Treatment options for venous thromboembolism: lessons learnt from clinical trials

Ischemic stroke subtypes: risk factors, treatments, and 1-month prognosis - The Lille, France Stroke Registry

OBJECTIVES

First, this registry-based study aimed to comprehensively analyze patients' medical histories and treatments based on ischemic strokes' etiology. We focused on the management of atrial fibrillation among patients diagnosed with cardioembolic stroke. Then, our objective was to identify prognostic factors associated with 28-day mortality.

MATERIALS AND METHODS

All ischemic strokes occurring in adults between 2014 and 2021 in Lille, France, were categorized using the TOAST classification. Comparative analyses of patients' medical characteristics were conducted across subtypes. Survival rates within 28 days post-stroke were assessed, and factors influencing mortality were identified using a multivariate Cox model.

RESULTS

1912 ischemic strokes were recorded, due to cardioembolism (36%), large-artery atherosclerosis (9%), small-artery occlusion (9%), other determined causes (6%), or undetermined causes (39%). The median NIHSS score after cardioembolic stroke (6, IQR: 3-13) was twice that after small-artery occlusion (3, IQR: 2-5). Among patients with cardioembolic stroke, 26% were diagnosed post-admission with atrial fibrillation. For the 42% diagnosed pre-admission, only 54% had prior prescriptions for oral anticoagulants. Reperfusion therapies were administered in 21% of cases, with significant variations across subtypes. Mortality rates were higher after cardioembolic strokes (17%) than after small-artery occlusions (3%). Prognostic factors included etiology, high NIHSS score, atrial fibrillation, and previous heparin prescription.

CONCLUSIONS

While atrial fibrillation was underdiagnosed and undertreated, patients with cardioembolic stroke exhibited high severity and elevated mortality rates. Etiology emerged as an independent predictor of early mortality, regardless of NIHSS score upon admission. These findings underscore the importance of targeted prevention to improve patient outcomes after ischemic stroke.

Effect of the timing of iliac vein stent implantation on catheter-directed thrombolysis in acute lower extremity deep venous thrombosis patients with severe iliac vein stenosis: a retrospective study

OBJECTIVE

To investigate the effect of the timing of iliac vein stent implantation on catheter-directed thrombolysis (CDT) in acute lower extremity deep venous thrombosis (DVT) patients with severe iliac vein stenosis.

METHODS

The clinical data of 66 patients with acute lower extremity DVT complicated with severe iliac vein stenosis from May 2017 to May 2020 were retrospectively analyzed. Patients were divided into two groups by timing of iliac vein stent implantation: group A (iliac vein stent implantation before CDT treatment) for 34 and group B (iliac vein stent implantation after CDT treatment) for 32. The detumescence rate of affected limb, the thrombus clearance rate, the thrombolytic efficiency, the complication rate, the hospitalization cost, the stent patency rate within 1 year, and the scores (venous clinical severity score, Villalta, and chronic venous insufficiency questionnaire (CIVIQ) score) at 1 year postoperatively were compared between the two groups.

RESULTS

The thrombolytic efficiency of group A was higher than that of group B, while the incidence of complications and hospitalization expenses in group A were lower than those in group B. There was no statistical significance in the detumescence rate of affected limb, the thrombus clearance rate, the stent patency rate within 1 year, and the scores (VCSS, Villalta, and CIVIQ score) at 1 year postoperatively between the two groups.

CONCLUSIONS

For acute lower extremity DVT patients with severe iliac vein stenosis, iliac vein stent implantation before CDT treatment can improve the thrombolytic efficiency, and reduce the incidence of complications and hospitalization costs.

The Incidence and Characteristics of Venous Thromboembolism in Neurocritical Care Patients: A Prospective Observational Study

Risk of venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE), is presumed to be high for neurologic intensive care unit (NICU) patients. However, exact incidences of VTE have yet to be reported. In this prospective observational study, we consecutively enrolled 126 neurocritical care patients who had an NICU stay ≥1 week with paralysis and/or unconsciousness. All patients received DVT prevention strategies. Patients were screened for VTE after 1 week of hospitalization, using venous ultrasonography and computed tomography pulmonary angiography. Following 1 week of NICU hospitalization, DVT incidence was 35.7% and PE incidence was 17.5%. Of the DVTs, 75.6% were in the muscular calf vein. Of the PEs, 22.7% were in main pulmonary arteries, while 77.3% were in branches. Approximately 96% of the DVTs and 86% of the PEs were asymptomatic. Approximately 24% of patients with DVT had a concurrent PE, while 50% of PE patients had a DVT. Paralysis, raised d-dimer on admission, and pulmonary infection were found to be independent risk factors for DVT. Paraplegia, femoral vein thrombosis, and pulmonary infection were found to be independent risk factors for PE. Despite active preventive measures, incidences of VTE in NICU patients were high. Most VTEs were asymptomatic, meaning they could have led to a missed diagnosis. Attention should be paid to the VTE events of critically ill neurological patients.

