The risk of recurrent thromboembolic disorders in patients with unprovoked venous thromboembolism: new scenarios and opportunities

Recurrent deep vein thrombosis following brown recluse spider bite complicated by medication noncompliance and residual scar tissue: A rare case report

Clinicians should be aware of the occurrence of deep vein thrombosis following brown recluse spider bite.

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.

Prognostic characteristics and body mass index in patients with pulmonary embolism: does size matter?

Objective

The aim of this study was to explore the impact of body mass index (BMI) on prognostic indicators and clinical outcomes in patients with pulmonary embolism.

Methods

Patients with pulmonary embolism from the Hokusai venous thromboembolism (VTE) randomised clinical trial that compared two anticoagulant regimens were followed-up for 1 year (n=1911). Patients were analysed with regard to World Health Organization (WHO) BMI categories at baseline (underweight (<18.5), normal (18.5 to <25), overweight (25 to <30), obese I (30 to <35), obese II (35 to <40), and obese III (≥40)). Clinical and radiological prognostic characteristics for right ventricular dysfunction and adverse events were assessed with normal weight as a reference. Clinical outcomes were mortality, recurrent VTE, hospitalisation, bleeding and overall adverse events.

Results

The relationship between BMI categories and both prognostic parameters and clinical outcomes showed U-shaped curves. Adjusted odds ratios (aORs) were highest in patients who were grade III obese for both clinical parameters (N-terminal pro-brain natriuretic peptide (NT-proBNP) >600 and simplified pulmonary embolism severity index (sPESI)≥1; 2.9 and 1.6), and radiological parameters (pulmonary trunk>29 mm, right-to-left-ventricular ratio>1.0, and central emboli; aOR=4.3, 2.1 and 2.3). Bleeding was observed more frequently in the higher categories of obesity. In patients who were underweight, for NT-proBNP>600 and sPESI≥1 the aORs were 2.6 and 2.5, respectively; however, no major bleeding occurred in this category.

Conclusion

Several clinical and radiological prognostics characteristics and right ventricular dysfunction in pulmonary embolism are not evenly distributed among BMI categories. This is reflected in a trend towards worse outcomes in patients who are overweight and underweight.

Overweight patients with pulmonary embolism have a higher risk of heart dysfunction and worse outcomeshttp://bit.ly/2Pwtln0

Association of recurrent venous thromboembolism and circulating microRNAs

BACKGROUND

Patients with unprovoked first venous thromboembolism (VTE) are at a high risk of recurrence. Although circulating microRNAs (miRNAs) have been found to be associated with VTE and are markers of hypercoagulability, this study is the first to examine whether circulating miRNAs are associated with the risk of VTE recurrence.

RESULTS

A nested case-control study design was used where plasma samples were obtained from 78 patients with unprovoked VTE from the Malmö Thrombophilia Study (MATS). A total of 39 VTE patients with recurrent VTE (cases) were matched with 39 VTE patients without recurrent VTE (controls) defined by age and sex (MATS population). Plasma levels of 179 different miRNAs were evaluated in the 78 samples (after anticoagulant treatment was stopped) using qPCR. A total of 110 miRNAs were detected in all samples. Among those, 12 miRNAs (miR-15b-5p, miR-106a-5p, miR-197-3p, miR-652-3p, miR-361-5p, miR-222-3p, miR-26b-5p, miR-532-5p, miR-27b-3p, miR-21-5p, miR-103a-3p, and miR-30c-5p) were found to be associated with recurrent VTE after multiple correction test and conditional logistic regression analysis. A further analysis showed that miR-15b-5p, miR-197-3p, miR-27b-3p, and miR-30c-5p exhibited a trend over time, with a larger difference in miRNA levels between cases and controls for earlier recurrence. Of these 12 miRNAs, 8 miRNAs significantly correlated with circulating transforming growth factor β1/2 (TGFβ1/2). Three of them correlated with platelet count.

CONCLUSION

We have identified 12 plasma miRNAs that may have the potential to serve as novel, non-invasive predictive biomarkers for VTE recurrence.

Deep venous thrombosis in the clinical course of pulmonary embolism

Objectives

The aim of the study is to find how concomitant deep venous thrombosis (DVT) changes the clinical course of pulmonary embolism.

Methods

Three hundred and five patients with pulmonary embolism were examined and grouped into DVT and non-DVT groups. Both groups were compared with regard to demography, predisposing factors, clinical signs, thrombotic burden, and one-month mortality rate.

Results

The patients with DVT had a more severe clinical presentation: higher heart rate (94.80 ± 18.66 beats per minute versus 87.9 ± 13.90 in the non-DVT group, p = 0.00033), more hemodynamic instability (11.35% versus 3.05% in the non-DVT group, p = 0.005), and less pCO2 in arterial blood gases (30.81 ± 7.94 mmHg versus 32.59 ± 7.35 mmHg in the non-DVT group, p = 0.049). The DVT group had heavier thrombotic burden in pulmonary artery, measured by Mastora score. The one-month mortality rate did not differ statistically between groups.

