Advances in the diagnosis and management of postthrombotic syndrome

Biomarkers and the post-thrombotic syndrome: A systematic review of biomarkers associated with the occurrence of the post-thrombotic syndrome after lower extremity deep venous thrombosis

INTRODUCTION

Post-thrombotic syndrome (PTS) is a frequent chronic complication of deep venous thrombosis (DVT). Biomarkers are potentially valuable clinical tools for handling PTS. The purpose of this review was to examine which biomarkers are associated with the development of PTS in adults with lower extremity DVT.

METHODS

We performed a systematic review of all English language prospective studies of biomarkers and PTS published in PubMed and EMBASE. Studies were included if diagnosing DVT by diagnostic imaging and assessing PTS by clinical scales, for example, the Villalta scale. Biomarkers of thrombophilia and pathological clot properties were not assessed. Data was reported qualitatively.

RESULTS

15 prospective studies were included. Studies varied widely in study design and methods of data analysis. Forty-six different biomarkers were examined, with seven being measured in two or more studies. The most frequently studied biomarkers were D-dimer, CRP, and IL-6. Associations between PTS and D-dimer were predominantly significant, while results on CRP and IL-6 were inconsistent. ICAM-1 was consistently associated with PTS in all studies and at all timepoints. IL-10 was significantly related to PTS development in the largest study and at all time points. Adiponectin, tPA, HRG and TAFI, MMP-1 and -8, and TIMP-1 and -2 were significantly associated with PTS in single studies.

CONCLUSION

(1) Further research on biomarkers and PTS is clearly warranted. (2) Significant differences in study designs made it difficult to draw reliable conclusions regarding individual biomarkers. We suggest the implementation of a standardized framework for the study of biomarkers and PTS, to make comparison of future studies more feasible. (3) D-dimer, ICAM-1, IL-10, MMP-1 and 8, TIMP-1, TIMP-2, and adiponectin are clinical biomarkers of particular interest to include in future studies of PTS. Large scale systemic quantitative proteomic analyses of DVT patients could help identify novel biomarkers of interest in PTS-patients.

Percutaneous mechanical thrombectomy to remove post-thrombotic obstructions and manage post-thrombotic syndrome-associated venous leg ulceration

BACKGROUND

Up to one half of patients with a diagnosis of deep vein thrombosis will develop post-thrombotic syndrome (PTS). Patients with PTS can develop venous leg ulcers (VLUs) due to post-thrombotic obstructions (PTOs) that contribute to prolonged ambulatory venous hypertension. The current treatments for PTS, which include chronic thrombus, synechiae, trabeculations, and inflow lesions, do not target PTOs, and such obstructions can affect stenting success. The aim of the present study was to determine whether removal of chronic PTOs using percutaneous mechanical thrombectomy would promote VLU resolution and positive outcomes.

METHODS

In this retrospective analysis, the characteristics and outcomes for patients with VLUs secondary to chronic PTO who were treated using the ClotTriever System (Inari Medical) between August 2021 and May 2022 were assessed. Technical success was considered the ability to cross a lesion and introduce the thrombectomy device. Clinical success was defined as a decrease of ≥1 in the severity category for the ulcer diameter using the revised venous clinical severity score (score 0, no VLU; score 1, mild VLU [size <2 cm]; score 2, moderate VLU [size 2-6 cm]; score 3, severe VLU [size >6 cm]) at the latest follow-up visit.

RESULTS

A total of 11 patients with 15 VLUs on 14 limbs were identified. Their mean age was 59.7 ± 11.8 years, and four patients (36.4%) were women. The median VLU duration was 11.0 months (interquartile range [IQR], 6.0-17.0 months), and 2 patients had VLUs secondary to a deep vein thrombosis event >40 years previously. All treatments were performed in a single session, with technical success achieved in 100% of the 14 limbs. A median of five passes (IQR, four to six passes) with the ClotTriever catheter were performed per limb. Chronic PTOs were successfully extirpated, and intraprocedural intravascular ultrasound showed effective disruption of venous synechiae and trabeculations. Stents were placed in 10 limbs (71.4%). The time to VLU resolution or the latest follow-up was 12.8 ± 10.5 weeks, and clinical success was achieved for all 15 VLUs (100%), with the revised venous clinical severity score for the ulcer diameter improving from a median of 2 (IQR, 2-2) at baseline to a median score of 0 (IQR, 0-0) at last follow-up. The VLU area had decreased by 96.6% ± 8.7%. Of the 15 VLUs, 12 (80.0%) had resolved completely, and 3 had demonstrated near-complete healing.

CONCLUSIONS

All patients showed complete or near-complete VLU healing within a few months after mechanical thrombectomy. Mechanical extirpation and interruption of chronic PTOs allowed for luminal gain and restoration of cephalad inflow. With additional investigation, mechanical thrombectomy with the study device could prove a vital component to the treatment of VLUs secondary to PTOs.

