Long-Term Management of Patients After Venous Thromboembolism

Warfarin Failure in a Patient With Chronic Thromboembolic Pulmonary Hypertension: A Case Report and Literature Review

Chronic thromboembolic pulmonary hypertension (CTEPH) is a form of pulmonary hypertension caused by chronic venous thromboembolism (VTE). Venous thromboembolism (VTE) manifests as deep vein thrombosis (DVT), progressing to pulmonary embolism (PE). Pulmonary endarterectomy (PEA) is the preferred therapeutic option as it provides vascular disobliteration. Long-term anticoagulation with warfarin or direct oral anticoagulants (DOACs) is recommended for patients at risk for recurrent DVT in poor surgical candidates. However, treatment failure remains a concern. We present a patient who had VTE despite long-term anticoagulation with warfarin who had failed treatment and developed VTE with a therapeutic dilemma to continue anticoagulation despite supratherapeutic international normalized ratio (INR).

Clinical characteristics, time course, and outcomes of major bleeding according to bleeding site in patients with venous thromboembolism

BACKGROUND

Bleeding is the most dreaded complication of anticoagulant therapy for acute venous thromboembolism (VTE). Limited data exist about patient characteristics, time course and outcomes of major bleeding, according to the bleeding site.

METHODS

We used the data from the Registro Informatizado Enfermedad TromboEmbólica (RIETE) registry (03/2001-07/2018) and identified patients who suffered from major bleeding during anticoagulation. We assessed patient characteristics, time course, and 30-day outcomes including mortality, re-bleeding, and VTE recurrences, according to bleeding site.

RESULTS

Among 78,136 patients with VTE receiving anticoagulation, 2244 (2.9%) suffered from major bleeding (gastrointestinal in 800, intracranial in 417, hematoma in 410, genitourinary in 222, retroperitoneal in 145; other sites in 250). There were variations in baseline characteristics, including older age (P < 0.001) and predominance of women (70.2% [95% confidence interval [CI]]: 65.6-74.6% versus 50.5%, 95% CI: 48.2-52.9, P < 0.001) in patients with hematoma, compared with other patients. Overall, 82.7% of hematomas and 81.4% of retroperitoneal bleeds occurred in the first 90 days after the diagnosis of the VTE event, compared with only 50.6% of intracranial bleeds. Across the bleeding subgroups, 30-day all-cause mortality rates were highest in patients who suffered from intracranial bleeding (41.0%; 99% confidence interval [CI]: 34.8-47.4%), and lowest in patients who suffered from hematoma (17.8%; 99% CI: 13.2-23.2%). Patients who suffered from a major bleeding event in the first 30 days after VTE had significantly higher odds at 90-day follow-up to develop mortality (including from bleeding), recurrent VTE, and recurrent major bleeding (all Ps < 0.001). Variations were observed in the results according to the bleeding site.

CONCLUSIONS

Major bleeding is a serious complication in VTE patients. Patient characteristics, time course and outcomes varied substantially according to the bleeding site. Additional studies are needed to tease out the impact of patient risk factors, treatment regimens, and a potential distinct effect from the site of bleeding.

TRIAL REGISTRATION

https://clinicaltrials.gov/ct2/show/NCT02832245 (RIETE registry).

Thrombophilia screening revisited: an issue of personalized medicine

Clinical thrombophilia is the consequence of multiple gene and/or environment interactions. Thrombophilia screening requires a targeted patient with specific indication, in which a finding would have implications. Carrying out a thrombophilia examination in the physician's practice is often a cause of uncertainty and concern. The concerns begin in choosing the right patient to be examined, are associated with the time of investigation, with the choice of analysis, the test-material and with the correct interpretation of the results. Difficulties, which can influence the results, can occur with both organization and blood sampling. As common for any analysis, pre-analytical, analytical and post-analytical factors should be considered, as well as the possibility of false positive or false negative results. Finally, recommendation of correct therapeutic and prophylactic measures for the patient and his relatives is an additional focus. In this article we want to provide-on the basis of the evidence and personal experience-the theory of thrombophilia-investigation, the indications for testing, as well as practical recommendations for treatment options.

Depletion of CD4 and CD8 Positive T Cells Impairs Venous Thrombus Resolution in Mice

Resolution of deep venous thrombosis involves coordinated inflammatory processes. T cells regulate inflammation in vivo and modulate vascular remodeling in other settings, but their role in venous thrombus resolution remains undefined. To determine the role of T cells in venous thrombus resolution in vivo, stasis induced thrombi were created by vena cava ligation in outbred CD-1 mice. CD4 and CD8 positive T cells, as determined by flow cytometry, were present in thrombi both during thrombus formation and resolution. Depletion of the CD4 and CD8 positive T cells by antibody treatment selectively impaired thrombus resolution compared to animals treated with isotype control antibodies, without an effect on venous thrombus formation. Quantitation of intra-thrombus macrophage numbers, fibrinolytic marker expression, and gelatinolytic activity by zymography revealed that T cell depletion decreased the number of macrophages, reduced the expression of fibrinolytic marker urokinase plasminogen activator (uPA), and decreased the activity of matrix metalloprotinease-9 (MMP-9). These data implicate CD4 and CD8 positive T cells in functionally contributing to venous thrombus resolution, thus representing a potential therapeutic target, but also underscoring potential risks involved in T cell depletion used clinically for solid organ and hematopoietic transplantation procedures.

