Venous thromboembolism: risk factors for recurrence

The Role of Local Flaps in Foot and Ankle Reconstruction: An Assessment of Outcomes across 206 Patients with Chronic Wounds

BACKGROUND

Reconstructive surgery has experienced a paradigm shift in favor of free flaps. Yet local flaps may be of particular use in foot and ankle reconstruction among comorbid patient populations. Thus, the authors sought to better characterize long-term outcomes in this setting.

METHODS

A single-center, retrospective cohort study of patients undergoing local muscle and fasciocutaneous flaps of the foot and ankle from January of 2010 through November of 2022 was performed. Flaps were performed on wounds measuring 3 × 6 cm or smaller; flap selection depended on preoperative vascular assessment, Doppler findings, comorbidity profile, and wound location, depth, and geometry.

RESULTS

A total of 206 patients met inclusion criteria. Their median age was 61.0 years (interquartile range, 16.8), and comorbidities included diabetes mellitus ( n = 149 [72.3%]) and peripheral arterial disease ( n = 105 [51.0%]). Presentations included chronic, nonhealing wounds ( n = 77 [39.1%]) or osteomyelitis ( n = 45 [22.8%]) and most frequently extended to the bone ( n = 128 [62.1%]). Eighty-seven patients (42.2%) received muscle flaps; 119 (57.8%) received fasciocutaneous flaps. Six patients (2.9%) needed return to the operating room, with thrombosis occurring in 2 cases (1.0%). The flap success rate was 98.1%. By a median follow-up duration of 21.7 months (interquartile range, 39.0), 21.8% of patients ( n = 45) required ipsilateral amputation, 73% ( n = 145 of 199) were ambulatory, and 2 deaths related to the surgical wound occurred (2 of 49 [4.1%]). Multivariate analysis revealed that positive predictors of complications included diabetes mellitus, end-stage renal disease, and history of venous thromboembolism or smoking.

CONCLUSION

Local flaps remain a reliable option to reconstruct smaller defects of the foot and ankle in a highly comorbid population.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Cancer-associated venous thrombosis in adults (second edition): A British Society for Haematology Guideline

A shared decision on the most appropriate agent for the treatment of cancer-associated thrombosis should consider the following factors, which should be reassessed as patients continue along their cancer care pathway: risk of bleeding; tumour site; suitability of oral medications; potential for drug-drug interactions; and patient preference and values regarding choice of drug. Continuing anticoagulation beyond 6 months in patients with cancer-associated venous thromboembolism and active cancer is recommended.

Awareness and Knowledge of Venous Thromboembolism Among Saudi Adults in the Dawadmi Province: A Cross-Sectional Study

Background Venous thromboembolism (VTE) significantly contributes to the global disease burden. The annual incidence of VTE is one to two per 1,000 adults worldwide. We aimed to evaluate the awareness and knowledge of VTE risk factors, manifestations, prevention, and treatment options among the general adult population of Dawadmi, Riyadh, Saudi Arabia. Methodology We conducted a cross-sectional study using the self-designed and validated VTE knowledge questionnaire. A survey was conducted online via Google Documents, composed of 12 questions. Participants included in the study were over 18 years old, regardless of their medical history. However, medical students and healthcare providers were excluded. Results A total of 384 participants (46.4% men and 53.6% women) completed the survey; most respondents were between 18 and 28 years of age. Majority of the participants recognized that immobility, obesity, complicated surgery, road traffic accidents, smoking, and old age are the most common risk factors for VTE. However, more than half of the elderly and lower-educated participants did not identify complicated surgery and consumption of oral contraceptive pills as risk factors for VTE. Awareness of VTE was significantly higher among those with a family history of VTE and a graduate degree (p<0.001). Results showed a deficit of awareness and information about VTE, especially among males, those with low education, and elderly participants. Conclusion This study demonstrates the need for more awareness of VTE among the Saudi adult population. The urge to spread awareness and knowledge about VTE among the public in Dawadmi province is required.

Trajectories of Oral Anticoagulation Adherence and Associated Clinical Outcomes During Long-Term Anticoagulation Among Medicare Beneficiaries With Venous Thromboembolism

BACKGROUND

Little is known about anticoagulation medication nonadherence patterns impacting effectiveness and safety outcomes in clinical practice.

OBJECTIVE

We identified adherence trajectories of extended therapy with direct-acting oral anticoagulants (DOACs) and warfarin after 6 months initial anticoagulant therapy among Medicare beneficiaries with venous thromboembolism (VTE). We further assessed the associated recurrent VTE and major bleeding risks.

METHODS

Using group-based trajectory models, this retrospective cohort study identified distinct beneficiary subgroups with similar adherence patterns of extended-phase anticoagulant treatment (DOACs or warfarin) for patients with VTE who completed 6 months of initial anticoagulant treatment. We examined associations between adherence trajectories and risks of recurrent VTE and major bleeding using inverse probability treatment weighted Cox proportional hazards models.

RESULTS

Compared with no extended treatment, consistently high DOAC adherence was associated with decreased recurrent VTE risk (hazard ratio [HR] = 0.33, 95% confidence interval [CI] = 0.21-0.51) without increased major bleeding risk, and consistently high warfarin adherence was associated with decreased recurrent VTE risk (HR = 0.62, 95% CI = 0.40-0.95) and increased major bleeding risk (HR = 1.64, 95% CI = 1.12-2.41). Gradually declining adherence to DOACs (HR = 1.80, 95% CI = 1.07-3.03) or warfarin (HR = 2.34, 95% CI = 1.57-3.47) was associated with increased bleeding risk with no change in recurrent VTE risk.

CONCLUSION AND RELEVANCE

This real-world evidence suggests persistently adhering to extended DOAC therapy is associated with lower recurrent VTE risk without increasing major bleeding among Medicare beneficiaries with VTE. Persistently adhering to extended warfarin therapy was associated with lower recurrent VTE risk but higher major bleeding risk.

Trajectories of adherence to extended treatment with direct oral anticoagulants and risks of recurrent venous thromboembolism and major bleeding

BACKGROUND: Little is known about medication adherence patterns and their association with effectiveness and safety among patients with venous thromboembolism (VTE) receiving direct oral anticoagulant (DOAC) therapy beyond 3-6 months of initial treatment. OBJECTIVE: To examine the associations between adherence trajectories of extended treatment with DOAC and the risks of recurrent VTE and major bleeding among patients with VTE. METHODS: We conducted a retrospective cohort study of patients with incident VTE who completed 6 months of initial anticoagulant treatment and received either DOAC extended therapy or no extended therapy using MarketScan Commercial and Medicare Supplemental databases (2013-2019). We used group-based trajectory models to identify distinct adherence patterns during extended treatment. Using inverse probability treatment weighted Cox proportional hazards models, we examined the association between the adherence trajectories and the risks of recurrent VTE and major bleeding. RESULTS: Among 10,960 patients with extended treatment with DOACs (rivaroxaban, apixaban, dabigatran, edoxaban) and 5,133 patients with no extended treatment, we identified 4 distinct trajectories (consistently high, gradually declining, rapidly declining, and no extended treatment). Compared with the no extended treatment group, the groups with consistently high adherence (hazard ratio = 0.09, 95% CI = 0.05-0.17) and with gradually declining adherence (0.13, 0.03-0.53) showed decreased recurrent VTE risk without increased major bleeding risk (consistently high adherence 1.19, 0.71-1.99; gradually declining adherence 1.96, 0.81-4.70). There was no difference in the risk of recurrent VTE (0.34, 0.10-1.16) for the group with rapidly declining adherence, but this group was associated with increased major bleeding risk (2.65, 1.01-6.92). CONCLUSIONS: Our findings underscore the clinical importance of continuing and remaining adherent to extended DOAC treatment without increased major bleeding risk for patients with VTE. DISCLOSURES: This research was supported by the BMS/Pfizer Alliance American Thrombosis Investigator Initiated Research Program. The funding source had no role in the design, collection, analysis, or interpretation of the data or the decision to submit the article for publication. Dr Lo-Ciganic reported receiving research funding from Merck Sharp & Dohme Corp. Dr Dietrich reported receiving honorarium for training and education from BMS/Pfizer. Dr DeRemer is a stockholder of Portola Pharmaceuticals and reported receiving personal fees for advisory board meeting from BMS. No other disclosures were reported.

Hand grip strength in venous thromboembolism: risk of recurrence and mortality

Background

There is limited information on the relationship between muscle strength and recurrence and mortality after incident venous thromboembolism (VTE).

Objectives

To investigate whether weak hand grip strength (HGS) was associated with risk of recurrence and mortality in patients with VTE recruited from the general population.

Methods

Participants from the Tromsø Study with a first-time VTE (n = 545) were included, and all VTE recurrences and deaths among the participants were recorded in the period 1994 to 2020. Weak HGS was defined as lowest 25th percentile of the general population, and incidence rates for VTE recurrence and mortality according to weak vs normal (>25th percentile) HGS, with 95% CIs, were estimated.

Results

There were 90 recurrences and 350 deaths during a median of 3.7 years of follow-up. The fully adjusted hazard ratio (HR) for overall VTE recurrence for those with weak HGS vs those with normal HGS was 2.02 (95% CI, 1.23-3.30). The corresponding HRs for recurrence were 2.22 (95% CI, 1.18-4.17) in patients with a first deep vein thrombosis and 1.60 (95% CI, 0.72-3.57) in patients with a first pulmonary embolism. The cumulative 1-year survival was 74.9% and 77.8% in those with weak and normal HGS, respectively. For overall mortality after incident VTE, the fully adjusted HR for those with weak HGS was 1.34 (95% CI, 1.04-1.72).