Chronic venous ulcer resolution and post-thrombotic syndrome improvement after percutaneous mechanical thrombectomy of a 42-year-old deep vein thrombosis

Post-thrombotic syndrome (PTS) is a chronic disease affecting up to one half of patients with deep vein thrombosis. PTS symptoms range in severity, with the worst form involving the development of venous ulcers. In the present report, we have described a patient with PTS with ulceration for >40 years. A percutaneous approach with a mechanical thrombectomy extirpation device was used to remove the chronic thrombus in a single session. At >3 months of follow-up, the PTS symptoms had improved dramatically, and the ulcer had completely healed. We have demonstrated successful removal of long-standing chronic thrombus using the ClotTriever system (Inari Medical, Irvine, CA) and the management of venous ulcers resulting from debilitating PTS.

The Post-thrombotic Syndrome-Prevention and Treatment: VAS-European Independent Foundation in Angiology/Vascular Medicine Position Paper

Importance

The post-thrombotic syndrome (PTS) is the most common long-term complication of deep vein thrombosis (DVT), occurring in up to 40–50% of cases. There are limited evidence-based approaches for PTS clinical management.

Objective

To provide an expert consensus for PTS diagnosis, prevention, and treatment.

Evidence-Review

MEDLINE, Cochrane Database review, and GOOGLE SCHOLAR were searched with the terms “post-thrombotic syndrome” and “post-phlebitic syndrome” used in titles and abstracts up to September 2020.

Filters Were

English, Controlled Clinical Trial / Systematic Review / Meta-Analysis / Guideline. The relevant literature regarding PTS diagnosis, prevention and treatment was reviewed and summarized by the evidence synthesis team. On the basis of this review, a panel of 15 practicing angiology/vascular medicine specialists assessed the appropriateness of several items regarding PTS management on a Likert-9 point scale, according to the RAND/UCLA method, with a two-round modified Delphi method.

Findings

The panelists rated the following as appropriate for diagnosis: 1-the Villalta scale; 2- pre-existing venous insufficiency evaluation; 3-assessment 3–6 months after diagnosis of iliofemoral or femoro-popliteal DVT, and afterwards periodically, according to a personalized schedule depending on the presence or absence of clinically relevant PTS. The items rated as appropriate for symptom relief and prevention were: 1- graduated compression stockings (GCS) or elastic bandages for symptomatic relief in acute DVT, either iliofemoral, popliteal or calf; 2-thigh-length GCS (30–40 mmHg at the ankle) after ilio-femoral DVT; 3- knee-length GCS (30–40 mmHg at the ankle) after popliteal DVT; 4-GCS for different length of times according to the severity of periodically assessed PTS; 5-catheter-directed thrombolysis, with or without mechanical thrombectomy, in patients with iliofemoral obstruction, severe symptoms, and low risk of bleeding. The items rated as appropriate for treatment were: 1- thigh-length GCS (30–40 mmHg at the ankle) after iliofemoral DVT; 2-compression therapy for ulcer treatment; 3- exercise training. The role of endovascular treatment (angioplasty and/or stenting) was rated as uncertain, but it could be considered for severe PTS only in case of stenosis or occlusion above the inguinal ligament, followed by oral anticoagulation.

Conclusions and Relevance

This position paper can help practicing clinicians in PTS management.

Measurement of transcutaneous oxygen pressure in patients with post-thrombotic syndrome: Findings and possible clinical applications

Objectives

Post-thrombotic syndrome is the commonest long-term sequela of deep venous thrombosis. Severe post-thrombotic syndrome reduces importantly the quality of life of patients and tissue hypoxia is associated with ulceration. Transcutaneous oxygen pressure (tcPO2) provides information on the delivery of oxygen through the microvascular circulation and measuring tcPO2 might detect values at which patients with post-thrombotic syndrome might ulcerate. The aim of our study is to determine tcPO2 in post-thrombotic syndrome patients and compare the values with a control group.

Methods

A cross-sectional study was performed. Periflux 5000 monitor (Perimed) was used to measure tcPO2 in patients with mild-moderate, severe post-thrombotic syndrome and control groups. In patients with ulceration, two measurements were obtained, the first around the ulcer and the second 10 cm away from the lesion. Categorical data were analyzed with Fisher’s exact test and a p value <0.05 was considered statistically significant.

Results

Twelve patients with post-thrombotic syndrome and 13 patients (control group) were enrolled. Post-thrombotic syndrome patients’ mean age was 58 years (47–72 years) and eight (67%) patients were males. The overall mean tcPO2 measurement in post-thrombotic syndrome group was 35.5 mm Hg (SD ± 11), while in the severe post-thrombotic syndrome was 23.2 mm Hg (SD ± 9). All severe post-thrombotic syndrome patients had measurements <40 mm Hg, tcPO2 value in control group was >50 mm Hg (SD ± 4) in all patients, with a mean value of 58.2 mm Hg. During comparison of severe post-thrombotic syndrome subgroup versus control group, we found that patients with venous ulcers had <40 mm Hg in tcPO2 measurement and all control group patients had >50 mm Hg ( p < 0.0001).