Vena cava filters in patients presenting with major bleeding during anticoagulation for venous thromboembolism

The association between inferior vena cava filter (IVC) use and outcome in patients presenting with major bleeding during anticoagulation for venous thromboembolism (VTE) has not been thoroughly investigated. We used the RIETE registry to compare the 30-day outcomes (death, major re-bleeding or VTE recurrences) in VTE patients who bled during the first 3 months of therapy, regarding the insertion of an IVC filter. A propensity score matched (PSM) analysis was performed to adjust for potential confounders. From January 2001 to September 2016, 1065 VTE patients had major bleeding during the first 3 months of anticoagulation (gastrointestinal 370; intracranial 124). Of these, 122 patients (11%) received an IVC filter. Patients receiving a filter restarted anticoagulation later (median, 4 vs. 2 days) and at lower doses (95 ± 52 IU/kg/day vs. 104 ± 55 of low-molecular-weight heparin) than those not receiving a filter. During the first 30 days after bleeding (after excluding 246 patients who died within the first 24 h), 283 patients (27%) died, 63 (5.9%) had non-fatal re-bleeding and 19 (1.8%) had recurrent pulmonary embolism (PE). In PSM analysis, patients receiving an IVC filter (n = 122) had a lower risk for all-cause death (HR 0.49; 95% CI 0.31-0.77) or fatal bleeding (HR 0.16; 95% CI 0.07-0.49) and a similar risk for re-bleeding (HR 0.55; 95% CI 0.23-1.40) or PE recurrences (HR 1.57; 95% CI 0.38-6.36) than those not receiving a filter (n = 429). In VTE patients experiencing major bleeding during the first 3 months, use of an IVC filter was associated with reduced mortality rates.Clinical Trial Registration NCT02832245.

Comparison of prediction value of four bleeding risk scores for pulmonary embolism with anticoagulation: A real-world study in Chinese patients

BACKGROUND

Major bleeding (MB) and clinically relevant bleeding (CRB) are the most common seen complications associated with anticoagulation treatment for pulmonary embolism (PE) patients. A bleeding risk score (BRS) may help to accurately determine the risk of bleeding and make better decisions for patients in clinical practice.

METHODS

Patients diagnosed as acute PE and who met the inclusion criteria in Beijing Chao-Yang Hospital from January 2009 to September 2013 were consecutively enrolled. Baseline data were collected. Four BRS (Kuijer score, RIETE score, Kearon score and Nieuwenhuis score) were assessed and compared using the area under the receiver operating characteristic curve (AUC).

RESULTS

A total number of 563 patients were included in the study. Of which, 16 had MB and 89 had CRB within three months of anticoagulation treatment. Three months' cumulative incidence for MB and CRB events was 0.03 (95% CI 0.01-0.05) and 0.17 (95% CI 0.12-0.21), respectively. In our study population, the AUCs for Kuijer, RIETE, Kearon and Nieuwenhuis scores were 0.57 (95% CI 0.44~0.68), 0.56 (95% CI 0.45-0.71), 0.75 (95% CI 0.60~0.89) and 0.59 (95% CI 0.41~0.74), respectively. In addition, the AUCs of four BRS for CRB were all poor, with values less than 0.65.

CONCLUSIONS

Only the Kearon score appeared to have more accuracy in predicting the risk of MB. Further large prospective studies are needed to externally validate a BRS for CRB.

Management and outcome of major bleeding in patients receiving vitamin K antagonists for venous thromboembolism

BACKGROUND

The optimal management of major bleeding in patients receiving vitamin K antagonists (VKA) for venous thromboembolism (VTE) is unclear.

METHODS

We used the RIETE (Registro Informatizado Enfermedad TromboEmbólica) registry to assess the management and 30-day outcomes after major bleeding in patients receiving VKA for VTE.

RESULTS

From January 2013 to December 2017, 267 of 18,416 patients (1.4%) receiving long-term VKA for VTE had a major bleeding (in the gastrointestinal tract 78, intracranial 72, hematoma 50, genitourinary 20, other 47). Overall, 151 patients (57%) received blood transfusion; 110 (41%) vitamin K; 37 (14%) fresh frozen plasma; 29 (11%) pro-haemostatic agents and 20 (7.5%) a vena cava filter. During the first 30 days, 59 patients (22%) died (41 died of bleeding) and 13 (4.9%) had a thrombosis. On multivariable analysis, patients with intracranial bleeding (hazard ratio [HR]: 4.58; 95%CI: 2.40-8.72) and those with renal insufficiency at baseline (HR: 2.73; 95%CI: 1.45-5.15) had an increased mortality risk, whereas those receiving vitamin K had a lower risk (HR: 0.47; 0.24-0.92). On the other hand, patients receiving fresh frozen plasma were at increased risk for thrombotic events (HR: 4.22; 95%CI: 1.25-14.3).

CONCLUSIONS

Major bleeding in VTE patients receiving VKA carries a high mortality rate. Intracranial bleeding and renal insufficiency increased the risk. Fresh frozen plasma seems to increase this risk for recurrent VTE.

Delayed retroperitoneal arterial hemorrhage after inferior vena cava filter deployment: A case report

RATIONALE

Pulmonary embolization is a life-threatening condition. The deployment of inferior vena cava (IVC) filter is the first choice for preventing embolus from the lower extremity. However, IVC filter complications are rare but not to be neglected. Penetration of the arterial wall may result in catastrophic damages. This case report describes a woman who suffered from retroperitoneal hemorrhage after placement of an IVC filter due to a pulmonary embolization. Her filter was found to have penetrated the right lumbar artery and caused the massive bleeding. She was successfully treated with endovascular coil embolization.

PATIENT CONCERNS

A 47-year old woman presenting with pulmonary embolization was admitted to our hospital. An IVC filter was deployed. Twenty days after her operation, she suffered from an intolerable lumbago when bending over. Contrast-enhanced computed tomography at the local hospital showed a massive retroperitoneal hematoma adjacent to the IVC filter.

DIAGNOSES

Contrast-enhanced CT at the local hospital showed a massive retroperitoneal hematoma adjacent to the IVC filter. Thereafter, she was transferred to our hospital. Her hemoglobin and INR were 7.1 g/dl and 3.4, respectively. Her systolic blood pressure decreased to 70 mmHg with heart rate increasing to 110 beats/min. The shock index was greater than 1.5.

INTERVENTIONS

Angiography of the abdominal aorta showed extravasation of contrast medium from the right third lumbar artery. Embolization of the lumbar arteries was performed with coils.

OUTCOMES

Several days later, she recovered with hematoma shrinking in size and was discharged from the hospital with stable condition.