Conclusion

Weak HGS was associated with an increased risk of recurrent VTE, and the association appeared to be particularly pronounced after incident deep vein thrombosis. There was a slightly lower survival probability among those with weak HGS than among those with normal HGS.

Prevention, Diagnostics and Treatment of Deep Vein Thrombosis. Russian Experts Consensus

The guidelines are developed in accordance with the requirements of the Ministry of Health of the Russian Federation by the all-Russian public organization «Association of Phlebologists of Russia» with participation of the Association of Cardiovascular Surgeons of Russia, the Russian Society of Surgeons, the Russian Society of Angiologists and Vascular Surgeons, the Association of Traumatologists and Orthopedists of Russia, the Association of Oncologists of Russia, the Russian Society of Clinical Oncology, Russian Society of Oncohematologists, Russian Society of Cardiology, Russian Society of Obstetricians and Gynecologists.

Association of ABO blood groups with venous thrombosis recurrence in middle-aged patients: insights from a weighted Cox analysis dedicated to ambispective design

BACKGROUND

In studies of time-to-events, it is common to collect information about events that occurred before the inclusion in a prospective cohort. When the studied risk factors are independent of time, including both pre- and post-inclusion events in the analyses, generally referred to as relying on an ambispective design, increases the statistical power but may lead to a selection bias. In the field of venous thromboembolism (VT), ABO blood groups have been the subject of extensive research due to their substantial effect on VT risk. However, few studies have investigated their effect on the risk of VT recurrence. Motivated by the study of the association of genetically determined ABO blood groups with VT recurrence, we propose a methodology to include pre-inclusion events in the analysis of ambispective studies while avoiding the selection bias due to mortality.

METHODS

This work relies on two independent cohorts of VT patients, the French MARTHA study built on an ambispective design and the Dutch MEGA study built on a standard prospective design. For the analysis of the MARTHA study, a weighted Cox model was developed where weights were defined by the inverse of the survival probability at the time of data collection about the events. Thanks to the collection of information on the vital status of patients, we could estimate the survival probabilities using a delayed-entry Cox model on the death risk. Finally, results obtained in both studies were then meta-analysed.

RESULTS

In the combined sample totalling 2,752 patients including 993 recurrences, the A1 blood group has an increased risk (Hazard Ratio (HR) of 1.18, p = 4.2 × 10^-3) compared with the O1 group, homogeneously in MARTHA and in MEGA. The same trend (HR = 1.19, p = 0.06) was observed for the less frequent A2 group.

CONCLUSION

The proposed methodology increases the power of studies relying on an ambispective design which is frequent in epidemiologic studies about recurrent events. This approach allowed to clarify the association of ABO blood groups with the risk of VT recurrence. Besides, this methodology has an immediate field of application in the context of genome wide association studies.

Impact of venous thromboembolism on incidence of arterial thromboembolism - An analysis of German outpatient claims data

BACKGROUND

Venous thromboembolism (VTE) and arterial thromboembolism (ATE) are considered as two separate disease-entities. In recent years, studies have reported clear associations between VTE and atherosclerosis. We aimed to evaluate the long-term risk of ATE in VTE patients in comparison to controls without VTE.

METHODS

Nationwide outpatient claims data of all inhabitants with statutory health insurance in Germany were used for secondary data analysis between the years 2011 and 2020. Patients treated in 2013 were stratified by VTE event, and groups were 1:2-matched by age and sex. The hazard for an ATE event in a 5-year follow-up period between patients with and without VTE was calculated with multivariable Cox regression adjusted for age, sex, cardiovascular risk factors, and comorbidities.

RESULTS

Of 69,699,277 individuals treated in the year 2013 by German physicians in outpatient care, in total 686,382 individuals (age 59.8 ± 17.5 years, 65.4 % females) were included comprising 228,794 patients with VTE and 457,588 controls without VTE. VTE patients more often had cardiovascular risk factors (81.6 % vs. 62.2 %) and traditional VTE risk factors. The occurrence of ATE events during follow-up was 1.8 %-points higher in VTE patients in comparison to the controls (9.7 % vs. 7.9 %). VTE events were independently associated with increased occurrence of ATE events within follow-up (HR_adjusted 1.19 [99%CI 1.16-1.23], p < 0.0001).

CONCLUSIONS

Patients with a VTE event have an increased long-term risk for subsequent arterial cardiovascular events. Large prospective cohorts are needed to identify patient subgroups with a very high ATE risk after VTE.

Residual pulmonary vascular obstruction and recurrence after acute pulmonary embolism: a systematic review and meta-analysis of individual participant data

We aimed to assess the relationship between residual pulmonary vascular obstruction (RPVO) on planar lung scan after completion of at least 3 months of anticoagulant therapy for acute pulmonary embolism (PE) and the risk of recurrent venous thromboembolism (VTE) or death due to PE one year after treatment discontinuation. The systematic review was registered with the International Prospective Registry of Systematic Reviews (PROSPERO: CRD42017081080). The primary outcome measure was to generate a pooled estimate of the rate of recurrent VTE at one year in patient with RPVO diagnosed on planar lung scan after discontinuation of at least 3 months of anticoagulant treatment for an acute PE. Individual data were obtained for 809 patients. RPVO (ie, obstruction >0%) was found in 407 patients (50.3%) after a median of 6.6 months of anticoagulant therapy for a first acute PE. Recurrent VTE or death due to PE occurred in 114 patients (14.1%), for an annual risk of 6.4% (95% confidence interval, 4.7%-8.6%). Out of the 114 recurrent events, 63 occurred within one year after discontinuation of anticoagulant therapy corresponding to a risk of 8.1% (6.4%-9.8%) at 1 year. The risk of recurrent VTE at one year was 5.8% (4.4-7.2) in participants with RPVO <5%, vs 11.7% (9.5-13.8) in participants with RPVO ≥5%. RPVO is a significant predictor of the risk of recurrent venous thromboembolism. However, the risk of recurrent events remains too high in patients without residual perfusion defect for it to be used as a stand-alone test to decide on anticoagulation discontinuation.

Underlying mechanisms of thrombus formation/growth in atherothrombosis and deep vein thrombosis

Thrombosis remains a leading cause of death worldwide despite technological advances in prevention, diagnosis, and treatment. The traditional view of arterial thrombus formation is that it is a platelet-dependent process, whereas that of venous thrombus formation is a coagulation-dependent process. Current pathological and basic studies on atherothrombosis and venous thrombosis have revealed the diverse participation of platelet and coagulation activation mechanisms in both thrombus initiation and growth processes during clinical thrombotic events. Atherosclerotic plaque cell-derived tissue factor contributes to fibrin formation and platelet aggregation. The degree of plaque disruption and a blood flow alteration promote atherothrombotic occlusion. While blood stasis/turbulent flow due to luminal stenosis itself initiates venous thrombus formation. The coagulation factor XI-driven propagation phase of blood coagulation plays a major role in venous thrombus growth, but a minor role in hemostasis. These lines of evidence indicate that atherothrombosis onset is affected by the thrombogenic potential of atherosclerotic plaques, the plaque disruption size, and an alteration in blood flow. Upon onset of venous thrombosis, enhancement of the propagation phase of blood coagulation under blood stasis and a hypercoagulable state contribute to large thrombus formation.

Patients with severe coronavirus disease 2019 have high frequency of factor 5 Leiden and prothrombin gene mutations

We investigated the frequency of factor 5 Leiden (FVL) and prothrombin gene (PTG) mutations in patients with severe coronavirus disease 2019 (COVID-19). Our primary aim is to reveal whether these mutations are associated with severity of disease and mortality. A total of 249 patients were included in this cross-sectional study. Severe COVID-19 cases (with oxygen saturation of less than 90 mmHg and who received ventilation support invasively or noninvasively) were included. FVL and PTG mutations were identified by real time- PCR technique. Frequency of mutations for FVL was 11.7%, whereas for PTG was 3.5%. The frequency of FVL and PTG's mutations in our patient group was found to be significantly higher than the normal population ( P  < 0.0001, 0.004, respectively). There was no difference in the frequency of mutations of FVL and PTG between the patients ventilated - invasively and noninvasively. There was also no difference in D-dimer, ferritin, fibrinogen, ex status, and entubational status between the groups of FVL and PTG mutated and wild-type. To the best of our knowledge, it is the first time that we have examined the frequencies of FVL and PGM's mutations in severe COVID-19 disease on such a large scale. The frequencies of both mutations in severe COVID-19 patients were higher than in the healthy population. We believe that studies prospectively designed, including asymptomatic and mild COVID-19 patients, will provide more comprehensive information on the subject.