Conclusions

Patients with symptomatic pulmonary embolism and concomitant DVT have heavier thrombotic burden in the pulmonary artery and more severe clinical presentation compared to those without DVT, but a similar one-month mortality rate.

Recognition of unprovoked (idiopathic) pulmonary embolism-Prospective observational study

BACKGROUND

The assessment of the clinical symptoms is the weakest link of the pulmonary embolism (PE) diagnostic algorithm. Despite the presence of highly sensitive and specific imaging methods, verifying PE remains difficult due to nonspecific clinical symptoms and frequently its subclinical course.

OBJECTIVE

The aim of this study is to improve the recognition of PE by investigating the clinical presentation and short-term prognosis of unprovoked PE in comparison to provoked PE. The study was directed to patients who suffer from PE as a primary disease.

METHODS

This prospective observational study included 331 patients with PE, approved by computer tomographic pulmoangiography. They were categorized as having unprovoked or provoked PE, according to their epidemiological data. The clinical characteristics and one-month mortality rate were compared between both groups.

RESULTS

About 67% of the patients had provoking factors and ∼33% had unprovoked PE. The patients in the unprovoked PE-group were younger compared to provoked PE-group (56.67 ± 17.95 vs 63.76 ± 14.58, p < .0001) and the males predominated vs females (62.04% vs 37.96%, p = .012). The patients with unprovoked PE had more previous thromboembolic events compared to provoked PE-group (30.56% vs 19.45%, p = .022) and a larger thrombotic burden (p = .001). Dyspnea (85.18% vs 85.13%), chest pain (47.22% vs 46.85%), cough (43.92% vs 45.94%), hemoptysis (16.67% vs 14.41%), hemodynamic instability (9.26% vs 8.56%), deep venous thrombosis (49.51% vs 44.5%) had similar frequencies in both groups. No significant differences in the means of systolic pressure of arteria pulmonalis, D-dimer, arterial blood gases, Revised Geneva probability score were found. One-month mortality was lower in unprovoked PE-group than in provoked (1.85% vs 8.52%, p = .042).

CONCLUSIONS

Unprovoked PE occurs at a younger age, more frequently in males. It is characterized by the following significant variables: higher Wells score, lower PESI score, lower CRP, higher thrombotic burden and lower one-month mortality rate, compared to provoked PE.

Whole exome sequencing in thrombophilic pedigrees to identify genetic risk factors for venous thromboembolism

BACKGROUND

Family studies have shown a strong heritability component for venous thromboembolism (VTE), but established genetic risk factors are present in only half of VTE patients.

AIM

To identify genetic risk factors in two large families with unexplained hereditary VTE.

METHODS

We performed whole exome sequencing in 10 affected relatives of two unrelated families with an unexplained tendency for VTE. We prioritized variants shared by all affected relatives from both families, and evaluated these in the remaining affected and unaffected individuals. We prioritized variants based on 3 different filter strategies: variants within candidate genes, rare variants across the exome, and SNPs present in patients with familial VTE and with low frequency in the general population. We used whole exome sequencing data available from 96 unrelated VTE cases with a positive family history of VTE from an affected sib study (the GIFT study) to identify additional carriers and compared the risk-allele frequencies with the general population. Variants found in only one individual were also retained for further analysis. Finally, we assessed the association of these variants with VTE in a population-based case-control study (the MEGA study) with 4,291 cases and 4,866 controls.

RESULTS

Six variants remained as putative disease-risk candidates. These variants are located in 6 genes spread among 3 different loci: 2p21 (PLEKHH2 NM_172069:c.3105T>C, LRPPRC rs372371276, SRBD1 rs34959371), 5q35.2 (UNC5A NM_133369.2:c.1869+23C>A), and 17q25.1 (GPRC5C rs142232982, RAB37 rs556450784). In GIFT, additional carriers were identified only for the variants located in the 2p21 locus. In MEGA, additional carriers for several of these variants were identified in both cases and controls, without a difference in prevalence; no carrier of the UNC5A variant was present.

CONCLUSION

Despite sequencing of several individuals from two thrombophilic families resulting in 6 candidate variants, we were unable to confirm their relevance as novel thrombophilic defects.

Edoxaban improves acute venous thromboembolism while preserving protein C and protein S levels

BACKGROUND

It is well known that warfarin inhibits the synthesis of vitamin K-dependent anticoagulants, including thrombin, protein C and S, and factor Xa, leading, paradoxically, to an initial hypercoagulable state. Edoxaban, a direct inhibitor of activated factor X is widely used for the treatment of acute venous thromboembolism (VTE). However, the effect of edoxaban on circulating coagulation factors, in patients with acute VTE, remains unknown.