Conclusions

Our results demonstrate that severe post-thrombotic syndrome patients have significantly lower TcPO2 values compared to a healthy control group and non-severe post-thrombotic syndrome ( p = 0.0001). Further research is necessary to establish cut-off point values of tcPO2 in this debilitating disease for possible clinical applications and determination of ulcer healing predictors.

ANMCO Position Paper: long-term follow-up of patients with pulmonary thromboembolism

Venous thromboembolism (VTE), including pulmonary embolism and deep venous thrombosis, is the third most common cause of cardiovascular death. The management of the acute phase of VTE has already been described in several guidelines. However, the management of the follow-up (FU) of these patients has been poorly defined. This consensus document, created by the Italian cardiologists, wants to clarify this issue using the currently available evidence in VTE. Clinical and instrumental data acquired during the acute phase of the disease are the cornerstone for planning the FU. Acquired or congenital thrombophilic disorders could be identified in apparently unprovoked VTE during the FU. In other cases, an occult cancer could be discovered after a VTE. The main targets of the post-acute management are to prevent recurrence of VTE and to identify the patients who can develop a chronic thromboembolic pulmonary hypertension. Knowledge of pathophysiology and therapeutic approaches is fundamental to decide the most appropriate long-term treatment. Moreover, prognostic stratification during the FU should be constantly updated on the basis of the new evidence acquired. Currently, the cornerstone of VTE treatment is represented by both the oral and the parenteral anticoagulation. Novel oral anticoagulants should be an interesting alternative in the long-term treatment.

Ischemic Stroke and Risk of Venous Thromboembolism in the General Population: The Tromsø Study

Background

Even though clinical data support a relation between ischemic stroke and venous thromboembolism (VTE), the strength and time dependence of the association remain to be settled at the population level. We therefore aimed to investigate the association between ischemic stroke and VTE in a prospective population‐based cohort.

Methods and Results

Participants (n=30 002) were recruited from 3 surveys of the Tromsø study (conducted in 1994–1995, 2001, and 2007–2008) and followed through 2010. All incident events of ischemic stroke and VTE during follow‐up were recorded. Cox‐regression models with age as time scale and ischemic stroke as a time‐dependent variable were used to calculate hazard ratios (HR) of VTE adjusted for cardiovascular risk factors. During a median follow‐up time of 15.7 years, 1360 participants developed ischemic stroke and 722 had a VTE. The risk of VTE was highest the first month (HR 19.7; 95% CI, 10.1–38.5) and from 1 to 3 months after the stroke (HR 10.6; 95% CI 5.0–22.5), but declined rapidly thereafter. The risk estimates were approximately the same for deep vein thrombosis (HR 19.1; 95% CI, 7.8–38.5), and pulmonary embolism (HR 20.2; 95% CI, 7.4–55.1). Stroke was associated with higher risk for provoked (HR 22.6; 95% CI, 12.5–40.9) than unprovoked VTE (HR 7.4; 95% CI, 2.7–20.1) the first 3 months.

Conclusions

The risk of VTE increased during the first 3 months after an ischemic stroke. The particularly high risk of provoked VTE suggests that additional predisposing factors, such as immobilization, potentiate the VTE risk in patients with ischemic stroke.

Rates of elastic compression stockings prescription following the diagnosis of deep venous thrombosis among Canadian emergency physicians and trainees

Introduction Postthrombotic syndrome (PTS) is a complication of deep vein thrombosis (DVT) characterized by chronic pain, swelling, and heaviness, and may result in ulceration. Elastic compression stockings (ECS) worn daily after DVT have been shown to reduce the incidence and severity of PTS. The aim of our study was to investigate practices and perceptions of physicians regarding adjunct therapies to anticoagulation in patients diagnosed with lower extremity DVT.

METHODS

A national online survey was conducted of Canadian emergency medicine staff physicians and residents (n=471) to investigate their attitudes toward the prescription of ECS post-diagnosis of DVT. A paper survey of patients in a thrombosis clinic (n=58) was also administered to better understand the patient experiences with ECS.

RESULTS

The majority of staff physician (62%) and resident (69%) respondents were unsure of whether ECS were effective in preventing PTS and managing venous symptoms. Only 6% of staff physicians and 7% of residents routinely prescribed ECS for above-knee DVTs. More than 78% of respondents were unsure about the optimal timing of initiation of ECS and duration of therapy. Although all patients noted symptomatic relief with ECS, only 50% were prescribed stockings by an emergency or family doctor, and 69% of those patients wore the stockings on a daily basis. Staff physicians most frequently identified poor fit as the reason for lack of patient compliance, whereas patients most frequently cited cost.

CONCLUSIONS

Our findings suggest that there is variability in practice among Canadian emergency medicine physicians and trainees and a need for widespread education regarding the latest evidence of the benefit of ECS after DVT.