Comparative effectiveness and safety of extended anticoagulant therapy among Medicare beneficiaries with venous thromboembolism

Guidelines recommend an extended course of anticoagulation therapy for patients who experienced venous thromboembolism (VTE) without transient provocation, however, optimal duration remains uncertain. We assessed effectiveness and safety of extended use of apixaban and warfarin greater than 6 months of initial treatment in patients with VTE. We conducted a retrospective cohort study of Medicare beneficiaries aged greater than or equal to 18 years with deep vein thrombosis or pulmonary embolism. Patients were required to have initiated anticoagulants within 30 days of their first VTE diagnosis, completed 6 months of initial anticoagulant treatment, and received extended phase treatment with apixaban (the apixaban group) or warfarin (the warfarin group) or no extended therapy. Multivariable Cox proportional hazards modeling with inverse probability treatment weighting was used to compare recurrent VTE, mortality, and major bleeding risks among the three groups. Mean extended-treatment duration was up to 10 months and 14 months in apixaban and warfarin groups, respectively. Compared with no extended treatment, apixaban use was associated with decreased risks of recurrent VTE (hazard ratio [HR] = 0.08, [95% confidence interval [CI]: 0.01-0.41]) and mortality (HR = 0.37, [95% CI: 0.27-0.51]) without increased major bleeding risk (HR = 1.29, [95% CI: 0.68-2.45]); warfarin use was associated not with recurrent VTE risk change but with increased major bleeding risk (HR = 2.14, [95% CI: 1.26-3.65]) and decreased mortality risk (HR = 0.39, [95% CI: 0.29-0.51]). Compared with warfarin, apixaban use was associated with decreased recurrent VTE (HR = 0.13, [95% CI: 0.03-0.63]) and major bleeding (HR = 0.56, [95% CI: 0.32-0.98]) risks. Subgroup and sensitivity analyses (e.g., intention-to-treat) findings remained consistent. Compared with warfarin or no extended therapy, extended-apixaban use was associated with reduced risk of recurrent VTE without increased major bleeding risk. Continuing anticoagulant therapy with apixaban greater than 6 months may be effective and safe.

Clinical epidemiology of venous thromboembolic disease: An institutional registry

Introduction

Venous thromboembolism (VTE) is a major health concern, with an annual incidence of ~1 in 1,000. The epidemiology of VTE in Saudi Arabia has not been adequately described yet. Therefore, this study aimed to assess the clinical characteristics, risk factors, diagnostic methods, management, and clinical outcomes of patients with VTE.

Methods

This study was based on a VTE registry created over ten years at King Fahad Medical City (KFMC) in Riyadh, Saudi Arabia. All adult inpatients and outpatients referred to the thrombosis unit of the KFMC with clinically suspected VTE including pulmonary embolism (PE) and deep vein thrombosis (DVT) were enrolled. Data were collected using a standardized case report form, which included demographic and clinical characteristics, risk factors, diagnostic methods, management, and outcomes.

Results

A total of 1,008 patients were recruited. Most patients were women (73.2%), and more than half of all patients had unprovoked VTE (58%). Among the provoked cases, the most frequent cause was surgery (29.8%), followed by hospitalization (24.2%). There was a significant statistical association between provoked status and sex, family history of VTE, smoking, recent hospitalization within 3 months for a medical condition, the site of VTE, and underlying peripheral vascular disease and varicose veins (all p &lt; 0.05). The majority (88.3%) of patients with deep vein thrombosis was hospitalized for ≤3 days (n = 433, 79.9%), while fewer than half of the patients with PE needed hospitalization (45.3%). Thrombolytic therapy was administered to 14.1% (n = 142) of patients, and catheter-directed thrombolysis was performed in 1.0% (n = 10) of patients. The odds of mortality for provoked VTE were 3.20 times higher than those of unprovoked VTE [2.12–4.83; p-value &lt; 0.001].

Conclusion

Unprovoked VTE was more common than provoked VTE in the Saudi Arabian cohort, implying hereditary predisposition. Furthermore, male sex, family history of VTE, prior history of VTE, type of VTE, underlying obesity, history of trauma, surgery, hospitalization, pregnancy, and 3–6 months of anticoagulation therapy were the most critical risk factors for VTE recurrence. The treatment patterns and clinical results were comparable to those reported in the literature.

Effectiveness and Safety of Extended Oral Anticoagulant Therapy in Patients with Venous Thromboembolism: A Retrospective Cohort Study

Limited real-world evidence exists for effectiveness and safety of extended oral anticoagulation beyond 6 months of initial treatment in prevention of recurrent venous thromboembolism (VTE) and adverse major bleeding events among patients with VTE. Using MarketScan Commercial and Medicare Supplemental databases (2013-2019), we conducted a retrospective cohort study to compare the risk of recurrent VTE and major bleeding events during extended treatment among patients with VTE who completed the 6-month initial treatment and received extended oral anticoagulant treatment with apixaban, warfarin, or no extended treatment. Hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated using Cox proportional hazards modeling with inverse probability treatment weighting. We identified 14,818 patients with extended treatment of apixaban (n = 4,338), warfarin (n = 5,298), or no extended treatment (n = 5,182). Compared with no extended treatment, apixaban use was associated with decreased risk of recurrent VTE (HR: 0.10, 95% CI: 0.04-0.26) without increased risk of major bleeding events (HR: 1.06, 95% CI: 0.52-2.17); warfarin use was associated with decreased risk of recurrent VTE (HR: 0.23, 95% CI: 0.12-0.44) but with increased risk of major bleeding events (HR: 2.64, 95% CI: 1.51-4.59). Compared with warfarin, apixaban use was associated with decreased risk of major bleeding events (HR: 0.42, 95% CI: 0.22-0.80) but no difference in risk of recurrent VTE (HR: 0.46, 95% CI: 0.15-1.36). In a real-world clinical setting, extended anticoagulation with apixaban or warfarin was associated with decreased risk of recurrent VTE compared with no extended treatment, and apixaban had a better safety profile with fewer major bleeding events compared with warfarin among commercially insured patients with VTE.

Treatment and secondary prophylaxis of venous thromboembolism in cancer patients

Cancer-associated thrombosis (CAT) adversely affects the quality of life and survival of people with cancer. A holistic approach is optimal for the treatment and secondary prophylaxis of venous thromboembolism (VTE) including shared decision-making around anticoagulation, considering individual risk factors for VTE recurrence, morbidities from VTE, and resources available in cancer centres around the world. Taking a global perspective on availability and cost, this paper guides the reader through the wider aspects of treatment and secondary thromboprophylaxis which, in turn, influence the recent international guidelines.

Atherosclerosis and Its Impact on the Outcomes of Patients with Deep Venous Thrombosis

Introduction: Atherosclerosis and pulmonary embolism (PE) affect cardiovascular mortality substantially. We aimed to investigate the impact of atherosclerosis on the outcomes of patients with deep venous thrombosis (DVT) and to identify the differences in DVT patients with and without PE. Methods: Patients with DVT with and without symptomatic atherosclerosis (defined as coronary artery disease, myocardial infarction and/or peripheral artery disease) as well as with and without PE under oral anticoagulation were enrolled during January 2011−April 2013 and compared. The impact of symptomatic atherosclerosis on several outcomes was analyzed. Results: Overall, 509 DVT patients (70.0 [56.0−77.0] years, 51.9% females) were included in this study. Among them, 179 (36.3%) had symptomatic atherosclerosis and 204 (40.1%) a concomitant PE. DVT patients with symptomatic atherosclerosis were older (74.0 [IQR 65.0−80.0] vs. 63.0 [48.0−75.0] years, p < 0.0001), more often male (56.4% vs. 43.9%, p = 0.0087) and had a higher prevalence of classical CVRF and a higher Charlson comorbidity index (7.00 [5.00−8.00] vs. 4.00 [2.00−6.00], p < 0.001). Symptomatic atherosclerosis was associated with increased mortality (HR 1.98 [95%CI 1.12−3.49], p = 0.018) and hospitalizations (HR 1.64 [95%CI 1.21−2.21], p = 0.0012) and primary long-term outcome (HR 1.99 [95%CI 1.31−3.04], p = 0.0013) during the 2 years follow-up-period in DVT patients. DVT patients without PE had diabetes mellitus (28.2% vs. 16.3%, p < 0.01) and symptomatic atherosclerosis (42.9% vs. 26.4%, p < 0.001) more often compared to DVT patients with PE, and symptomatic atherosclerosis was associated with isolated DVT (without PE) (OR 2.01 [95%CI 1.28−3.16], p < 0.01). Conclusions: Atherosclerosis was associated with isolated DVT (without PE) and increased mortality in DVT patients under oral anticoagulation. The profile of CVRF and comorbidities differed between DVT patients with and without a concomitant PE. In the case of DVT or PE, patients should be screened for concomitant atherosclerotic disease. Clinical Trial Registration: at clinicaltrials with Unique identifier NCT01809015.

Current Knowledge on Factor V Leiden Mutation as a Risk Factor for Recurrent Venous Thromboembolism: A Systematic Review and Meta-Analysis

Background

Thrombophilia screening is widely done in clinical practice, and it is claimed that the extent of venous thromboembolism (VTE) recurrence risk in patients with common defects is still not fully understood.

Aim

We aimed to summarize data of all observational studies prospectively assessing the association of heterozygous factor V Leiden (FVL) mutation and recurrent VTE in patients with VTE, and to calculate pooled relative risks (RR), overall and in various subgroups.

Methods

We searched MEDLINE and EMBASE databases for cohort studies prospectively assessing VTE recurrence in patients with and without FVL mutation (PROSPERO: CRD42021182800). Data were extracted on cohort and study-level. The methodological quality was assessed using the Newcastle-Ottawa Scale (NOS). RR were calculated overall and in subgroups using a random-effects model.

Results

From 31 cohorts, 24 studies were finally included summarizing 13,571 patients. Heterozygous FVL mutation was identified in 2,840 individuals (21%). The methodological quality was estimated to be high in 20 studies (83%). The overall RR was 1.46 (95% CI: 1.31, 1.64), consistent across subgroups.

Conclusions

Pooling all high-quality epidemiological data, the risk of recurrent VTE was increased by 46% in patients with heterozygous FVL mutation. Against the background of established risk factors, the FVL mutation plays only a marginal role in the risk assessment for recurrent VTE.