LESSONS

It highlights that appropriate monitoring of patients with IVC filters is an essential part during the long-term management. Endovascular treatment showed a safe and effective way to treat arterial perforation caused by hooks of inferior vena cava filters.

A 6-Year Epidemiological Study of Pulmonary Embolism in an Emergency Department

Objective

To identify the epidemiology and early clinical features of patients with pulmonary embolism with a view to facilitate making the correct diagnosis.

Methodology

A retrospective study of patients admitted through the emergency department with a discharge diagnosis of pulmonary embolism in the computerised Clinical Management System from 1st January 1999 to 31st December 2004 in a public emergency general hospital in Hong Kong.

Results

Twenty-two patients were newly diagnosed to have pulmonary embolism and included in the study. The patients' clinical features and investigation findings were analysed. Old age and immobilisation were the most common risk factors identified. Nine patients were found to have deep vein thrombosis but none of them complained of calf pain during consultation in the emergency department. Most patients had symptoms of shortness of breath and chest pain on presentation. Fourteen patients had type 1 respiratory failure. The electrocardiogram and chest X-ray findings were non-specific. All the patients with D-dimer done showed positive results. CT scans were used in all patients to make the final diagnosis. Nineteen patients received low molecular weight heparin followed by warfarin and three patients had thrombolytic therapy.

Conclusion

Pulmonary embolism is not a commonly diagnosed disease in Hong Kong. The symptoms are non-specific and it is difficult to make the correct diagnosis in the emergency department.

D-dimer for prediction of long-term outcome in cryptogenic stroke patients with patent foramen ovale

Patent foramen ovale (PFO) is a potential cause of cryptogenic stroke, given the possibility of paradoxical embolism from venous to systemic circulation. D-dimer level is used to screen venous thrombosis. We investigated the risk of embolism and mortality according to the presence of PFO and D-dimer levels in cryptogenic stroke patients. A total of 570 first-ever cryptogenic stroke patients who underwent transesophageal echocardiography were included in this study. D-dimer was assessed using latex agglutination assay during admission. The association of long-term outcomes with the presence of PFO and D-dimer levels was investigated. PFO was detected in 241 patients (42.3 %). During a mean 34.0 ± 22.8 months of follow-up, all-cause death occurred in 58 (10.2 %) patients, ischaemic stroke in 33 (5.8 %), and pulmonary thromboembolism in 6 (1.1 %). Multivariate Cox regression analysis showed that a D-dimer level of > 1,000 ng/ml was an independent predictor for recurrent ischaemic stroke in patients with PFO (hazard ratio 5.341, 95 % confidence interval 1.648–17.309, p=0.005), but not in those without PFO. However, in patients without PFO, a D-dimer level of > 1,000 ng/ml was independently related with all-cause mortality. The risk of pulmonary thromboembolism tended to be high in patients with high D-dimer levels, regardless of PFO. Elevated D-dimer levels in cryptogenic stroke were predictive of the long-term outcome, which differed according to the presence of PFO. The coexistence of PFO and a high D-dimer level increased the risk of recurrent ischaemic stroke. The D-dimer test in cryptogenic stroke patients may be useful for predicting outcomes and deciding treatment strategy.

Long-Term Effects of Unprovoked Venous Thromboembolism on Mortality and Major Cardiovascular Events

Background

Patients with unprovoked venous thromboembolism (VTE) are at an increased risk of mortality, but whether their cardiovascular risks also increase remains to be determined. We aimed to investigate the factors associated with overall mortality and major adverse cardiovascular events in patients with unprovoked VTE.

Methods and Results

We identified 2154 patients newly diagnosed with unprovoked VTE from Taiwan's National Health Insurance Database between 2000 and 2013, excluding those with reversible etiologies, underlying cancer, or autoimmune diseases. These patients with VTE were compared with an age‐, sex‐, and cardiovascular risk‐matched cohort of 4308 controls. The risk of mortality and major adverse cardiovascular events in patients with VTE was 2.23 (CI, 1.93–2.57; P<0.0001) and 1.86 (CI, 1.65–2.09; P<0.0001) times, respectively, higher than that of the conditions in controls. These events mostly occurred during the first year after the diagnosis of unprovoked VTE. Among patients with VTE, advanced age, male sex, and comorbid diabetes mellitus indicated a higher incidence of mortality and major adverse cardiovascular events. Conversely, comorbid hyperlipidemia attenuated these risks.

Conclusions

This nation‐wide cohort study revealed that patients with unprovoked VTE, particularly older males with diabetes mellitus, had an elevated risk of both mortality and cardiovascular events. Risk of mortality and major adverse cardiovascular events were highest within the first year after diagnosis and persisted during the 10 years of follow‐up.

Myeloid p53 regulates macrophage polarization and venous thrombus resolution by inflammatory vascular remodeling in mice

Deep venous thrombosis (DVT) remains a common and serious cardiovascular problem with both fatal and long-term consequences. The consequences of DVT include the development of postthrombotic syndrome in 25% to 60% of DVT patients. Despite the clinical importance of venous thrombus resolution, the cellular and molecular mediators involved are poorly understood, and currently there is no molecular therapy to accelerate this process. Several lines of evidence suggest that a complex and interrelated array of molecular signaling processes are involved in the inflammatory vascular remodeling associated with the resolution of DVT. Here, we have identified a role for the tumor suppressor gene p53 in regulating venous thrombus resolution. Using the stasis model of venous thrombosis and resolution in mice, we found that genetic deficiency of p53 or pharmacologic inhibition by pifithrin impairs thrombus resolution and is associated with increased fibrosis and altered expression of matrix metalloproteinase-2. The effect of p53 loss was mediated by cells of the myeloid lineage, resulting in enhanced polarization of the cytokine milieu toward an M1-like phenotype. Furthermore, augmentation of p53 activity using the pharmacological agonist of p53, quinacrine, accelerates venous thrombus resolution in a p53-dependent manner, even after establishment of thrombosis. Together, these studies define mechanisms by which p53 regulates thrombus resolution by increasing inflammatory vascular remodeling of venous thrombi in vivo, and the potential therapeutic application of a p53 agonist as a treatment to accelerate this process in patients with DVT.

