Antithrombotic therapy for venous thromboembolic disease

Once-daily Compared With Twice-daily Enoxaparin Maintenance Therapy Appears Safe and Efficacious in Pediatric Venous Thromboembolism

INTRODUCTION

Once-daily enoxaparin (ODE), considered standard of care for venous thromboembolism (VTE) treatment in adults, has been infrequently assessed in children. To contribute available data to a limited field, we reviewed our center's experience with ODE in treating pediatric VTE compared with twice-daily enoxaparin (TDE).

MATERIALS AND METHODS

A retrospective analysis of children and adolescents 18 years of age or below diagnosed with VTE and treated at our institution with ODE or TDE maintenance therapy between April 2015 and December 2020 was performed. Patient demographics, clinical and laboratory data pertaining to VTE diagnosis, and management were gathered from electronic medical records and compared between the 2 cohorts.

RESULTS

Seventy-one children met the eligibility criteria. All patients were initially treated with TDE for 2 weeks before transitioning to ODE maintenance therapy (n=39; 55%) or continuing with TDE dosing (n=32; 45%).Extremity VTE was more common in ODE ( P =0.051) versus pulmonary/intracardiac sites in TDE ( P =0.002) when compared with other sites. Median enoxaparin dosing was 1.5 and 1.1 mg/kg/dose in ODE and TDE cohorts, respectively. Bleeding episodes were rare without any difference between the cohorts. Two patients (6%) were lost to follow up in TDE cohort. All evaluable patients in both cohorts had either complete/partial response (ODE n=35 [90%]; TDE n=24 [75%] or stable thrombus ODE n=4 [10%]; TDE n=6 [19%]).

CONCLUSIONS

Our results indicate that ODE, used after the initial TDE treatment period, is as safe and efficacious as TDE maintenance for the treatment of pediatric VTE. The difference in VTE sites may have contributed to the equal efficacy of both the cohorts. Future prospective studies in pediatric VTE are needed to validate these results.

Safety and Efficacy of Rivaroxaban for Extended-Phase Anticoagulation of Patients with Unprovoked or Recurrent Venous Thromboembolism: Real-Life Data from the MAC Project

Venous thromboembolism (VTE) is a major cause of death in the world. After the acute-phase treatment, the optimal duration of anticoagulation is still debatable. The latest guidelines suggest maintaining long-term anticoagulation in patients with cancer-associated thrombosis (CAT) or with unprovoked VTE and a low bleeding risk. Methods: The MAC Project is an ongoing prospective-cohort, multi-center, observational study in Italy. The project aims to collect real-life clinical information in unselected patients given oral anticoagulants for VTE over a 5-year follow-up period. There were no exclusion criteria, except for life expectancy <6 months and refusal to sign the informed consent form or to attend the planned follow-up visit. All patients were followed-up prospectively with clinical controls scheduled at 3, 6, and 12 months after the index event, and then annually for up to 5 years. The primary efficacy and safety outcomes were symptomatic recurrent VTE and major bleeding. Results: We analyzed 450 consecutive patients treated with rivaroxaban and referred them to the MAC Project database for unprovoked or recurrent VTE. Of these, 267 (55%) were unprovoked VTE, and 377 (87%) were symptomatic. We followed up with the patients for a mean of 22 months (Q1 10.7; Q3 37.4 months). Recurrent VTE occurred in 12 patients on rivaroxaban treatment (IR 1.7 per 100 person-years). Males had more recurrence than women. During the follow-up period, we recorded 13 (2.9%) major bleeding, 12 (2.7%) clinically relevant non-major bleeding, 8 minor bleeding, and no fatal bleeding events. Overall, bleeding events occurred in 33 (7.3%) patients, most occurring within the first 2 years of treatment. In addition, we observed a statistically significant higher incidence of bleeding in patients with a baseline HAS-BLED score of 3 to 4 compared with those with a score of 0 to 2, with most events occurring during the first 3 months of treatment (RR 5.9). Discussion: Rivaroxaban appears to be safe and effective for the long-term treatment of patients with recurrent or unprovoked VTE. Our results match previously published data, and we are confident that the continuation of the follow-up for up to 5 years will confirm these outcomes.

Secondary prevention of venous thromboembolism: Predictors and outcomes of guideline adherence in a long-term prospective cohort study

Background

Prevention of recurrent venous thromboembolism (VTE) is considered a main goal of VTE management. However, the extent to which physicians adhere to the recommendations from evidence-based guidelines is unknown.

Aim

From a large, prospective clinical cohort, we aimed to (1) quantify the adherence of treatment recommendations to evidence-based guidelines and establish its predictors, and (2) estimate its impact on clinical outcomes and costs in patients with VTE.