Characteristics of thromboprophylaxis in elderly patients before and after orthopedic hip and knee surgery

Elderly patients with a hip fracture are at significantly higher risk for developing venous thromboembolism (VTE). The incidence of fatal pulmonary embolism (PE) occurs in 2-3% of patients after elective hip and knee surgery and about 6-7% after hip fracture surgery, with a higher risk in men (10,2%) than in women (4,7%). The use of pharmacological prophylaxis significantly reduces the incidence of symptomatic VTE. Pharmacological prophylaxis includes the use of antiplatelet drugs (aspirin), unfractionated heparin (UFH), low molecular weight heparins (LMWH), vitamin K antagonists (VKA), Fondaparinux and direct oral anticoagulants (DOAC). The use of low molecular weight heparins (LMWH) - enoxaparin, represents the gold standard of thromboprophylaxis in orthopedic surgery, and for now, they are the only drugs that are recommended for thromboprophylaxis in hip fracture surgery. Rivaroxaban is used in the prophylaxis of VTE in elective hip and knee surgeries at a fixed dose of 10 mg once daily, and apixaban at a dose of 2,5 mg twice daily in knee arthroplasty for at least 14 days, and after hip arthroplasty for at least 35 days. Early hip fracture surgery as soon as possible, preferably within 24 hours, and no later than 48 hours after admission to the hospital, significantly reduces the morbidity and mortality of elderly patients.

Impact of Systemic Atherosclerosis on Clinical Characteristics and Short-term Outcomes in Patients with Deep Venous Thrombosis or Thrombophlebitis

BACKGROUND

Venous thromboembolism (VTE) and atherosclerosis are accompanied by substantial cardiovascular mortality; links between both disease entities were reported. We aimed to investigate the impact of systemic atherosclerosis on adverse outcomes in patients with deep venous thrombosis or thrombophlebitis (DVT) and to identify differences in DVT patients with and without systemic atherosclerosis.

METHODS

The German nationwide inpatient sample was used for this analysis. Patients admitted for DVT were included in this study and stratified by systemic atherosclerosis (composite of coronary artery disease, myocardial infarction, ischemic stroke, and/or atherosclerotic arterial diseases). We compared DVT patients with (DVT+Athero) and without (DVT-Athero) systemic atherosclerosis and analysed the impact of systemic atherosclerosis on adverse outcomes.

RESULTS

Overall, 489,679 patients with DVT (55.7% females) were included in this analysis. Among these, 53,309 (10.9%) were coded with concomitant systemic atherosclerosis with age-dependent incline. Concomitant PE (4.1% vs.3.8%, P=0.001) was more frequently in DVT-Athero and risk for PE in DVT patients was independently associated with absence of systemic atherosclerosis (OR 0.87 [95%CI 0.83-0.91], P<0.001). In-hospital mortality (3.4% vs.1.4%, P<0.001) and adverse in-hospital events (2.2% vs.0.8%,P<0.001) were more prevalent in DVT+Athero compared to DVT-Athero; both, in-hospital mortality (OR 1.52 [95%CI 1.41-1.63], P<0.001) and adverse in-hospital events (OR 1.49 [95%CI 1.40-1.58], P<0.001) were affected independently of sex, age and comorbidities by systemic atherosclerosis.

CONCLUSIONS

Systemic atherosclerosis in DVT patients was accompanied by poorer outcomes. Systemic atherosclerosis was associated with higher bleeding rate and with isolated DVT (without concomitant PE).

The treatment effect of rivaroxaban on clot characteristics in patients who present acutely with first time deep vein thrombosis

BACKGROUND

The acute vascular disease deep vein thrombosis (DVT) requires oral anticoagulants to prevent progression. Monitoring therapeutic efficacy of direct oral anticoagulants (DOAC), including rivaroxaban, is problematic as no reliable test is available. Advances in rheometry have led to the development of a functional coagulation biomarker using Gel Point (GP) analysis which assesses clot structure formation. The biomarker measures incipient clot formation time (TGP) and quantifies fibrin clot structure in terms of fractal dimension (df).

OBJECTIVE

This study aimed to investigate clot structure formation in first time DVT and the effect of rivaroxaban treatment.

METHODS

This prospective observational cohort study measured the GP and standard laboratory markers at three sample points: pre-treatment and at 20 and 60 days following 15 mg BD and 20 mg OD rivaroxaban respectively.

RESULTS

Forty DVT patients (mean age 64 years [SD±14.8]; 23 males, 17 female) were recruited. The results show that DVT vs non-DVT patients did not have a significantly different GP profile (df: 1.72±0.06 vs 1.70±0.06 and TGP: 267±68 sec vs 262±73 sec) with both within the defined healthy index. In addition, rivaroxaban therapy increased TGP to 392 s (±135 s) after 20 days, and subsequently increased to 395 s (±194 s) at 60 days but did not significantly increase df (from 1.69±0.05 to 1.71±0.06).

CONCLUSIONS

The results indicate in this cohort of DVT patients there was no underlying hypercoagulable effect as determined by gel point analysis. Furthermore, the anticoagulant effect of rivaroxaban prolonged clotting, suggesting a protective effect against clot formation, without significantly reducing clot microstructural properties.

Hyponatremia-Long-Term Prognostic Factor for Nonfatal Pulmonary Embolism

Over recent years, studies have shown that in patients with left-sided heart failure, arterial hypertension, and acute coronary syndrome, hyponatremia is a negative prognostic factor. In this context, there is raising interest in the association between hyponatremia and pulmonary embolism (PE). This retrospective cohort study includes 404 consecutive patients with confirmed acute nonfatal pulmonary embolism divided into four groups according to their sodium fluctuation pattern. The primary outcome was all-cause mortality and determining the recurrence rate among patients with nonfatal PE using serum sodium levels as a continuous variable. Patients with acquired and persistent hyponatremia had a significantly higher rate of mortality rate than those in the normonatremia group (12.8% and 40.4%, OR- 7.206, CI: 2.383-21.791, p = 0.000 and OR-33.250, CI: 11.521-95.960, p = 0.000 vs. 2%, p < 0.001, respectively). Mean survival time decreases from 23.624 months (95% CI: (23.295-23.953)) in the normonatremia group to 16.426 months (95% CI: (13.17-19.134)) in the persistent hyponatremia group, statistically significant (p = 0.000). The mean survival time for all patients was 22.441 months (95% CI: (21.930-22.951)). The highest recurrence rate was recorded at 12 and 24 months in the acquired hyponatremia group (16.7% and 14.1%, respectively). Serum sodium determination is a simple and cost-effective approach in evaluating the short and long-term prognosis in patients with acute PE.

Effect of statins on the risk of recurrent venous thromboembolism: A systematic review and meta-analysis

BACKGROUND

Recent studies have suggested that statins may be associated with a lower risk of recurrent venous thromboembolism (VTE).

METHODS

We systematically searched PubMed, Web of Science and Cochrane Library from inception until May 2020 to identify any eligible studies that reported the association between statin use and the risk of recurrent VTE, and conducted a comprehensive systematic review and meta-analysis (PROSPERO registration number: CRD42020190169) on this matter.

RESULTS

A total of 14 observational studies were included for qualitative review and 12 of them qualified for meta-analyses. The main meta-analysis found that statin use was associated with a lower risk of disease recurrence among patients with VTE (pooled adjusted HR: 0.76, 95% CI: 0.69-0.83), which was robust in sensitivity analyses and free of significant publication bias. Additionally, such association was present when restricting to periods after anticoagulation withdrawal (pooled adjusted HR: 0.78, 95% CI: 0.70-0.88) and when separately analyzing recurrent deep vein thrombosis (pooled adjusted HR: 0.71, 95% CI: 0.62-0.81) and recurrent pulmonary embolism (pooled adjusted HR: 0.80, 95% CI: 0.66-0.97; P = 0.027). Furthermore, statin use in patients with VTE was also found to be associated with a lower risk of all-cause mortality (adjusted HR: 0.65, 95% CI: 0.56-0.77), and possibly an even lower risk of bleeding (adjusted HR: 0.88, 95% CI: 0.73-1.07), albeit not statistically significant.

CONCLUSION

Statins have the potential to reduce recurrent events among patient with VTE. Randomized clinical trials to better explore the effect of statins in secondary prevention of VTE are warranted.

Risk factors associated with deep venous thrombosis in patients with different bed-rest durations: A multi-institutional case-control study

BACKGROUND

Deep vein thrombosis represents a threat to public health and a heavy economic burden to society, and often occurs as a complication or cause of death in bedridden patients. How to prevent deep vein thrombosis is a general concern in clinical practice. However, it remains uncertain whether the risk factors for deep vein thrombosis would be affected by different bed-rest durations. Solving this issue will be invaluable for the provision of more rational medical care to prevent deep vein thrombosis.

OBJECTIVE

To explore whether risk factors for deep vein thrombosis are affected by bed-rest durations and to identify different risk factors in groups with different bed-rest durations.

DESIGN

A retrospective multicenter case-control study.

SETTINGS AND PARTICIPANTS

This multicenter study was conducted in wards with high rates of bed rest in 25 general hospitals in China. Participants were bedridden patients from these wards.

METHODS

Bedridden patients were identified from the research database of bedridden patients' major immobility complications. These data were collected from prospective descriptive studies by a standardized web-based online case report form. Cases were defined as bedridden patients who suffered deep vein thrombosis during hospitalization (n=186). Each case was matched with three controls, bedridden patients who did not suffer deep vein thrombosis in the same center with the same bed-rest duration (n=558). Descriptive statistics, univariate analysis, and multivariate conditional logistic regression models were employed.