Hospital-related first venous thromboembolism and risk of recurrence

Essentials Recurrence risk after a hospital-related venous thromboembolism (VTE) is underinvestigated. We explored this association in a cohort of patients with a first VTE from the Tromsø study. Stratification on hospital-related factors revealed considerable differences in recurrence risk. The recurrence risk was high in cases with a VTE related to hospitalization for medical illness.

SUMMARY

Background Hospitalization is a well-established risk factor for first venous thromboembolism (VTE), but the risk of recurrence, particularly in patients hospitalized for conditions other than cancer or surgery, has scarcely been investigated. The cumulative incidence of recurrence in hospital-related VTE may be influenced by the competing risk of death. Objectives To investigate the risk of recurrence and mortality among patients with a first hospital-related VTE in models with and without death as a competing event. Methods Information on hospital-related risk factors was collected in 822 patients with a first-lifetime VTE derived from the Tromsø study. Recurrent VTEs and deaths were recorded during follow-up (1994-2012). Results During a median of 2.79 years of follow-up, 132 patients experienced a recurrent VTE. Stratification on hospital-related factors revealed considerable differences in recurrence risk. The 5-year cumulative incidence of recurrence was 27.4%, 11.0% and 20.1% in patients with incident VTEs related to cancer, surgery or other medical illness, respectively, and 18.4% in patients with a non-hospital-related first VTE. The mortality rates were high for all subgroups of hospital-related VTE, except for surgery-related events. Consequently, the cumulative incidence of recurrence dropped in the competing risk analyses, showing a 5-year cumulative incidence of 14.4%, 11.7% and 9.7% in patients with a first VTE related to hospitalization for other medical illness, cancer or surgery, respectively. Conclusions Our findings suggest that patients with incident VTEs related to hospitalization for medical illness other than cancer or surgery have a high recurrence-risk, even in the presence of competing risk of death.

Nutritional management of a patient with obesity and pulmonary embolism: a case report

Background

The aim of this case report is to discuss the issue of nutritional therapy in patients taking warfarin. Patients are often prescribed vitamin K free diets without nutritional counseling, leading to possible health consequences.

Case presentation

A 52-year-old woman with obesity and hypertension was prescribed a low calorie diet by her family doctor in an effort to promote weight loss. After a pulmonary embolism, she was placed on anticoagulant therapy and on hospital discharge she was prescribed a vitamin K free diet to avoid interactions. Given poor control of her anticoagulant therapy, she was referred to our Nutritional Unit outpatients’ service.

Conclusions

This case illustrates the importance of a thorough medical nutrition assessment in the management of patients with obesity and the need for a change in the dietary approach of nutritional therapy in the management of vitamin K anticoagulant therapy. In patients taking warfarin, evidence suggest that the aim of nutritional therapy should be to keep dietary intake of vitamin K constant.

Feasibility Study of a Mobile Health Intervention for Older Adults on Oral Anticoagulation Therapy

Background: Oral anticoagulation treatment (OAT) such as warfarin therapy is recommended for older adults with atrial fibrillation, heart failure, or who are at risk for venous thromboembolism. Despite its proven benefits, older adults report both dissatisfaction with OAT and reduced quality of life that can potentially lead to low adherence to OAT and decreased treatment efficacy. Objective: To test the feasibility of Mobile Applications for Seniors to enhance Safe anticoagulation therapy (MASS), a mobile-based health technology intervention designed to promote independence and self-care. Methods: This pilot study used a single-arm experimental pre–post design to test the feasibility of a 3-month intervention using MASS in 18 older adults (male: n = 14; White: n = 9; Hispanic: n = 7; Other: n = 2; M age = 67). MASS was available in English or Spanish. Participants completed surveys about their OAT knowledge, attitudes, quality of life with OAT, and adherence at baseline and at a 3-month follow-up. Satisfaction with the MASS intervention was also assessed at follow-up. Results: Anticoagulation knowledge significantly improved from baseline to follow-up (M_base = 12.5 ± 5.51, M_follow-up = 14.78 ± 3.93, p = .007). Other outcomes were not different, pre- and post-tests. Participants reported they were generally satisfied with MASS, its ease of use and its usefulness. Conclusion: The results showed use of MASS improved older adults’ knowledge of OAT. Using mHealth apps may enhance self-care among older adults with chronic conditions who are also taking oral anticoagulants.

Risk of recurrent venous thromboembolism after discontinuation of vitamin K antagonist treatment: a nested case-control study

Essentials Vitamin K antagonists (VKA) in venous thromboembolism (VTE) lower the risk of recurrences. 41 841 VKA-treated VTE patients had 1242 recurrent VTEs on therapy or early after cessation. An increased risk of recurrence was found in the first 120 days after VKA cessation. Patient education for the early detection of recurrent VTE after VKA cessation is recommended.

SUMMARY

Background The standard treatment for venous thromboembolism (VTE) and the prevention of recurrent VTE (rVTE) consists of anticoagulant therapy. The optimal duration of anticoagulation depends on the presence of risk factors for rVTE. Objectives To estimate the risk of rVTE in association with time since discontinuation of vitamin K antagonist (VKA) treatment. Methods From the UK Clinical Practice Research Datalink with linked information on hospitalization and cause of death, a cohort of patients with a first VTE receiving initial VKA treatment between 2001 and 2013 was formed. With a nested case-control approach, patients with incident rVTE (cases) were matched to patients with VTE but without rVTE (controls). Adjusted rate ratios (RRs) of rVTE associated with time since VKA discontinuation relative to current VKA use were estimated from conditional logistic regression. Results The VTE cohort comprised 41 841 patients with 1242 rVTEs and 6205 matched controls. The RR of rVTE was increased within 60 days following VKA discontinuation (RR 2.23, 95% confidence interval [CI] 1.71-2.91) and within 61-120 days following VKA discontinuation (RR 1.49, 95% CI 1.08-2.05) relative to current VKA use. The increased RR corresponded to excess incidence rates of 6.72 (95% CI 3.90-10.06) rVTE cases per 100 person-years within 60 days, and of 2.68 (95% CI 0.42-5.58) rVTE cases per 100 person-years within 61-120 days after VKA discontinuation. Conclusions VKA discontinuation results in a transient increased risk of rVTE, which peaks within 60 days and lasts for up to 120 days after VKA discontinuation. Specific patient education for increased vigilance for signs and symptoms of recurrences is recommended in this period.