Symptomatic Venous Thromboembolism After Adolescent Knee Arthroscopy

BACKGROUND

The frequency of knee arthroscopy procedures is increasing in pediatric and adolescent patients. In general, complications after these procedures in adolescents are uncommon. The purposes of this study are to report the incidence of venous thromboembolism (VTE) in adolescent patients after knee arthroscopy procedures, as well identify risk factors in this patient population.

METHODS

Medical records were reviewed in all pediatric and adolescent patients (≤19 y) who underwent an arthroscopic knee procedure from 2010 to 2014 and were diagnosed with a symptomatic VTE in the postoperative period. Demographic features were recorded, and included age, sex, body mass index, clinical characteristics (diagnosis, type of surgical intervention, tourniquet time), VTE risk factors [family history of VTE, obesity (body mass index >30), oral contraceptive use, and smoking use/exposure] and treatment (anticoagulation type/duration).

RESULTS

Out of 2783 patients who underwent knee arthroscopy during the 5-year study period, 7 patients (3 males, 4 females, mean age, 16.9 y, range, 15 to 18) developed a symptomatic postoperative VTE (incidence, 0.25%, 95% confidence interval, 0.11%-0.54%). There were 6 unilateral deep venous thrombosis, and 1 bilateral deep venous thrombosis. Arthroscopic procedures performed in this cohort included anterior cruciate ligament reconstruction (3), isolated lateral release (1), meniscectomy (2), and patellar realignment with arthroscopic lateral release, open tibial tubercle osteotomy, and open proximal medial retinacular reefing (1). VTE was diagnosed an average of 9 days following surgery (range, 3 to 16). All patients were initially treated with low-molecular-weight heparin, and 2 were converted to warfarin. Mean duration of anticoagulation treatment was 64 days (range, 28 to 183). All patients had at least 1 identifiable medical or surgical risk factor, including oral contraceptive use (2), smoking (2), obesity (2), an arthroscopically assisted open procedure (4), or tourniquet time >60 minutes (3).

CONCLUSIONS

VTE after adolescent knee arthroscopy has not been well described. The incidence is ∼0.25%. Previously established risk factors for VTE were present in 100% of the affected population. Low-molecular-weight heparin was used to successfully treat this complication.

LEVEL OF EVIDENCE

Level IV.

Lesson of the month 2: Pulmonary embolism in a patient on rivaroxaban and concurrent carbamazepine

A 71-year-old female with a history of pulmonary embolism treated with rivaroxaban presented with acute onset shortness of breath, chest pain and palpitations. Computed tomographic pulmonary angiography (CTPA) revealed multiple bilateral pulmonary emboli. The patient was concurrently prescribed carbamazepine and was later diagnosed with recurrence of breast cancer during the admission. We discuss common drug interactions pertinent to direct oral anticoagulants (DOACs) that can increase the risk of further venous thromboembolism. This case report highlights the importance of reviewing patient medications when considering anticoagulants and the need to raise awareness of these drug interactions among clinicians when making their choice of anticoagulation. It also reinforces the current lack of evidence for use of DOACs in patients with solid organ malignancies.

Desmoid Fibromatosis Presenting as Deep Venous Thrombosis: A Case Report and Discussion

Patient: Male, 40

Final Diagnosis: Desmoid fibromatosis

Symptoms: Discomfort

Medication: —

Clinical Procedure: Surgery and radiotherapy

Specialty: Surgery

Prophylaxis of Venous Thrombosis in Neurocritical Care Patients: An Evidence-Based Guideline: A Statement for Healthcare Professionals from the Neurocritical Care Society

The risk of death from venous thromboembolism (VTE) is high in intensive care unit patients with neurological diagnoses. This is due to an increased risk of venous stasis secondary to paralysis as well as an increased prevalence of underlying pathologies that cause endothelial activation and create an increased risk of embolus formation. In many of these diseases, there is an associated risk from bleeding because of standard VTE prophylaxis. There is a paucity of prospective studies examining different VTE prophylaxis strategies in the neurologically ill. The lack of a solid evidentiary base has posed challenges for the establishment of consistent and evidence-based clinical practice standards. In response to this need for guidance, the Neurocritical Care Society set out to develop and evidence-based guideline using GRADE to safely reduce VTE and its associated complications.

Successful use of rivaroxaban in postoperative deep vein thrombosis of the lower limb following instability with warfarin: a case report

Background

Evidence from clinical trials shows rivaroxaban to be effective for the treatment of deep vein thrombosis. Switching to rivaroxaban following failure of indirect anticoagulants in deep vein thrombosis has not been demonstrated in a real-life setting.