RESULTS

Among 23,985 patients, the overall incidence of deep vein thrombosis during hospitalization was 1.0%. Multivariate analysis showed that for patients with bed-rest duration of 4 weeks or less, older age (odds ratio [OR] =1.027, 95% confidence interval [CI] 1.013-1.041) and being in a surgical department (OR=2.527, 95% CI 1.541-4.144) were significantly associated with increased risk of deep vein thrombosis. Female sex (OR=4.270, 95% CI 1.227-14.862), smoking (OR=10.860, 95% CI 2.130-55.370), and special treatment (OR=3.455, 95% CI 1.006-11.869) were independent factors predicting deep vein thrombosis for patients with bed-rest durations from 5 to 8 weeks. For those with bed-rest durations from 9 to 13 weeks, Charlson Comorbidity Index (OR=1.612, 95% CI 1.090-2.385) was the only independent risk factor for deep vein thrombosis.

CONCLUSIONS

Risk factors for deep vein thrombosis varied among patients with different bed-rest durations. This finding is helpful for nurses to increase their awareness of prevention of deep vein thrombosis in patients with different bed-rest durations, and lays a more solid foundation for clinical decision making.

Comparative Effectiveness and Safety of Direct-acting Oral Anticoagulants and Warfarin in Patients with Venous Thromboembolism and Active Cancer: An Observational Analysis

PURPOSE

There is limited evidence to support the use of direct-acting oral anticoagulants (DOACs) in patients with venous thromboembolism (VTE) and active cancer. This study aimed to assess the effectiveness of DOACs versus warfarin for the prevention of recurrent VTE and major bleeding events in patients with VTE and active cancer.

METHODS

We identified patients with incident VTE and active cancer who newly initiated treatment with DOACs or warfarin from Truven Health MarketScan Commercial Claims and Medicare supplemental databases. Patients were followed up from treatment initiation (index date) until the occurrence of >7-day gap in treatment, the start of the study comparator, an outcome of interest (recurrent VTE or major bleeding), inpatient death, disenrollment, or end of the study period, whichever occurred first. We controlled for confounders via propensity score matching and estimated the hazard ratios (HRs) using Cox proportional hazards regression models.

FINDINGS

A total of 9952 patients were included in the matched cohort (4976 DOACs users and 4976 warfarin users). Patient characteristics were well balanced after matching. We observed a lower incidence of recurrent VTE (3 vs 5 per 100 person-years) and major bleeding events (2 vs 3 per 100 person-years) in the DOAC group compared to warfarin group, respectively. In Cox regression models, use of DOACs (vs warfarin) was associated with a lower risk of recurrent VTE (hazard ratio (HR), 0.59; 95% CI, 0.42-0.82) and major bleeding events (HR, 0.64; 95% CI, 0.44-0.94).

IMPLICATIONS

On the basis of our findings, among patients with VTE and active cancer, DOACs offer superior effectiveness with a lower risk of bleeding when compared with warfarin for the secondary prevention of VTE.

Randomized Trial of Deep Vein Thrombosis Chemoprophylaxis with Bemiparin and Enoxaparin in Patients with Moderate to High Thrombogenic Risk Undergoing Plastic and Reconstructive Surgery Procedures

BACKGROUND

Deep vein thrombosis (DVT) is a common complication during postoperative convalescence characterized by hypercoagulability, vascular endothelium damage and blood stasis. It increases noticeably in peri/postoperative phases of surgery procedures. Pulmonary embolism secondary to iliofemoral DVT is a frequent cause of death.

METHODS

Adult patients scheduled for plastic and reconstructive surgery (PRSx) with moderate to high thrombogenic risk were selected. We evaluated the efficacy and safety of bemiparin compared to enoxaparin as chemoprophylaxis for DVT. Following balanced general anesthesia techniques, patients were randomly assigned for subcutaneous enoxaparin 40 IU (Group-E) or bemiparin 3500 IU (Group-B) q24h starting 6 h after procedure conclusion for at least 10 days. All patients were evaluated for DVT through Doppler ultrasound mapping of the lower limbs.

RESULTS

Seventy-eight patients were evaluated, mostly women (83%), physical status ASA II (59%), ASA III (10%); Caprini's thrombogenic risk score 3-4 (moderate) 58%, 5-6 (high) 29%, > 6 (too high) 13%; demographics, clinical variables and scores were similar between groups. Median drainage time in breast surgery was 4 days in both groups (p = 0.238). In the case of abdominal surgery, median was 14 days in Group-E versus 13 days in Group-B (p = 0.059). No DVT was detected in either group.

CONCLUSIONS

DVT was prevented with bemiparin, without significant bleeding increase nor adverse events; moreover, the cost of bemiparin is lower than enoxaparin. Bemiparin can be considered as alternative drug for DVT chemoprophylaxis in PRSx procedures.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Consistency of thrombophilia testing in a reference center according to the current guidelines

OBJECTIVE

The clinical relevance of hereditary thrombophilia (HT) testing in venous thromboembolic disease (VTE) is limited to specific guidelines. The present study aimed to evaluate the consistency of HT prescriptions in clinical practice according to the current French guidelines.

METHODS

This study was conducted from April 2017 to February 2018 in a specialized haemostasis centre and included 58 consecutive patients referred by their clinicians for thrombophilia screening (56 patients following a personal VTE event and 2 asymptomatic relatives of a first-degree patient who had had VTE). One experienced clinician met every patient and assessed a pre-test prediction for the presence or absence of HT based on the clinical characteristics of VTE which was compared to the HT biological results.

RESULTS

Among the 58 patients referred to our specialized haemostasis centre, 60% were outside the scope of recommendations for thrombophilia screening. Eight patients were diagnosed with HT. Six out of 8 (75%) patients with diagnosed HT had a history of unprovoked VTE event. Familial history with VTE was a poor predictor for positive HT testing among relatives. The positive and negative predictive values of the clinical prediction were respectively of 19% and 89%.

CONCLUSION

The present results underline that screening for HT remains too largely prescribed. Pre-test physician's feeling for the presence of HT was neither sensitive nor specific. Increasing physicians' awareness on this issue and current recommendations should limit prescriptions of HT tests while providing the best possible care for patients with VTE.

Long-term Impact of Bariatric Surgery on Venous Thromboembolic Risk: A Matched Cohort Study

OBJECTIVE

The aim of this study is to evaluate the effect of bariatric surgery on long-term risk of VTEs in a large cohort of patients with obesity.

BACKGROUND

Obesity is a well-established risk factor for VTEs, such as pulmonary embolism and deep vein thrombosis. The rising prevalence of obesity and its associated co-morbidities, including VTE, represent a growing public health issue.

METHODS

A nested, retrospective matched cohort study was designed and conducted on prospectively collected national electronic healthcare records data from the Clinical Practice Research Datalink. Eight thousand, one hundred twelve patients were included in the study: the 4056 patients on the database who had undergone bariatric surgery, and equal numbers of age, sex, and body mass index matched controls. The primary endpoint was the occurrence of VTEs; secondary endpoints were the occurrence of deep vein thrombosis alone, pulmonary embolism alone.

RESULTS

Patients were followed up for a median of 10.7 years. The bariatric surgery cohort had a significantly lower occurrence of the primary outcome [hazard ratio (HR) 0.601; 95% confidence interval (CI) 0.430-0.841, P = 0.003]; mainly driven by a reduction in deep vein thrombosis (HR 0.523; 95% CI 0.349-0.783, P = 0·002) and not in pulmonary embolism (HR 0.882; 95% CI 0.511-1.521, P = 0.651).

CONCLUSIONS

The results of this nation-wide study set out to characterize the impact of bariatric surgery on long-term risk of thromboembolic events outline a significant reduction in thromboembolic events, driven by a reduction in deep vein thrombosis.

Prediction of recurrent venous thrombosis in all patients with a first venous thrombotic event: The Leiden Thrombosis Recurrence Risk Prediction model (L-TRRiP)

BACKGROUND

Recurrent venous thromboembolism (VTE) is common. Current guidelines suggest that patients with unprovoked VTE should continue anticoagulants unless they have a high bleeding risk, whereas all others can stop. Prediction models may refine this dichotomous distinction, but existing models apply only to patients with unprovoked first thrombosis. We aimed to develop a prediction model for all patients with first VTE, either provoked or unprovoked.

METHODS AND FINDINGS

Data were used from two population-based cohorts of patients with first VTE from the Netherlands (Multiple Environment and Genetic Assessment of Risk Factors for Venous Thrombosis [MEGA] follow-up study, performed from 1994 to 2009; model derivation; n = 3,750) and from Norway (Tromsø study, performed from 1999 to 2016; model validation; n = 663). Four versions of a VTE prediction model were developed: model A (clinical, laboratory, and genetic variables), model B (clinical variables and fewer laboratory markers), model C (clinical and genetic factors), and model D (clinical variables only). The outcome measure was recurrent VTE. To determine the discriminatory power, Harrell's C-statistic was calculated. A prognostic score was assessed for each patient. Kaplan-Meier plots for the observed recurrence risks were created in quintiles of the prognostic scores. For each patient, the 2-year predicted recurrence risk was calculated. Models C and D were validated in the Tromsø study. During 19,201 person-years of follow-up (median duration 5.7 years) in the MEGA study, 507 recurrences occurred. Model A had the highest predictive capability, with a C-statistic of 0.73 (95% CI 0.71-0.76). The discriminative performance was somewhat lower in the other models, with C-statistics of 0.72 for model B, 0.70 for model C, and 0.69 for model D. Internal validation showed a minimal degree of optimism bias. Models C and D were externally validated, with C-statistics of 0.64 (95% CI 0.62-0.66) and 0.65 (95% CI 0.63-0.66), respectively. According to model C, in 2,592 patients with provoked first events, 367 (15%) patients had a predicted 2-year risk of >10%, whereas in 1,082 patients whose first event was unprovoked, 484 (45%) had a predicted 2-year risk of <10%. A limitation of both cohorts is that laboratory measurements were missing in a substantial proportion of patients, which therefore were imputed.