Optional Vena Cava Filters: What, Why, and When

Optional vena cava filters can used to provide either short-term or permanent protection from pulmonary embolism. These devices have recently become available for clinical use in the United States. However, there remains a paucity of data about these devices and their outcomes. This article reviews current and future devices, the rationale behind non-permanent caval filtration, and the generally accepted guidelines for their clinical application.

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.

Protein N-linked homocysteine is associated with recurrence of venous thromboembolism

BACKGROUND

Recently, protein N-linked homocysteine (Hcy) has been measured in healthy subjects and patients with marked hyperhomocysteinemia. Since elevated total Hcy (tHcy) levels are associated with increased risk of venous thromboembolism (VTE), we aimed to investigate protein N-linked Hcy levels in patients with VTE.

METHODS

We studied 200 consecutive patients with VTE (89 men, 111 women, aged from 17 to 83 years), including 57 subjects with a subsequent episode of VTE (recurrent VTE) during 24 months of follow-up. Protein N-linked Hcy was assayed using high-performance liquid chromatography with an on-column derivatization with o-phthaldialdehyde and fluorescence detection.

RESULTS

The median protein N-linked Hcy was 1.404 μM (interquartile range [IQR] 0.859-2.066), while the median tHcy (IQR) was 9.1 μM (6.8-11.2). In the whole group protein N-linked Hcy correlated only with C-reactive protein (CRP; r = 0.44, p < 0.0001). In patients with recurrent VTE protein N-linked Hcy correlated with C-reactive protein (r = 0.43, p < 0.0001), tHcy (r = 0.42, p = 0.001) and age (r = 0.32, p = 0.014), but not with thrombophilia, unprovoked VTE or the current anticoagulation. Hyperhomocysteinemia, defined as tHcy ≥ 15 μM (n = 14.7%), was not associated with higher protein N-linked Hcy. Patients with recurrent VTE had higher levels of protein N-linked Hcy compared to those who experienced a single episode of VTE (1.553 μM, 1.157-2.445 vs. 1.27 μM, 0.826-1.884; p = 0.002). Multiple regression adjusted for potential confounders showed that the only independent predictor of protein N-linked Hcy in the upper quartile was CRP > 3mg/L (odds ratio 3.04, 95% confidence interval 2.12-4.36, p < 0.0001).

CONCLUSION

Elevated protein N-linked Hcy concentrations, indicating enhanced protein homocysteinylation in vivo, characterize patients with recurrent VTE and this phenomenon is associated with enhanced inflammatory state.

Perioperative management of bariatric surgery patients

PURPOSE

The perioperative management of bariatric surgery patients is described.

SUMMARY

Obesity and anatomical changes create unique challenges for clinicians when caring for bariatric surgery patients. Common bariatric surgery procedures performed include Roux-en-Y gastric bypass, sleeve gastrectomy, and adjustable gastric banding. Pain management in the acute postoperative period depends on careful dosing of opioid agents and the use of adjunctive agents. Prevention and management of infectious complications include appropriate surgical prophylaxis, monitoring and rapid treatment of suspected intra-abdominal infections, and detection and treatment of Helicobacter pylori infection. Venous thromboembolism (VTE) prophylaxis and treatment are complicated by obesity, and the use of pharmacologic agents must be balanced with bleeding risk. Bleeding is a serious complication that should be closely monitored in the immediate postoperative period. Blood products remain first-line therapy for the treatment of bleeding in this population. Acute differences in drug absorption as well as emerging hormonal changes necessitate the immediate postoperative adjustment of chronic medications to ensure both safety and efficacy. Pharmacists are valuable members of interprofessional teams for bariatric surgery patients because they provide expertise on the availability of dosage forms and dosage modification to ensure that patient pharmacotherapy is not interrupted; assist in the management of hypertension, diabetes, and psychotropic medications; and ensure appropriate antimicrobial prophylaxis and VTE prophylaxis and treatment dosages.

CONCLUSION

The management of patients in the perioperative period of bariatric surgery requires appropriate selection and dosing of medications for pain management and treatment of infectious complications, VTE, bleeding, and other chronic diseases.

Effect of CYP2C9 and VKORC1 genetic variations on warfarin dose requirements in Indian patients

BACKGROUND

Warfarin, an oral anticoagulant is used in patients who are at increased risk of developing blood clots. The management of warfarin therapy is challenging because it shows large inter and intra individual variability in patient response due to factors like age, gender, diet, concurrent drug interactions and variations in CYP2C9 and VKORC1 genes. Studies implicate that polymorphisms in VKORC1 and CYP2C9 genes are associated with reduced doses of warfarin. The aim of our current study was to characterize the effects of VKORC1 and CYP2C9 gene variations that contribute to variability in warfarin dosing in Indian patients.

METHODS

Genomic DNA was extracted from 103 patients undergoing warfarin therapy. Their mean daily warfarin dose, INR and demographics were recorded and genotyping of VKORC1 and CYP2C9 gene was performed by PCR-RFLP method.

RESULTS

Individuals with wild type genotypes required highest mean warfarin dosage of 4.72 mg/day while VKORC1 variants required 3.6 mg/day to maintain their therapeutic INR. CYP2C9*2 genotype was not found to affect the warfarin maintenance dosages. The odds ratio for developing supra therapeutic INR in patients carrying VKORC1 variant allele when compared to wild types was 13.96 (95% CI; 4.85 - 44.65. Other factors affecting warfarin dosages were age and weight.