Case presentation

A 43-year-old white woman was switched from warfarin to rivaroxaban for the treatment of thrombosis of her right common femoral vein after saphenectomy. The reason for the switch was due to the instability of anti-coagulation therapy with vitamin K antagonists over a period of 3 months during which she did not reach the “therapeutic range” of prothrombin time-international normalized ratio.

The ineffectiveness of the conventional oral anticoagulant was confirmed by persistence of moderate-high values of fibrin D dimers (780 ng/ml) and by residual vein thrombosis at an ultrasound examination. Objectively, her right leg appeared to be still edematous and warm and pain was elicited by deep palpation. Rivaroxaban was administered after warfarin discontinuation (prothrombin time-international normalized ratio = 1.43) at a dosage of 15 mg every 12 hours for 3 weeks, followed by 20 mg once daily for 3 months. After this period, her objective symptoms significantly improved, with reduction of edema of her lower limb and pain relief. Her fibrin D dimer values returned to normal (210 ng/ml). An ultrasound showed recanalization of the obstructed venous segment.

Conclusions

In this case report, a switch to rivaroxaban from warfarin was shown to be effective and safe for the treatment of postoperative deep vein thrombosis, whereas standard oral anticoagulation therapy, which required dose adjustments over a period of 3 months, was not able to stabilize the therapeutic range of prothrombin time-international normalized ratio nor improve our patient’s outcome.

Edoxaban: A Review in Deep Vein Thrombosis and Pulmonary Embolism

Edoxaban (Lixiana, Savaysa) is an oral, direct factor Xa inhibitor which has recently been approved for use in the treatment of deep vein thrombosis (DVT) and pulmonary embolism (PE) [collectively, venous thromboembolism (VTE)] and for the prevention of recurrent VTE. This article reviews the pharmacological properties of edoxaban as well as its tolerability and therapeutic efficacy in the treatment and prevention of recurrent VTE events. As demonstrated in the pivotal Hokusai-VTE phase III trial, once-daily edoxaban after initial treatment with heparin was non-inferior to standard therapy with heparin/warfarin in preventing recurrent VTE events and was associated with a significantly lower risk of clinically relevant bleeding than the traditional therapy. Edoxaban shares the advantages of other direct oral anticoagulants (DOACs) over traditional therapies, including the lack of requirement for routine coagulation monitoring, a rapid onset and offset of action, and few drug-drug interactions. It offers the convenience of once-daily dosing, can be taken without regard to food and allows for a dose reduction in patients with certain clinical features, such as moderate renal impairment or low body weight. In conclusion, edoxaban represents an effective and potentially safer alternative to traditional vitamin K antagonist therapy for the treatment and prevention of recurrent VTE. Its recent approval expands the range of DOAC agents for recurrent VTE, further facilitating treatment individualization.

In vivo evaluation of a new vena cava filter

Background

Pulmonary embolism is an important cause of cardiovascular death. Inferior vena cava filters have been shown to be effective for prevention of this condition.

Objectives

To determine the safety, performance and efficacy of a new inferior vena cava filter in an ovine model.

Methods

BKone1 filters are self-centering with over-the-wire deployment, have three filtering regions and are made from nickel-titanium alloy. Eight of these filters were implanted in 8 sheep. The sheep were divided into 4 groups of two animals (A and B) and the number of clots injected differed by group. Two clots were injected in group 2, four in group 3, eight in group 4 and zero clots in group 1. A animals underwent euthanasia soon after the procedure and B animals were observed for 30 days and then euthanized after a control cavography. All inferior vena cavas were processed for histological examination. Clots were prepared in a metal mold, sectioned and then radiopaque markers were inserted. Clot capture was analyzed by identifying the radiopaque marker on fluoroscopy.

Results

No clot migration was observed during follow-up. Control cavographies showed patent inferior vena cavas. Pathological examination indicated little inflammatory tissue response. All clots were captured in the condition with 2 clots, only one clot was missed in the group injected with 4 clots and in the condition of 8 clots, they were partly captured.

Conclusions

The filters were deployed safely. There was a reduction in efficacy as the number of blood clots increased.

Heart failure and risk of venous thromboembolism: a systematic review and meta-analysis

BACKGROUND

Venous thromboembolism is a major global health problem that is often secondary to other clinical situations. Many studies have investigated the association between venous thromboembolism and heart failure, but have yielded inconsistent findings. We aimed to quantify the absolute and relative risks (RR) for venous thromboembolism in patients with heart failure after hospital admission. We also assessed rates of venous thromboembolism in patients in different settings.