CONCLUSIONS

The prediction model we propose applies to patients with provoked or unprovoked first VTE-except for patients with (a history of) cancer-allows refined risk stratification, and is easily usable. For optimal individualized treatment, a management study in which bleeding risks are also taken into account is necessary.

Long term prognosis of acute pulmonary embolism

BACKGROUND

Acute pulmonary embolism (PE) can be fatal if left untreated. Long-term prognosis of acute PE in the 21st century has not been fully reported. We aimed to determine the long-term prognosis of patients hospitalized with acute PE and compare survivalof patients with idiopathic and secondary PE.

MATERIALS AND METHODS

We retrospectively analysed a cohort of hospitalized patients with acute PE between 2006 and 2013.

EXCLUSION CRITERIA

<18 years, venous embolism of non-pulmonary veins, chronic thromboembolic pulmonary hypertension, and presumptive diagnosis without image confirmation. Only patients with a first PE episode were included. End-point: all-cause mortality. Patients were compared according to PE aetiology: idiopathic, secondary to neoplastic conditions and secondary to non-neoplastic conditions. A Cox-regression analysis was used to study the prognostic impact of PE aetiology.

RESULTS

We studied 872 hospitalized acute PE patients. Median age 70 years, 56.9% were women. PE was idiopathic in 376 (43.1%), secondary to a neoplastic condition in 284 (32.6%) and secondary to a condition other than neoplasia in 212 (24.3%). Patients were followed for a median 25 months period and 508 (58.3%) died. Patients with PE attributed to a neoplastic condition had the worst survival. Patients with idiopathic PE had a multivariate-adjusted HR of mortality of 1.46 (1.08-1.99) during the over 2-year follow-up period when compared to those with acute PE attributed to a non-neoplastic condition.

CONCLUSIONS

Patients with idiopathic acute PE have an almost 50% higher death risk in a median 2-year follow-up period than those with acute PE secondary to a condition other than neoplasia.

[Contemporary approaches to determine the duration of anticoagulant therapy for venous thromboembolism]

The review is devoted to the issue of optimal duration of anticoagulant therapy for venous thromboembolic complications (VTEC) using oral anticoagulants (OAC). These drugs are characterized by higher safety in comparison with vitamin K antagonists and make it possible to increase the duration of treatment for not only spontaneous thrombosis (with high risk of recurrence), but also thrombosis provoked by minor persistent and transient risk factors of VTEC. Efficacy and safety of prolonged treatment of VTEC using OAC was analyzed. Different classifications of primary thrombotic episode depending on risk of subsequent recurrence are presented. Moreover, scales for individual assessment of risk of recurrent thrombosis after anticoagulant therapy cancellation and risk of bleeding in case of continued treatment are given. Outcomes of long-term administration of rivaroxaban for VTEC are analyzed. It was concluded that OAC are safe for prolonged management of primary thrombotic episode. However, overall duration of treatment should be determined considering individual balance of benefits and risks.

D-dimer value in the diagnosis of pulmonary embolism-may it exclude only?

Background

Pulmonary embolism (PE) is the third most common cause of death for cardiovascular diseases in Europe. Quick PE diagnosis is therefore crucial for prognosis improvement. It is critical to have suitable screening tests both to exclude PE as well to select patient with highest likelihood of PE occurrence. Currently D-dimer test is accepted as important tool useful to exclude PE in low risk patients. Our goal was to assess the D-dimer test positive prognostic value.

Methods

A retrospective study based on medical record analysis of consecutively admitted patients to 9 wards of The University Clinical Center in Katowice who were hospitalized during four consecutive years was performed. Three hundred and seventy patients met the inclusion criteria for the study, which involved the D-dimer tests and computed tomographic pulmonary angiography (CTPA) performed during hospitalization. Assessed patients were divided into two groups: PE confirmed and PE excluded by CTPA.

Results

We have found that patients with D-dimer levels higher than 2,152 ng/mL had significantly increased risk of PE [area under curve (AUC) of 0.69; 95% CI, 0.64-0.75; P<0.05]. Positive predictive value (PPV) reached the level of 53%, whereas negative predictive value (NPV) reached 82%. We also found that patients with the history of neoplasm and at >65 years of age had D-dimer cut-off point moved to the level of 2,652 ng/mL (AUC of 0.67; 95% CI, 0.52-0.81; P<0.05).

Conclusions

Whereas the NPV of the D-dimer test is generally accepted our results suggest that, in selected cases, an increased plasmatic D-dimer levels may have PPV in PE diagnosis. Patients with the history of neoplasm have higher cut-off D-dimer points above which we should consider increased PE likelihood. CTPA should be considered even for patients with low probability of PE when D-dimer values exceed four times the normal level.

Anticoagulation quality and clinical outcomes in multimorbid elderly patients with acute venous thromboembolism

BACKGROUND

Multimorbid patients with acute venous thromboembolism (VTE) are often excluded from clinical trials and little is known about their prognosis.

OBJECTIVES

To examine whether multimorbidity is associated with adverse clinical outcomes and lower anticoagulation quality in older patients with VTE.

PATIENTS/METHODS

We studied 991 patients aged ≥65 years with acute VTE in a Swiss prospective multicenter cohort study. A modified Charlson Comorbidity Index was used to measure multimorbidity, which was defined as the presence ≥2 of 17 predefined comorbid conditions. We examined the association between multimorbidity and recurrent VTE and major bleeding, adjusting for confounders and periods of anticoagulation. We assessed whether the percentage of time spent in the therapeutic international normalized ratio (INR) range varied by the number of comorbidities present.

RESULTS

Overall, 708 (71%) patients were multimorbid. Multimorbid patients had a higher 3-year cumulative incidence of recurrent VTE (16.8 vs. 10.8%; P = 0.056) and major bleeding (18.7 vs. 9.0%; P = 0.001) than non-multimorbid patients. After adjustment, multimorbid patients had a significantly higher risk of recurrent VTE (sub-hazard ratio [SHR] 1.66, 95% confidence interval [CI] 1.08-2.57) and a higher risk of major bleeding (SHR 1.55, 95% CI 0.96-2.50), although the latter failed to achieve statistical significance. With increasing numbers of comorbid conditions, patients spent less time in and more time above and below the therapeutic INR range.

CONCLUSIONS

Multimorbid patients with acute VTE have not only a lower anticoagulation quality but also more complications. Clinical trials should explicitly enroll multimorbid patients to determine the optimal anticoagulation strategy in such patients.

Duration of anticoagulant therapy and VTE recurrence in patients with cancer

Purpose

Anticoagulant therapy for at least 3–6 months is currently recommended for treatment of venous thromboembolism (VTE) in patients with cancer, but the optimal duration of treatment is unknown. This study examines the association between the duration of anticoagulation treatment and VTE recurrence in cancer patients.

Methods

The Humana claims database was used to identify newly diagnosed cancer patients who had their first VTE diagnosis between January 1, 2013, and May 31, 2015, and initiated injectable or oral anticoagulant therapy. Follow-up was calculated from the index treatment initiation to the end of eligibility or end of data (June 2015). VTE recurrence was defined as a hospitalization with a primary diagnosis of VTE. Cox proportional hazards models were used to evaluate the risk of VTE recurrence by duration of therapy in patients who discontinued therapy.

Results

The study included 1158 patients. Compared to patients treated for 0 to 3 months, VTE recurrences were significantly lower among patients treated for 3 to 6, or over 6 months. After adjustment for baseline characteristics, patients treated for 3 to 6 months (HR [95%CI], 0.53; 0.37–0.76) and more than 6 months (HR [95%CI], 0.48; 0.34–0.68) were still significantly less likely to have VTE recurrences compared to patients treated for 0 to 3 months (both p < 0.01). Findings were similar using a VTE event definition that included outpatient visits.

Conclusions

Among newly diagnosed cancer patients with VTE, anticoagulant therapy lasting more than 3 months was associated with a lower risk of VTE recurrence.

Electronic supplementary material

The online version of this article (10.1007/s00520-019-4661-3) contains supplementary material, which is available to authorized users.

Clinical Phenotype of a First Unprovoked Acute Pulmonary Embolism Associated with Antiphospholipid Antibody Syndrome

BACKGROUND

Antiphospholipid antibody syndrome (APS), an important cause of acquired thrombophilia, is diagnosed when vascular thrombosis or pregnancy morbidity occurs with persistently positive antiphospholipid antibodies (aPL). APS is a risk factor for unprovoked recurrence of pulmonary embolism (PE). Performing laboratory testing for aPL after a first unprovoked acute PE is controversial. We investigated if a specific phenotype existed in patients with unprovoked with acute PE, suggesting the need to evaluate them for APS.

METHODS

We retrospectively reviewed patients with PE and APS (n=24) and those with unprovoked PE with aPL negative (n=44), evaluated 2006-2016 at the Asan Medical Center. We compared patient demographics, clinical manifestations, laboratory findings, and radiological findings between the groups.