CONCLUSION

Inclusion of pharmacogenetic data along with clinical parameters would help better predict warfarin doses in Indian patients.

Attitudes and preferences on the use of mobile health technology and health games for self-management: interviews with older adults on anticoagulation therapy

Background

Older adults are at substantial risk for cardiovascular disorders that may require anticoagulation therapy. Those on warfarin therapy report dissatisfaction and reduced quality of life (QOL) resulting from the treatment. Advances in the area of mobile health (mHealth) technology have resulted in the design and development of new patient-centric models for the provision of personalized health care services to improve care delivery. However, there is a paucity of research examining the effectiveness of mHealth tools on knowledge, attitudes, and patient satisfaction with treatment, as well as self-management, adherence to therapy, and QOL in older adults with chronic illness conditions requiring long-term warfarin therapy.

Objective

The objective of the study was to explore the attitudes and preferences of older adults on warfarin therapy regarding the use of mHealth technology and health games to gain skills for self-management.

Methods

We conducted group and individual interviews with patients (60 years or older) on warfarin therapy at two anticoagulation clinics affiliated with an academic medical center. We held 4 group and 2 individual interviews, resulting in 11 patient participants and 2 family caregiver participants. We used structured questions on three topic areas including medication self-management strategies, mHealth technology use, and health games for exercise. We demonstrated some commercial health apps related to medication management, vitamin K content of food, and a videogame for balance exercise. Discussions were audiotaped and transcribed verbatim. Common themes were drawn using content analysis.

Results

The participants reported awareness of the importance of staying on schedule with warfarin therapy. They also acknowledged that negative experiences of friends or family members who were taking warfarin influenced their desire to keep on schedule with warfarin therapy. In addition, the participants expressed that the use of mHealth technology may be helpful for medication management. They also expressed the need for family support in the use of health technology devices. Moreover, the participants discussed concerns and challenges to use health technology and health games, and provided suggestions on ways to make mHealth technology and health games elder-friendly.

Conclusions

These findings indicate that our older adults on warfarin therapy are interested in mHealth technology specific to warfarin medication management and health games. Further research needs to be done to validate these findings. Elder-friendly designs, technology support, and physical safety using mHealth technology may be useful in this population. These findings can be used to inform a larger study to design and test an elder-centered mHealth technology in this target population.

Management of acute stroke in patients taking novel oral anticoagulants

Each year, 1·0–2·0% of individuals with atrial fibrillation and 0·1–0·2% of those with venous thromboembolism who are receiving one of the novel oral anticoagulants (dabigatran, rivaroxaban, or apixaban) can be expected to experience an acute ischemic stroke. Additionally, 0·2–0·5% of individuals with atrial fibrillation who are receiving one of the novel oral anticoagulants can be expected to experience an intracranial hemorrhage. This opinion piece addresses the current literature and offers practical approaches to the management of patients receiving novel oral anticoagulants who present with an ischemic or hemorrhagic stroke. Specifically, we discuss the role of thrombolysis in anticoagulated patients with acute ischemic stroke and factors to consider concerning restarting anticoagulation after acute ischemic and hemorrhagic stroke.

Venous thromboembolism and postoperative management of anticoagulation

Deep venous thrombosis and pulmonary embolism are common after fragility fracture surgery, although the incidence is decreasing over time. Prophylaxis is important, because it is effective; additionally, the consequences are significant. Several medications are available for prophylaxis, and the choice of agent should be determined based on patient and surgery characteristics, and balancing of venous thromboembolism (VTE) and bleeding risk. A comprehensive approach to VTE prophylaxis includes consideration of a pharmacologic agent and nonpharmacologic management.

Incidence and predictors of venous thromboembolism recurrence after a first isolated distal deep vein thrombosis

BACKGROUND

Isolated distal deep vein thrombosis (iDDVT) (i.e. without proximal DVT or pulmonary embolism) represents half of all cases of lower limb DVT. Its clinical significance and management are controversial. Data on long-term follow-up are scarce, especially concerning risk and predictors of venous thromboembolism (VTE) recurrence.

METHODS

Using data from the OPTIMEV (OPTimisation de l'Interrogatoire dans l'évaluation du risque throMbo-Embolique Veineux) study, a prospective, observational, multicenter study, we compared, 3 years after an index VTE event and after discontinuation of anticoagulants, (i) the incidence and type of recurrence in patients without cancer with a first iDDVT vs. a first isolated proximal DVT (iPDVT) and (ii) predictors of recurrence after iDDVT.

RESULTS

Compared with patients with iPDVT (n = 259), patients with an iDDVT (n = 490) had a lower annualized incidence of overall VTE recurrence (5.2% [95% confidence interval 3.6-7.6] vs. 2.7% [1.9-3.8], respectively; P = 0.02) but a similar incidence of pulmonary embolism recurrence (1.0% [0.5-2.3] vs. 0.9% [0.5-1.6], respectively; P = 0.83). An age of > 50 years, unprovoked character of index iDDVT, and involvement of more than one vein in one or both legs each independently tripled the risk of recurrence, with the latter then being ≥ 3% per patient-year. Neither muscular vein nor deep-calf vein location of iDDVT nor clot diameter with compression influenced the risk of recurrence.

CONCLUSIONS

After stopping anticoagulants, patients with iDDVT have a significantly lower risk of overall VTE recurrence than did patients with iPDVT but a similar risk of serious recurrent VTE. Age > 50 years, unprovoked iDDVT, and number of thrombosed veins (more than one) influenced the risk of recurrence and may help to define patients at significant risk of recurrence.

Management of thrombotic complications in acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) is the most common type of cancer diagnosed in children, and has been reported as the most common malignancy associated with thromboembolism in the pediatric age group. Treatment with Escherichia coli asparaginase, concomitant steroids, presence of central venous lines, and thrombophilic abnormalities are established risk factors for thromboembolism. The incidence varies with age, co-morbidities and chemotherapy regimens but the risk is highest during the induction and intensification phases. Treatment is necessary in majority of children to prevent serious sequelae. Mortality from thromboembolic events in any location is 2 to 4 % and the risk of recurrence is 7 to 10 %, further enhanced in the setting of malignancy. Randomized trials of venous thromboembolism (VTE) management in pediatric patients with ALL are lacking due to the low overall incidence, resulting in considerable variation in practice. The objective of this article is to review current knowledge on the treatment and prevention of thrombosis associated with pediatric ALL.