METHODS

In this systematic review and meta-analysis, we searched for studies investigating the risk of venous thromboembolism in patients in hospital with heart failure. We searched for studies published between Jan 1, 1955, and March 31, 2015, in PubMed, Embase, Evidence-Based Medicine Reviews, Allied and Complementary Medicine Database, Ovid HealthSTAR, Global Health, Ovid Nursing Database, Web of Science, CINAHL Plus, ProQuest Central, Conference Papers Index, BIOSIS Previews, and ClinicalTrials.gov. All cohort studies and subgroup analyses of randomised controlled trials (RCTs) were eligible for inclusion if they reported venous thromboembolism rates (number of events per follow-up period) or RR estimates. We extracted data from published reports and contacted the corresponding authors of records with insufficient quantitative data. RRs and 95% CIs were pooled using a random-effects model. This study is registered with PROSPERO, number CRD42014015504.

FINDINGS

Of 8673 records identified, we included 71 studies with data from 88 cohorts in our analysis, with 59 cohorts included in the assessment of venous thromboembolism rates and 46 cohorts included in the meta-analysis of heart failure and risk of venous thromboembolism. Venous thromboembolism rates varied widely in patients in hospital with heart failure from different settings. The overall median symptomatic venous thromboembolism rate was 2·48% (IQR 0·84-5·61); rates was were 3·73% (1·05-7·31) for patients who did not receive thromboprophylaxis and 1·47% (0·64-3·54) for those who did. Overall, patients with heart failure in hospital had an RR of 1·51 (1·36-1·68) for venous thromboembolism. The overall I(2) statistic was 96·1% and there was no evidence of publication bias (Egger's test, p=0·46).

INTERPRETATION

Heart failure is a common independent risk factor for venous thromboembolism. Thromoboprophylaxis should be considered in clinical practice for high-risk patients.

FUNDING

National Natural Science Foundation.

Cost-effectiveness of edoxaban for the treatment of venous thromboembolism based on the Hokusai-VTE study

OBJECTIVE

Venous thromboembolism (VTE) is associated with almost 300,000 deaths per year in the United States. Novel oral anticoagulants (NOACs) offer an alternative to warfarin-based therapy without monitoring requirements and with fewer drug and food interactions. Edoxaban, a direct Xa inhibitor, is approved by the Food and Drug Administration (FDA), based upon results of the Hokusai-VTE Phase 3 trial. The trial demonstrated that edoxaban administered once daily after initial treatment with heparin was non-inferior in reducing the risk of VTE recurrence and caused significantly less major and clinically relevant non-major (CRNM) bleeding compared to warfarin. The objective of this study was to evaluate the cost-effectiveness of edoxaban versus warfarin for the treatment of adults with VTE.

METHODS

A cost-effectiveness model was developed using patient-level data from the Hokusai-VTE trial, clinical event costs from real-world databases, and drug acquisition costs for warfarin of $0.36 and edoxaban of $9.24 per tablet.

RESULTS

From a U.S. health-care delivery system perspective, the incremental cost-effectiveness ratio (ICER) was $22,057 per quality adjusted life year (QALY) gained. Probabilistic sensitivity analysis showed that edoxaban had an ICER <$50,000 per QALY gained relative to warfarin in 67% of model simulations. The result was robust to variation in key model parameters including the cost and disutility of warfarin monitoring.

CONCLUSION

Despite its higher drug acquisition cost, edoxaban is a cost-effective alternative to warfarin for the treatment of VTE.

Development of subcutaneous sustained release nanoparticles encapsulating low molecular weight heparin

The objective of the present research work was to prepare and evaluate sustained release subcutaneous (s.c.) nanoparticles of low molecular weight heparin (LMWH). The nanoparticles were prepared by water–in-oil in-water (w/o/w) emulsion and evaporation method using different grades of polylactide co-glycolide (50:50, 85:15), and different concentrations of polyvinyl alcohol (0.1%, 0.5%, 1%) aqueous solution as surfactant. The fabricated nanoparticles were evaluated for size, shape, zeta potential, encapsulation efficiency, in vitro drug release, and in vivo biological activity (anti-factor Xa activity) using the standard kit. The drug and excipient compatibility was analyzed by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and X-ray diffraction (XRD) studies. The formation of nanoparticles was confirmed by scanning electron microscopy; nanoparticles were spherical in shape. The size of prepared nanoparticles was found between 195 nm and 251 nm. The encapsulation efficiency of the nanoparticles was found between 46% and 70%. In vitro drug, release was about 16–38% for 10 days. In vivo drug, release shows the sustained release of drug for 10 days in rats. FTIR studies indicated that there was no loss in chemical integrity of the drug upon fabrication into nanoparticles. DSC and XRD results demonstrated that the drug was changed from the crystalline form to the amorphous form in the formulation during the fabrication process. The results of this study revealed that the s.c. nanoparticles were suitable candidates for sustained delivery of LMWH.