RESULTS

On multivariate logistic regression analysis, two models of independent risk factors for APS-PE were suggested. Model I included hemoptysis (odds ratio [OR], 12.897; 95% confidence interval [CI], 1.025-162.343), low PE severity index (OR, 0.948; 95% CI, 0.917-0.979), and activated partial thromboplastin time (aPTT; OR, 1.166; 95% CI, 1.040-1.307). Model II included age (OR, 0.930; 95% CI, 0.893-0.969) and aPTT (OR, 1.104; 95% CI, 1.000-1.217).

CONCLUSION

We conclude that patients with first unprovoked PE with hemoptysis and are age <40; have a low pulmonary embolism severity index, especially in risk class I-II; and/or prolonged aPTT (above 75th percentile of the reference interval), should be suspected of having APS, and undergo laboratory testing for aPL.

APC-resistance as a possible predictor of recurrent thrombosis in women with Factor V Leiden

Hypothesis/aims of study. The current analysis was undertaken to elucidate the role of Factor Va resistance to proteolytic cleavage by activated protein C in FVL(1691)GA female carriers in the development of acute and recurrent thromboses. Study design, materials and methods. A prospective clinical cohort study of 1100 women of reproductive age was conducted, with the course and outcomes of 2,707 pregnancies analyzed. Two cohorts were specified: the main group consisted of 500 patients with FV(1691)GA genotype, and the control group consisted of 600 patients with FVL(1691)GG genotype. Results. FVL(1691)GA genotype was significantly associated with the development of venous thromboembolic complications (VTEC) compared to FVL(1691)GG genotype (OR 9.3; p < 0.0001). Episodes of recurrent thrombosis during and outside of pregnancy were registered only in FVL(1691)GA patients (OR 5.7, p = 0.2). In all cases, at the time of the thrombotic event and during the period before the episode of acute or recurrent thrombosis, an APC resistance normalized ratio (NR) value was ≤ 0.49, with no episodes of VTEC registered with an APC resistance NR value ≥ 0.5. Conclusion. Venous thromboses occur under the condition of expressed APC resistance with underlying FVL(1691)GA carriage. The APC resistance index can serve as an objective biochemical marker to determine the feasibility of thromboprophylaxis within the framework of personalized medicine.

Effectiveness and safety of apixaban versus rivaroxaban for prevention of recurrent venous thromboembolism and adverse bleeding events in patients with venous thromboembolism: a retrospective population-based cohort analysis

BACKGROUND

Apixaban and rivaroxaban, both direct-acting oral anticoagulants, are being increasingly used in routine clinical practice because of their fixed dosing and favourable pharmacological profiles. Differences in the risk of recurrent venous thromboembolism and major bleeding events between the two drugs are currently unknown. We aimed to compare the effectiveness and safety of apixaban and rivaroxaban in prevention of recurrent venous thromboembolism and major bleeding events in patients with venous thromboembolism.

METHODS

We did a retrospective cohort analysis of data from the Truven Health MarketScan commercial and Medicare Supplement claims databases in the USA. We analysed data for adult patients with newly diagnosed venous thromboembolism (deep vein thrombosis or pulmonary embolism) who were new users of apixaban or rivaroxaban between Jan 1, 2014, and Dec 31, 2016. Patients who did not initiate the study drugs within 30 days of their diagnosis, those without 12 months of continuous enrolment in medical and pharmacy benefits, and those who used other anticoagulants during the baseline period were excluded. The primary effectiveness outcome was the incidence of recurrent venous thromboembolism and the primary safety outcome was the incidence of major bleeding events. Cox-proportional hazard models after propensity score matching were used to calculate the hazard ratio (HR) and 95% CI.

FINDINGS

After propensity score matching, 15 254 patients were included in the cohort (3091 apixaban users and 12 163 rivaroxaban users). The crude incidence of recurrent venous thromboembolism was three per 100 person-years in the apixaban group and seven per 100 person-years in the rivaroxaban group. The incidence of major bleeding was three per 100 person-years in the apixaban group and six per 100 person-years in the rivaroxaban group. In multivariable Cox regression models, the use of apixaban compared with rivaroxaban was associated with decreased risk of recurrent venous thromboembolism (HR 0·37 [95% CI 0·24-0·55]; p<0·0001) and major bleeding events (0·54 [0·37-0·82]; p=0·0031).

INTERPRETATION

Based on our findings, apixaban seems to be more effective than rivaroxaban in preventing the development of recurrent venous thromboembolism and major bleeding events. Our data might give some assurance to clinicians that apixaban can be an effective and safe therapeutic option for treatment of patients with venous thromboembolism.

FUNDING

None.

Impact of symptomatic atherosclerosis in patients with pulmonary embolism

BACKGROUND

Atherosclerosis is associated with increased cardiovascular mortality. Associations between venous thromboembolism and atherosclerosis were recently reported. We aimed to investigate the impact of symptomatic atherosclerosis on adverse outcomes in patients with pulmonary embolism (PE) and to identify significant differences among patients with PE stratified by symptomatic atherosclerosis.

METHODS

Patients were selected by screening the nationwide inpatients sample for PE (ICD-code I26) stratified by symptomatic atherosclerosis (composite of coronary artery disease [ICD-code I25], myocardial infarction [ICD-code I21], ischemic stroke [ICD-code I63], and/or atherosclerotic arterial diseases [ICD-code I70]). We compared PE patients with (PE + Athero) and without (PE - Athero) symptomatic atherosclerosis and analysed the impact of symptomatic atherosclerosis on adverse outcomes.

RESULTS

Overall, 213,995 patients with PE (54.2% females) were included in this analysis. Of these, 30,157 (14.1%) had symptomatic atherosclerosis with age-dependent incline. Deep vein thrombosis or thrombophlebitis (45.1% vs. 36.9%, P < 0.001) was more commonly observed in the PE - Athero group (Odds Ratio (OR) 0.713 [95% CI 0.695-0.731], P < 0.001). In-hospital mortality (12.1% vs. 9.6%, P < 0.001) and adverse in-hospital events (16.8% vs. 12.6%, P < 0.001) were affected by symptomatic atherosclerosis; both in-hospital mortality (OR 1.107 [95% CI 1.061-1.155], P < 0.001) and adverse in-hospital outcomes (OR 1.143 [95%CI 1.102-1.186], P < 0.001) were affected independently of age, gender, comorbidities, and reperfusion treatments.

CONCLUSIONS

Symptomatic atherosclerosis in patients with PE increased with age and was associated with a poorer outcome. Cardiovascular-atherosclerotic diseases might play a major role in thrombus formation in isolated PE.

Residual pulmonary vascular obstruction and recurrence after acute pulmonary embolism: protocol for a systematic review and meta-analysis of individual participant data

BACKGROUND

In patients with a first, unprovoked venous thromboembolism (VTE), the optimal duration of anticoagulant therapy (AT) is controversial due to tightly balanced risks and benefits of indefinite anticoagulation. The objective of this study is to assess among patients with a first acute pulmonary embolism (PE) who received ≥3 months of AT and thereafter had a planar lung scan, whether residual pulmonary vascular obstruction (RPVO) is associated with VTE recurrence after discontinuation of AT.

METHODS AND ANALYSIS

We will conduct a systematic review with a meta-analysis of individual participant data of contemporary studies evaluating the prognostic significance of RPVO in patients with a first acute PE. We will search from inception to 24 January 2018, PubMed, Medline, Embase and Cochrane's Central Registry for Randomized Controlled Trials, CENTRAL for randomized controlled trials and prospective cohort studies. Two reviewers will conduct all screening and data collection independently. The methodological quality and risk of bias of eligible studies will be carefully and rigorously assessed using the Risk Of Bias In Non-randomised Studies of Interventions tool. The primary objective will be to assess the relationship between RPVO on ventilation-perfusion scan after completion of at least 3 months of AT after an acute PE event, and the risk of an objectively confirmed symptomatic recurrent VTE (including deep vein thrombosis or PE) or death due to PE. The secondary objectives will include the assessment of the optimal RPVO cut-off and the risk of recurrent VTE, as well as the relationship between the relative change in RPVO between PE diagnosis and at discontinuation of AT (≥3 months) and risk of recurrent VTE.

ETHICS AND DISSEMINATION

This study of secondary data does not require ethics approval. It will be presented internationally and published in the peer-reviewed literature.

PROSPERO REGISTRATION NUMBER

CRD42017081080.

Cost comparison of continued anticoagulation with rivaroxaban versus placebo based on the 1-year EINSTEIN-Extension trial efficacy and safety results

AIMS

The EINSTEIN-Extension trial (EINSTEIN-EXT) found that continued treatment with rivaroxaban for an additional 6 or 12 months (vs placebo) after 6-12 months of initial anticoagulation significantly reduced the risk of recurrent venous thromboembolism (VTE) with a small non-significant increased risk of major bleeding (none fatal or in critical site). This study aimed to compare total healthcare cost between rivaroxaban and placebo, based on the EINSTEIN-EXT event rates.

METHODS

Total healthcare cost was calculated as the sum of treatment and clinical event costs from a US managed care perspective. Treatment duration and event rates were obtained from the EINSTEIN-EXT study. Adjustment on treatment duration was made by assuming a 10% non-adherence rate. Drug costs were based on wholesale acquisition costs. Cost estimates for clinical events (i.e. recurrent deep vein thrombosis [DVT], recurrent pulmonary embolism, major bleeding, clinically relevant non-major bleeding) were determined from the literature. Results were examined over a ±20% range of each cost component and over 95% confidence intervals (CIs) of event rate differences in deterministic (one-way) and probabilistic sensitivity analyses (PSA).