Shear wave induced resonance elastography of venous thrombi: a proof-of-concept

Shear wave induced resonance elastography (SWIRE) is proposed for deep venous thrombosis (DVT) elasticity assessment. This new imaging technique takes advantage of properly polarized shear waves to induce resonance of a confined mechanical heterogeneity. Realistic phantoms (n = 9) of DVT total and partial clot occlusions with elasticities from 406 to 3561 Pa were built for in vitro experiments. An ex vivo study was also performed to evaluate the elasticity of two fresh porcine venous thrombi in a pig model. Transient shear waves at 45-205 Hz were generated by the vibration of a rigid plate (plane wavefront) or by a needle to simulate a radiation pressure on a line segment (cylindrical wavefront). Induced propagation of shear waves was imaged with an ultrafast ultrasound scanner and a finite element method was developed to simulate tested experimental conditions. An inverse problem was then formulated considering the first resonance frequency of the DVT inclusion. Elasticity agreements between SWIRE and a reference spectroscopy instrument (RheoSpectris) were found in vitro for total clots either in plane (r(2) = 0.989) or cylindrical (r(2) = 0.986) wavefront configurations. For total and partial clots, elasticity estimation errors were 9.0 ±4.6% and 9.3 ±11.3%, respectively. Ex vivo, the blood clot elasticity was 498 ±58 Pa within the inferior vena cava and 436 ±45 Pa in the right common iliac vein (p = 0.22). To conclude, the SWIRE technique seems feasible to quantitatively assess blood clot elasticity in the context of DVT ultrasound imaging.

Comparison of percutaneous ultrasound-accelerated thrombolysis versus catheter-directed thrombolysis in patients with acute massive pulmonary embolism

Acute massive pulmonary embolism (PE) is a life-threatening condition that requires prompt and aggressive interventions, including anticoagulation, catheter-directed thrombolysis (CDT), mechanical thrombectomy, or surgical thromboembolectomy. The aim of this study was to evaluate the treatment outcome in patients with massive PE who were treated with either ultrasound-accelerated thrombolysis using the EkoSonic Endovascular System (EKOS) or CDT intervention. During a recent 10-year period, the clinical records of all patients with massive PE undergoing catheter-directed interventions were evaluated. Patients were divided into two treatment groups: EKOS versus CDT interventions. Comparisons were made with regard to the treatment outcome between the two groups. Twenty-five patients underwent 33 catheter-directed interventions for massive PE during the study period. Among them, EKOS or CDT was performed in 15 (45%) and 18 (55%) procedures, respectively. In the EKOS group, complete thrombus removal was achieved in 100% cases. In the CDT cohort, complete or partial thrombus removal was accomplished in 7 (50%) and 2 (14%) cases, respectively. Comparing treatment success based on thrombus removal, EKOS treatment resulted in an improved treatment outcome compared with the CDT group (p < .02). The mean time of thrombolysis in EKOS and CDT group was 17.4 +/- 5.23 and 25.3 +/- 7.35 hours, respectively (p = .03). The mortality rate in the EKOS and CDT group was 9.1% and 14.2%, respectively (not significant). Treatment-related hemorrhagic complication rates in the EKOS and CDT group were 0% and 21.4%, respectively (p = .02). A significant reduction in Miller scores was noted in both groups following catheter-based interventions. No significant difference in relative Miller score improvement was observed between groups. Ultrasound-accelerated thrombolysis using the EkoSonic system is an effective treatment modality in patients with acute massive PE. When compared with CDT, this treatment modality provides similar treatment efficacy with reduced thrombolytic infusion time and treatment-related complications.

Antiphospholipid syndrome

The antiphospholipid syndrome (APS) is an autoimmune systemic disease that is diagnosed when there is vascular thrombosis and/or pregnancy morbidity occurring with persistently positive antiphospholipid antibodies (aPL) (lupus anticoagulant test, anticardiolipin antibodies, and/or anti-beta(2)-glycoprotein I antibodies). Although International APS Classification Criteria have been formulated to provide a uniform approach to APS research, aPL may cause a spectrum of clinical manifestations, some of which are not included in these criteria. The main aPL-related cardiac manifestations include valve abnormalities (vegetations and/or thickening), myocardial infarction (MI), intracardiac thrombi, and myocardial microthrombosis. In this article, we will review the definition, etiopathogenesis, clinical manifestations, diagnosis, and treatment of aPL-related clinical events with emphasis on cardiac manifestations.

High rate of unprovoked recurrent venous thrombosis is associated with high thrombin-generating potential in a prospective cohort study

OBJECTIVE

To determine the predictive value of measurement of parameters of thrombin generation for unprovoked recurrent venous thrombosis.

METHODS

Measurements were made of thrombin generation in a prospective cohort study of 188 patients with a first episode of venous thrombosis that was unprovoked, or provoked by a non-surgical trigger.

RESULTS

The endogenous thrombin potential (ETP) was the only parameter associated with unprovoked recurrent thrombosis in a multivariate model [hazard ratio (HR) 1.3 per 100 nmol L min(-1) increase, 95% confidence interval (CI) 1.0-1.6]. Patients with a high ETP had a significantly higher rate of unprovoked recurrence than those with a low ETP (HR 2.9, 95% CI 1.3-6.6, cumulative recurrence at 4 years 27% vs. 11%). Patients with an unprovoked first event had a significantly higher rate of unprovoked recurrence than those with a provoking factor (HR 2.7, 95% CI 1.2-6.1), and in these patients there was a significantly higher rate of unprovoked recurrence in association with a high ETP (HR 4.0, 95% CI 1.3-11.8). After adjustment for D-dimer, thrombophilia, sex, and whether or not the first event was unprovoked, a high ETP remained a significant predictor of recurrence (HR 2.6, 95% CI 1.2-6.0).