Methods

We included 6'243 consecutive patients with VTE treated at the university outpatient unit. Detailed clinical characteristics and treatment recommendations were recorded. Adherence of treatment recommendations to evidence-based guidelines at risk assessment was assessed in terms of duration of anticoagulant treatment. Data on death were obtained from the Swiss Central Compensation Office. Health care claims data recorded between 2014 and 2019 were retrieved from Helsana, one of the largest Swiss health insurance companies.

Results

The adherence to evidence-based guidelines was 36.1%. Among patients with non-adherence, overtreatment was present in 70.1%. Significant patient-related predictors of guideline adherence were (a) age above 50 years, (b) male sex, (c) pulmonary embolism, (d) unprovoked VTE, (e) multiple VTE, (f) laboratory tests not ordered, and (g) various cardiovascular comorbidities. Non-adherence was not significantly associated with mortality, hospitalization, admission to nursing home, and costs.

Conclusions

The adherence to evidence-based guidelines was low, and several unrelated predictors appeared. Although these results need to be confirmed in other settings, they highlight the need for implementation of evidence-based guidelines in clinical practice.

Predicting the risk of recurrent venous thromboembolism: Impact and therapeutic consequences of inherited thrombophilia

BACKGROUND

Over the past decades, thrombophilia testing in patients with venous thrombo-embolism has increased tremendously. However, the role of inherited thrombophilie in prediction the risk of recurrence remains controversial. Consequently, it is still unclear whether thrombophilia testing influences decisions regarding duration of anticoagulation in clinical practices. The aim of this study was to evaluate the impact if inherited thrombophilia on venous thrombosis treatment decisions and on predicting the risk of recurrence.

METHODS

A retrospective longitudinal study (January 2011-Decembre 2016) including 131 patients with confirmed venous thrombo-embolism referred to the hematology laboratory from the internal medicine department for inherited thrombophilia screening was carried out.

RESULTS

The mean age patients was 39.4 years and the sex ratio (M/F) was 0.61. Inherited thrombophilia was confirmed in 27.5% of patients. A long term anticoagulation was decided in 46.9% of patients with thrombophilia. There was no significant difference in the duration of anticoagulation between patients with or without thrombophilia. Thrombosis recurrence was recorded in 16 (17%) patients. The 24 years cumulative incidence of recurrence was 19% in patients with thrombophilia and 17% in those without (plog Rank= 0.6). Inherited thrombophilia was not associated with increased risk of recurrence after treatment withdrawal (Hazard ratio=1.31 IC (0.47-3.63); P=0.6).

CONCLUSION

In clinical practice, inherited thrombophilia did not influence anticoagulation duration and was not associated with a higher venous thrombosis risk of recurrence. It seems to be less relevant for decision making than presumed.

Risk Factors of Unfavorable Outcomes, Major Bleeding, and All-Cause Mortality in Patients with Venous Thromboembolism

Purpose

This study aimed to analyze the clinical outcomes of venous thromboembolism (VTE) patients and identify the risk factors for VTE-related unfavorable outcomes, major bleeding, and 30-day all-cause mortality.

Materials and Methods

From January 2016 to December 2020, 198 patients with confirmed VTE were enrolled. Potential risk factors for unfavorable outcomes, major bleeding, and all-cause mortality were analyzed.

Results

VTE-related unfavorable outcomes developed in 13.1%, while 30-day all-cause mortality was 8.6%. In the multivariate analysis, a pulse ≥110/min and respiratory rate ≥30/min were statistically significant predictors for VTE-related unfavorable outcomes. Diabetes was a significant risk factor for major bleeding. In addition, a history of malignancy, no anticoagulation treatment, and need for mechanical ventilation were significant predictors of all-cause mortality.

Conclusion

VTE-related mortality and morbidity rates remained high. In cases of tachycardia and tachypnea, early aggressive treatment is needed to prevent unfavorable outcomes. Patients with risk factors should be closely monitored.