METHODS AND RESULTS

We enrolled 57 patients with acute VTE with/without pulmonary embolism treated with edoxaban (n=37) or warfarin (n=20) in a clinical setting. Before treatment and 2 weeks after treatment, we evaluated thrombotic burden using ultrasound or computed tomography angiography. We also evaluated thrombin generation, represented by prothrombin fragment F1+2; thrombus degradation, represented by D-dimer; and levels of anticoagulants, including protein C, protein S, and antithrombin III. Both edoxaban and warfarin treatment improved thrombotic burden and decreased prothrombin fragment F1+2, and D-dimer. Edoxaban treatment preserved protein C and protein S levels. In contrast, warfarin decreased protein C and protein S levels. Neither treatment affected antithrombin III.

CONCLUSIONS

Edoxaban improves VTE while preserving protein C and protein S levels, thereby indicating that edoxaban improves thrombotic burden while maintaining levels of anticoagulants.

Thrombophilia Screening: Universal, Selected, or Neither?

The utility of thrombophilia testing in clinical practice is still a matter of debate because studies have not shown a benefit in the reduction of recurrent venous thromboembolism (VTE) risk in patients with thrombosis, despite the clearly higher VTE risk for first thrombosis. Screening for thrombophilia is indicated in selected patients. Particularly in selected young patients, especially women of childbearing age, the knowledge of the genetic thrombophilic defect may help in specific situations to decrease the risk of VTE events. Avoidance of modifiable risk factors and/or prophylactic thromboembolic procedures may be evaluated in selected patients. A comprehensive workup including personal and familial history, clinical examination, and laboratory test results including hereditary thrombophilia remains helpful in assessing the cumulative risk and the management of this group of selected patients.

Managing Extended Oral Anticoagulation After Unprovoked Venous Thromboembolism

Venous thromboembolism (VTE), which includes deep venous thrombosis and pulmonary embolism, is a major public health problem associated with increased morbidity and mortality. Despite the high recurrence risk associated with unprovoked VTE, extended anticoagulation remains controversial. Oral antithrombotic agents for extended VTE treatment comprise the vitamin K antagonists, aspirin, and the direct oral anticoagulants (also known as target-specific oral anticoagulants and formerly known as the new or novel oral anticoagulants) including rivaroxaban, dabigatran, apixaban, and edoxaban. The efficacy of these anticoagulants in reducing the risk of VTE recurrence (>80%-90% relative risk reduction) is offset by the risk of major bleeding that approaches 3% per year. Stratifying risks of recurrence and bleeding to identify patients at low, intermediate, or high risk and carefully considering the pharmacologic profile of the antithrombotic agents will help clinicians in choosing the optimal anticoagulant and duration and/or surveillance strategy. This review will discuss the current guidelines for extended VTE treatment, review the clinical trials involving the direct oral anticoagulants, and present the clinical considerations and concerns involving extended therapy.

Should lifelong anticoagulation for unprovoked venous thromboembolism be revisited?

Venous thromboembolism [VTE] is a common medical condition that has significant morbidity and mortality. Although stringent guidelines recommend lifelong anticoagulation for patients with unprovoked VTE, the optimal management strategy for their long term treatment remains controversial.

Whereas in cancer-associated VTE and second unprovoked VTE lifelong anticoagulation is universally accepted, a careful analysis of the benefit vs. risk of long-term anticoagulation following a first unprovoked VTE should be considered as case fatality rates [CFR] from VTE appear more pronounced in the first few months. The CFR from major bleeding remains constant throughout therapy. Therefore, the risk of bleeding may be underestimated over longer treatment periods relative to the morbidity of recurrent VTE which appears to peak in the first year. The current review highlights the balance between the recurrence risk and bleeding risks in the era of direct oral anticoagulants.

Vitamin K antagonists have been the standard of care for over 50 years bearing significant bleeding risks. The new oral anticoagulants [NOACs] have shown similar efficacy and perhaps a questionable improved safety profile when compared to warfarin.

Aspirin has historically not been a useful agent in the management of VTE. However, two recent trials [WARFASA and ASPIRE] showed a likely 20-30 % risk reduction when compared to placebo for recurrent VTE after initial anticoagulation. The risk of major hemorrhage was low in both trials.

With the emergence of NOACs and the increased utility of aspirin, there are multiple therapeutic options for long term management for VTE. Given comparable efficacy and improved safety of NOACs and aspirin, the risk benefit of anticoagulation is improving.

A risk stratification model may help identifying patients at high risk for recurrence necessitating a lifelong anticoagulation. This cohort should be separated from a low risk group that may benefit from clinical observation, aspirin or NOACs.

Prospective clinical trials are needed to support these clinical observations.

Venous thromboembolism in 2013: the advent of the novel oral anticoagulants

New findings published in 2013 strongly support the use of novel oral anticoagulants in the treatment of thromboembolic disorders. These drugs have been shown to have a more-favourable benefit-to-risk profile than older compounds, enabling their use from the start of treatment and in the whole spectrum of clinical presentations.