CONCLUSIONS

This study demonstrates a high rate of unprovoked recurrent venous thrombosis in patients presenting with a first episode of venous thrombosis and a high ETP.

The utility of thrombophilia testing in pregnant women with thrombosis: fact or fiction?

Women who either present with an episode of acute venous thrombosis in pregnancy or who have a history of venous thrombosis who present for prenatal care often undergo testing for inherited thrombophilia. The rationale for screening may include questions about whether screening for inherited thrombophilias can help to alter anticoagulation plans in a pregnancy complicated by venous thrombosis, whether patients with a history of venous thrombosis who present for care in a subsequent pregnancy require anticoagulation and at what intensity, whether knowledge of thrombophilia changes the duration and intensity of anticoagulation outside pregnancy, and whether screening of family members is warranted. Data regarding these issues are reviewed, controversies surrounding thrombophilia testing in this setting are discussed, and clinical recommendations are made.

Body mass index and mortality in patients with acute venous thromboembolism: findings from the RIETE registry

BACKGROUND

There is little information on the influence of body mass index (BMI) on mortality in patients with acute venous thromboembolism (VTE).

PATIENTS AND METHODS

RIETE is an ongoing registry of consecutive patients with symptomatic, objectively confirmed, acute VTE. We examined the association between BMI and mortality during the first 3 months of therapy.

RESULTS

Of the 10 114 patients enrolled as of March 2007: 153 (1.5%) were underweight (BMI < 18.5); 2882 (28%) had a normal weight (BMI 18.5-24.9); 4327 (43%) were overweight (BMI 25.0-30); and 2752 (27%) were obese (BMI > 30). The overweight and obese patients were significantly older, and were less likely to have had cancer, recent immobility or renal insufficiency. After 3 months of therapy their death rates were 28%, 12%, 6.2% and 4.2%, respectively. In multivariate analysis, the relative risks for death after adjusting for confounding variables including age, cancer, renal insufficiency or idiopathic VTE were: 2.1 (95% CI, 1.5-2.7); 1.0 (reference); 0.6 (95% CI, 0.5-0.7); and 0.5 (95% CI, 0.4-0.6), respectively. The rates of fatal pulmonary embolism (2.0%, 2.1%, 1.2% and 0.8%, respectively) also decreased with BMI. There were no differences in the rate of fatal bleeding, but patients who were underweight had an increased incidence of major bleeding complications (7.2% vs. 2.7%; odds ratio, 2.7; 95% CI, 1.4-5.1).

CONCLUSIONS

Obese patients with acute VTE have less than half the mortality rate when compared with normal BMI patients. This reduction in mortality rates was consistent among all subgroups and persisted after multivariate adjustment.

FV Leiden mutation and risk of recurrent venous thromboembolism in Serbian population

The absolute rate of recurrence of venous thromboembolism (VTE) is approximately 5% per year. There is a lower rate of recurrence in provoked VTE, and higher in idiopathic one. So far, there is no consensus whether hereditary thrombophilia should be considered as a persistent risk factor, and whether it requires long-term anticoagulant therapy. The aim of our study was to estimate the risk of recurrent VTE in patients carrying FV Leiden mutation in Serbian population. In retrospective study (1994-2006), we have evaluated the risk of recurrent VTE in 56 patients who are carriers of FV Leiden mutation, in comparison to group consisting of 56 patients non-carriers of FV Leiden mutation. Patients with FII G20210A and MTHFR C677T mutations, antiphospholipid antibodies, antithrombin III, protein C or protein S deficiency, malignancies and diabetes were excluded from the study. Recurrent VTE occurred in 44.6% of the patients, carriers of the FV Leiden mutations, vs. 26.7% in non-carriers group (P<0.05). The incidence rate was 3.7 and 2.2% per year, respectively. The estimated relative risk of recurrence for FV Leiden carriers was 1.67 (95% CI 0.99-2.81, P=0.049). The 60% of patients with mutation and only 13% without mutation develop rethrombosis during first year after discontinuance of therapy (P<0.01). In our study patients with symptomatic VTE who are carriers of the FV Leiden gene mutations have a higher risk of recurrent VTE than non-carriers. Our data suggest the importance of the FV Leiden mutation detection and the estimation of the clinical condition for successful secondary prophylaxis of VTE.

The impact of venous thromboembolism on risk of death or hemorrhage in older cancer patients

BACKGROUND

Among older cancer patients, there is uncertainty about the degree to which venous thromboembolism (VTE) and its treatment increase the risk of death or major hemorrhage.

OBJECTIVE

To determine the prevalence of VTE in a cohort of older cancer patients, as well as the degree to which VTE increased the risk of death or major hemorrhage.

METHODS

We conducted a retrospective cohort study of linked Surveillance, Epidemiology, and End Results cancer registry and Medicare administrative claims data. Patients with any of ten invasive cancers diagnosed during 1995 through 1999 were included; the independent variable was VTE diagnosed concomitantly with cancer diagnosis. Outcomes included major hemorrhage during the first year after cancer diagnosis and all-cause mortality;

RESULTS

Overall, about 1% of patients who were diagnosed with cancer also had a VTE diagnosed concomitantly. After adjusting for sociodemographic factors and cancer stage and grade, concomitant VTE was associated with a relative increase in the risk of death for 8 of the 10 cancer types; the increase in risk tended to range 20-40% across most cancer types. Approximately 16.8% (95% confidence interval [CI] 14.9-18.8%) of patients with a concomitant VTE and 7.9% (95% CI 7.7-8.0%) of patients without a VTE experienced a major hemorrhage during the year after cancer diagnosis (P value <.001). The excess risk of hemorrhage associated with VTE varied substantially across cancer types, ranging from no significant excess (kidney and uterine cancer) to 11.5% (lymphoma).

CONCLUSION

Concomitant VTE is not only a marker and potential mediator of increased risk of death among older cancer patients, but patients with a VTE have a marked increased risk of major hemorrhage.