Validation of the IMPEDE VTE score for prediction of venous thromboembolism in multiple myeloma: a retrospective cohort study

The IMPEDE VTE score has recently emerged as a novel risk prediction tool for venous thromboembolism (VTE) in multiple myeloma (MM). We retrospectively reviewed 839 patients with newly diagnosed MM between 2010 and 2015 at Cleveland Clinic and included 575 patients in final analysis to validate this score. The c-statistic of the IMPEDE VTE score to predict VTE within 6 months of treatment start was 0·68 (95% CI: 0·61-0·75). The 6-month cumulative incidence of VTE was 5·0% (95% CI: 2·1-7·9) in the low risk group, compared to 12·6% (95% CI: 8·9-16·4%) and 24·1% (95% CI: 12·2-36·1) in the intermediate and high risk groups (P < 0·001 for both). In addition, a higher proportion of patients in the VTE cohort had ECOG performance status of ≥2 as compared to the no VTE cohort (33% vs. 16%, P = 0·001). Other MM characteristics such as stage, immunoglobulin subtype, and cytogenetics were not predictors of VTE. In summary, we have validated the IMPEDE VTE score in our patient cohort and our findings suggest that it can be utilized as a VTE risk stratification tool in prospective studies looking into investigating VTE prophylaxis strategies in MM patients.

Unfractionated heparin dosing in obese patients

Background The effect of obesity on the pharmacokinetics and pharmacodynamics of unfractionated heparin is not clearly understood, therefore to reduce the risk of bleeding, maximal dose (capped) nomograms are often used. This can lead to inadequate anticoagulation and increased mortality and morbidity. In Queensland, Australia, statewide nomograms recommend total-body-weight-based dosing, with capped initial bolus and maintenance doses. Objective To determine if current practices for unfractionated heparin dosing leads to inadequate anticoagulation in obese patients. Setting Princess Alexandra Hospital, Queensland, Australia. Method A retrospective audit of unfractionated heparin dosing in 200 patients divided into cohorts of; < 100 kg (defined as non-obese), 100-124.9 kg, 125-150 kg and > 150 kg, Main outcomes measured Mean maintenance doses in U/h and U/kg/h required to achieve two consecutive therapeutic activated partial thromboplastin times' and the corresponding time to achieve this endpoint. Results The mean ± standard deviation maintenance doses required to achieve two consecutive therapeutic activated partial thromboplastin times' in U/h were 1229 ± 316, 1673 ± 523, 2031 ± 596 and 2146 ± 846, and in U/kg/h were 16 ± 4.1, 15.1 ± 4.8, 14.9 ± 4.2 and 11.6 ± 4.2 for the weight cohorts respectively. The median time (inter-quartile range) to therapeutic activated partial thromboplastin times' for obese patients was 39 (21.5-56) h. Conclusions Our results suggest inadequate dosing in obese patients. We recommend the use of larger absolute doses (U/h) of nfractionated heparin but reduced uncapped total body weight-based doses-(U/kg/h) as patient weight increases.

Effectiveness of Inferior Vena Cava Filters in Patients With Stable and Unstable Pulmonary Embolism and Trends in Their Use

BACKGROUND

Trends in the use of inferior vena cava (IVC) filters in patients with pulmonary embolism (PE) who are stratified according to whether they are stable or unstable (in shock or ventilator dependent) may show where improvements of management could be made according to the best evidence that we now have.

METHODS

This was a retrospective cohort study based on administrative data, 1999-2014, from the National (Nationwide) Inpatient Sample.

RESULTS

In-hospital all-cause mortality in unstable patients who received an IVC filter was lower in each year of investigation and in all age groups. Mortality from 1999 to 2014 was 10,140 of 35,230 (28.8%) with an IVC filter compared with 54,018 of 116,642 (46.3%) without a filter (P <0.0001). In stable patients from 1999 to 2014, mortality with an IVC filter was 31,909 of 546,858 (5.8%) with an IVC filter compared with 220,443 of 3,367,783 (6.5%) without a filter (P <0.0001). In patients ages > 80 years, mortality in stable patients with an IVC filter was 7,438 of 114,457 (6.5%) with an IVC filter compared with 64,113 of 567,348 (11.3%) without an IVC filter (P <0.0001). The number of stable patients who received an IVC filter decreased from 2010 to 2014, but even in those years the largest number of IVC filters was inserted in stable patients, 194,502 of 212,611 (91.5%).

CONCLUSIONS

Mortality is markedly reduced in unstable patients who receive an IVC filter. Despite this, the proportion of unstable patients who receive an IVC filter is decreasing. The largest number of IVC filters continues to be inserted in stable patients, although there is no evidence of a clinically meaningful reduced mortality with IVC filters in stable patients unless age >80 years.

Deep vein thrombosis cured by homeopathy: A case report

Venous thrombosis (VT) of deep vein is a life-threatening condition which may lead to sudden death as an immediate complication due to formation of thrombo-embolism. VT is associated with various risk factors such as prolonged immobilization, inflammation, and/or coagulation disorders including muscular or venous injury. Deep venous thrombosis (DVT) frequently occurs in the lower limb. Successful treatment of DVT exclusively with homeopathic remedies has rarely been recorded in peer-reviewed journals. The present case report intends to record yet another case of DVT in an old patient totally cured exclusively by the non-invasive method of treatment with micro doses of potentized homeopathic drugs selected on the basis of the totality of symptoms and individualization of the case. Since this report is based on a single case of recovery, results of more such cases are warranted to strengthen the outcome of the present study.