RESULTS

Total healthcare cost was $1,454 lower for rivaroxaban-treated (vs placebo-treated) patients in the base-case, with a lower clinical event cost fully offsetting drug cost. The cost savings of recurrent DVT alone (-$3,102) was greater than drug cost ($2,723). Total healthcare cost remained lower for rivaroxaban in the majority (73%) of PSA (cost difference [95% CI] = -$1,454 [-$2,396, $1,231]).

LIMITATIONS

This study was conducted over the 1-year observation period of the EINSTEIN-EXT trial, which limited "real-world" applicability and examination of long-term economic impact. Assumptions on drug and clinical event costs were US-based and, thus, not applicable to other healthcare systems.

CONCLUSIONS

Total healthcare costs were estimated to be lower for patients continuing rivaroxaban therapy compared to those receiving placebo in VTE patients who had completed 6-12 months of VTE treatment.

Non-vitamin K antagonist oral anticoagulants for pulmonary embolism: who, where and for how long?

INTRODUCTION

Acute pulmonary embolism (PE) is a relatively common cardiopulmonary emergency that is a major cause of hospitalization and morbidity and is the primary cause of mortality associated with venous thromboembolism (VTE). During the last decade, one of the biggest changes in the management of PE has been the approval of four non-vitamin K antagonist oral anticoagulants (NOACs; apixaban, dabigatran, edoxaban and rivaroxaban) for the treatment of PE and deep vein thrombosis and secondary prevention of VTE. Areas covered: This article reviews the evolving management of PE in the NOAC era and addresses three fundamental questions: who should receive NOACs over conventional heparin/vitamin K antagonist regimens for the treatment of acute PE; should patients be treated as inpatients or outpatients; and how long should patients be treated to reduce the risk of recurrence? Expert commentary: The management of PE is changing. NOACs provide new anticoagulant treatment options for patients with PE, based on Phase III clinical study results. The consistent efficacy and safety profile of NOACs across many PE patient subgroups, including the elderly, fragile patients, those with active cancer and high-risk (right ventricular dysfunction) patients, suggests NOAC use will increase among these patients.

Association between TLR9 rs5743836 polymorphism and risk of recurrent venous thromboembolism

Recent gene knockout studies on mice have shown the role of toll-like receptor 9 (TLR9) in resolution of venous thromboembolism (VTE) through sterile inflammation. However, the role of a putative functional TLR9 polymorphism (rs5743836) in risk assessment of VTE recurrence remains unknown. The aim of our study was to investigate the TLR9 rs5743836 polymorphism in VTE patients and its association with the risk of VTE recurrence. We analyzed TLR9 rs5743836 polymorphism in Malmö thrombophilia study patients; a prospective follow-up study of 1465 VTE patients by Taqman PCR. From a total of 1465 VTE patients, those who had VTE before inclusion and those who died or had VTE recurrence during anticoagulant treatment were excluded (n = 415). Cox regression analyses were performed on the remaining 1050 VTE patients, including 126 (12.5%) patients that had recurrent VTE during follow-up period. TLR9 polymorphism was significantly associated with higher risk of VTE recurrence in female patients (HR 3.46, 95% CI 1.06–11.33) independent of acquired risk factors for VTE, family history, risk of thrombophilia and deep vein thrombosis (DVT) location. Similarly, in unprovoked VTE patients, TLR9 polymorphism was significantly associated with higher risk of VTE recurrence in female patients (HR 5.94, 95% CI 1.25–28.13) after adjusting for family history, risk of thrombophilia and DVT location. No association between TLR9 polymorphism and risk of VTE recurrence was found in male patients. Our results suggest that TLR9 rs5743836 polymorphism is an independent risk factor for VTE recurrence in female patients but not in males.

Clinical outcomes of prolonged anticoagulation with rivaroxaban after unprovoked venous thromboembolism

BACKGROUND

Randomized trial data demonstrate the gain of extended duration anticoagulation in patients with venous thromboembolic events (VTE); however, real-world data are limited.

OBJECTIVES

Assess the risk of recurrent VTE and major bleeding in a real-world setting of patients who experienced unprovoked VTE and received extended treatment with rivaroxaban.

METHODS

US claims databases (February 2011-April 2015) were used in this retrospective study. The study population included adult patients initiated on rivaroxaban within 7 days after their first unprovoked VTE (ie, deep vein thrombosis, pulmonary embolism) and received ≥3 months continuous rivaroxaban treatment (index date: end of 3-month treatment). Patients who were treated beyond 3 months formed the continued cohort and the remainder formed the discontinued cohort (ie, discontinued at 3 months). Adjusted Kaplan-Meier rates for recurrent VTE and major bleeding events were compared between cohorts with confounders being controlled through a propensity score weighting approach.

RESULTS

Patients in the continued cohort (N = 3763) had significantly lower rates of recurrent VTE than those who discontinued (N = 1051): 0.57% vs 1.19% (P = .042), 1.07% vs 2.10% (P = .017), and 1.45% vs 2.60% (P = .023) at 3, 6, and 12 months, respectively. No significant differences in the rate of major bleeding were observed between cohorts. A sensitivity analysis among unprovoked VTE patients receiving rivaroxaban for ≥6 months showed similar results.

CONCLUSIONS

Continued rivaroxaban treatment beyond an initial 3- or 6-month treatment period significantly lowered the risk of recurrent VTE without a significant increase of major bleeding, compared to treatment discontinued at 3 or 6 months.

The predictive value of markers of fibrinolysis and endothelial dysfunction in the post thrombotic syndrome

The post thrombotic syndrome (PTS) develops in 20–40% of deep venous thrombosis (DVT) patients. Risk factors for PTS have not been well elucidated. Identification of risk factors would facilitate individualised risk assessment for PTS. We conducted a systematic review to determine whether biomarkers of fibrinolysis or endothelial dysfunction can predict the risk for PTS among DVT patients. Studies were identified by searching the electronic databases PubMed, EMBASE, Scopus and Web of science. We included studies published between 1990 and 2013, measured biomarker levels in adult DVT patients, and reported rates of PTS development. Fourteen studies were included: 11 investigated the association between D-dimer and PTS; three examined fibrinogen; two measured von Willebrand factor; one measured plasminogen activator inhibitor-1; one assessed ADAMTS-13 (A Disintegrin and Metalloprotease with Thrombospondin type 1 repeats) and one measured factor XIII activity. Studies varied with regards to inclusion criteria, definition of PTS, time point and method of biomarker measurement. We were unable to meta-analyse results due to marked clinical heterogeneity. Descriptively, a significant association with PTS was found for D-dimer in four studies and factor XIII in one study. Further prospective research is needed to elucidate whether these markers might be useful to predict PTS development.

Optimal long-term pharmacological treatment of patients with venous thromboembolism that was unprovoked or associated with weak risk factors

INTRODUCTION

Unprovoked venous thromboembolism (VTE) tend to recur. Many factors, patient- or event-related, influence the individual risk of recurrence. After initial and long-term (usually for 3-6 months) anticoagulant therapy, extended anticoagulation has been recommended in patients at high risk of recurrence, provided they do not have a high risk of bleeding. Areas covered: The effect of different risk factors on the risk of recurrence is discussed, as well as risk factors for bleeding. The estimation of individual balance between these two risks is crucial to decide which can be the best treatment duration in single patients. The use of direct oral anticoagulants, with likely less risk of bleeding, may influence the balance. D-dimer assessment during and after anticoagulation is stopped is also commented for its role to help identifying the individual risk of recurrence. Expert commentary: All patients with a first VTE should be reconsidered after the initial 3-6 months of treatment. Anticoagulation can then be stopped or continued in relation to low or very high risk of recurrence, respectively. Serial D-dimer assessment during the first 2 or 3 months after anticoagulation is stopped is useful in patients with uncertain risk evaluation (especially after unprovoked events).

Optical sensing of anticoagulation status: Towards point-of-care coagulation testing

Anticoagulant overdose is associated with major bleeding complications. Rapid coagulation sensing may ensure safe and accurate anticoagulant dosing and reduce bleeding risk. Here, we report the novel use of Laser Speckle Rheology (LSR) for measuring anticoagulation and haemodilution status in whole blood. In the LSR approach, blood from 12 patients and 4 swine was placed in disposable cartridges and time-varying intensity fluctuations of laser speckle patterns were measured to quantify the viscoelastic modulus during clotting. Coagulation parameters, mainly clotting time, clot progression rate (α-angle) and maximum clot stiffness (MA) were derived from the clot viscoelasticity trace and compared with standard Thromboelastography (TEG). To demonstrate the capability for anticoagulation sensing in patients, blood samples from 12 patients treated with warfarin anticoagulant were analyzed. LSR clotting time correlated with prothrombin and activated partial thromboplastin time (r = 0.57-0.77, p<0.04) and all LSR parameters demonstrated good correlation with TEG (r = 0.61-0.87, p<0.04). To further evaluate the dose-dependent sensitivity of LSR parameters, swine blood was spiked with varying concentrations of heparin, argatroban and rivaroxaban or serially diluted with saline. We observed that anticoagulant treatments prolonged LSR clotting time in a dose-dependent manner that correlated closely with TEG (r = 0.99, p<0.01). LSR angle was unaltered by anticoagulation whereas TEG angle presented dose-dependent diminution likely linked to the mechanical manipulation of the clot. In both LSR and TEG, MA was largely unaffected by anticoagulation, and LSR presented a higher sensitivity to increased haemodilution in comparison to TEG (p<0.01). Our results establish that LSR rapidly and accurately measures the response of various anticoagulants, opening the opportunity for routine anticoagulation monitoring at the point-of-care or for patient self-testing.