratory blood study, duplex ultrasound and/or computed tomography for diagnosis, treatment, and follow-up in accordance with treatment policy of our Uijeongbu St. Mary's hospital. Two types of retrievable IVC filters (OptEase Filter, Cordis, Roden, The Netherlands; Gunther Tulip Filter, Cook, Bloomington, IN) were used to prevent thromboembolic events during CDT. After filter placement, subcutaneous low-molecular-weight heparin and overlapped to warfarin or new oral anticoagulant tried to achieve a target international normalized ratio (INR) of 2.0-3.0 in warfarin patients.

RESULTS

The thrombus was dislodged through the IVC filter during catheter-directed thrombolytic therapy in 22 patients (31.4%). In 22 cases, the thromboses were trapped by the retrievable IVC filter, and follow-up images showed thrombus capture. Thirty-four patients (48.6%) received percutaneous transluminal angioplasty (PTA). Additional stents were inserted in 23 patients (32.8%). Pulmonary embolism (PE) was not observed in patients implanted with retrievable IVC filters.

CONCLUSIONS

Our study findings suggest that retrieval IVC filter placement during interventional treatments of DVT of lower extremity such as thrombectomy of vein thrombus with or without stent insertion at compressed deep vein is favorable and effective for protecting against PE or lethal complications. We recommend carefully that before the management of DVT thrombus of lower extremity, retrieval IVC filter placement should be considered for preventing morbidity related with the PE.

Gadofosveset-enhanced magnetic resonance venography in patients with venous pathology of the lower limbs - Comparison of diagnostic image quality and inter-rater variability with gadobutrol venography and computed tomography venography

Purpose This study was performed to compare the diagnostic quality of Gadofosveset-enhanced magnetic resonance venography with Gadobutrol-enhanced magnetic resonance venography and computed tomography venography for the deep veins of the lower extremities in patients with iliocaval venous pathology. Materials and methods Diagnostic capability and image quality were assessed by two independent readers. Inter-reader variability was analyzed by unweighted and quadratic weighted Cohen's kappa values. Results The diagnostic capability was equal to or higher in the Gadofosveset group for all examined vessel segments compared with both control groups. The image quality score was significantly higher for the Gadofosveset group compared to both control groups. Inter-reader variability expressed by quadratic weighted Cohen's kappa value (k) showed less variability in the Gadofosveset group compared to the control groups. Conclusion Our results show that Gadofosveset-enhanced magnetic resonance venography is a reliable technique in clinical routine practice, with image quality superior to both Gadobutrol-enhanced magnetic resonance venography and computed tomography venography.

Percutaneous manual aspiration thrombectomy followed by stenting for iliac vein compression syndrome with secondary acute isolated iliofemoral deep vein thrombosis: a prospective study of single-session endovascular protocol

OBJECTIVE

To evaluate the feasibility, safety, and effectiveness of single-session endovascular treatment with manual aspiration thrombectomy (MAT) as the first-line method of thrombus removal for iliac vein compression syndrome (IVCS) with secondary acute isolated iliofemoral deep vein thrombosis (DVT).

METHODS

This was a prospective clinical study. Twenty-six patients (19 women, 7 men, mean age 54 years) with left-sided acute iliac-common femoral DVT secondary to IVCS were enrolled. All patients presented with leg swelling or pains. Endovascular treatment, consisting of MAT, balloon angioplasty, and stent placement, was performed in the same setting. Overnight antegrade thrombolysis was performed in patients with residual thrombus after MAT. Patients were followed up by ultrasonography. The mean follow-up period was 17.8 months (12-25 months).

RESULTS

Single-session endovascular procedures were performed successfully in all patients. The mean procedure time was 67 minutes (ranging from 45 to 90 minutes). Complete thrombus removal, including almost 100% of removal in 24 patients and little residual thrombus (<5%) in two, was achieved after repeated MAT. Thrombolysis was used in these two patients. Complete symptomatic relief was achieved in 25 patients (96%) and partial relief in one. The hospital stay ranged from 2 to 4 days (mean 2.7 days). Recurrent thrombosis within the stent was observed in one case and recanalized with thrombolysis. The 1-year primary and secondary patency rate was 96% and 100%, respectively. No symptomatic pulmonary embolization, bleeding, and venous reflux were observed. Five patients complained about transitory low back pains during balloon angioplasty.

CONCLUSION

Single-session endovascular treatment with MAT as the first-line thrombus removal method is feasible, safe, and effective for IVCS with secondary acute isolated iliofemoral DVT. Although limited, our experience suggests that patients thought to be at high risk of bleeding may be candidates for the present single-session endovascular protocol.

Early re-presentations and the potential role of catheter-directed thrombolysis in patients diagnosed with a lower limb deep vein thrombosis: a single-centre experience

Introduction

Catheter-directed thrombolysis (CDT) for iliofemoral deep vein thrombosis (DVT) restores venous patency, reduces the risk of the post-thrombotic syndrome and may reduce longer term treatment costs. This study assessed the potential role of CDT in patients with DVT with regard to representation following the index event.

Methods

A retrospective review of all patients with a positive lower limb DVT scan. Potential suitability of each patient to undergo CDT was based on well-recognized inclusion/exclusion criteria.

Results

In total, 1689 patients underwent a DVT-specific lower limb venous duplex. A total of 269 were found to have a DVT. Fifty-three of these patients met the inclusion criteria for CDT (only 2 underwent CDT). Fifty-nine of the 269 patients with an index DVT re-presented to our institution with a venous thromboembolism-related clinical event. These patients were significantly younger than those who did not reattend. A higher proportion of patients who represented were deemed suitable for CDT for the index DVT compared with those who did not represent (17/59 versus 36/210; P = 0.04).

Conclusion

This pragmatic study highlights the fact that significant number of patients return to secondary care with actual/perceived complications following initial diagnosis and treatment of a DVT which may have been amenable to CDT.