Digital Ischemia Following Brachial Artery Cannulation in a Polytrauma Patient: A Case-Based Discussion of Etiopathogenesis and Management

Iatrogenic digital ischemia following inadvertent intra-arterial injections is well documented. Most of the culprit drugs are used for sedation or in general anesthesia. Proper understanding of the causative factors and pathophysiology is of utmost importance for adequate treatment. There have been conflicting evidences in the numerous studies and theories proposed regarding pathophysiology. We scoped the available literature to find out the cause of digital ischemia in one of the patients presented to us but could not find a convincing answer. Due to incomplete understanding of the pathophysiology, there is no specific treatment protocol. Most important is vigilance regarding risk factors, knowledge of typical medications, immediate recognition of the situation, assessment of the disease progression, anticoagulation, symptomatic treatment, and specific therapy (which varies from case to case) are mainstay of treatment. Further research is warranted to understand the etiopathogenesis so that proper treatment protocol could be established.

Bemiparin as a long-term treatment for venous thrombosis in cancer patients: the ELEBAMA study

INTRODUCTION

Low-molecular-weight heparin (LMWH) is the standard treatment for cancer-associated venous thromboembolism (VTE). There have been no specific studies evaluating bemiparin for VTE in people with cancer. The aim of this study is to evaluate the effects of bemiparin for long-term treatment of VTE in routine clinical practice.

METHODS/PATIENTS

Prospective observational study. Consecutive patients with active cancer and VTE, under treatment with bemiparin for at least 6 months, were recruited.

RESULTS

We included 89 patients. The 6- and 9-month cumulative VTE recurrence rates were 2.4% and 5.9%, respectively. The 6-month cumulative rate of major bleeding was 1.3%, and of clinically relevant non-major bleeding, 8%.

CONCLUSIONS

The incidence of events in this study is lower than that reported in randomized trials. Bemiparin is effective and safe for the long-term treatment of cancer-associated VTE in routine clinical practice.

Retrieval of Inferior Vena Cava Filters Temporarily Placed in a Suprarenal Position: A Review of 13 Patients

Purpose:

To evaluate the safety and efficacy of retrieval of inferior vena cava filters (IVCF) temporarily placed in a suprarenal position.

Methods:

Retrieval of IVCF placed in a suprarenal position was performed in 13 patients (5 men and 8 women; mean age: 45.1 ± 13.8 years) between July 2006 and May 2018 using either a loop snare technique or endobronchial forceps. Electronic medical records were reviewed for patient demographics and procedural information.

Results:

Inferior vena cava filters retrieved included Option Elite (n = 9, 69%) and Günther Tulip (n = 4, 31%). Caval thrombosis was not detected in any patients on pre- or postretrieval cavogram. Eleven suprarenal IVCF (84%) were retrieved during the first retrieval attempt after a median indwelling time of 1.8 months (range, 0.03-12.10 months). Retrieval was initially unsuccessful in 2 (16%) patients with Option Elite filters, but both were successfully removed on second attempt using endobronchial forceps. Thirteen suprarenal IVCF (100%) were ultimately retrieved.

Conclusion:

Endovascular retrieval of IVCF temporarily placed in a suprarenal position is safe and efficacious.

Risk of recurrent venous thromboembolism according to baseline risk factor profiles

The optimal duration of anticoagulation for venous thromboembolism (VTE) is uncertain. In this prespecified analysis, we used data from 2 randomized trials, which compared once-daily rivaroxaban (20 mg or 10 mg) with aspirin (100 mg) or placebo for extended VTE treatment to estimate the risk of recurrence according to baseline risk factor profiles. Index VTE events were centrally classified as unprovoked, or provoked by major transient or persistent, or minor transient or persistent risk factors, and rates of recurrence at 1 year were calculated. A total of 2832 patients received rivaroxaban; 1131 received aspirin, and 590 received placebo. With unprovoked VTE, rates of recurrence in the 1173 patients given rivaroxaban, the 468 given aspirin, and the 243 given placebo were 2.0%, 5.9%, and 10.0%, respectively. There were no recurrences in patients with VTE provoked by major transient risk factors. With VTE provoked by minor persistent risk factors, recurrence rates in the 1184 patients given rivaroxaban, the 466 given aspirin, and the 248 given placebo were 2.4%, 4.5%, and 10.7%, respectively. For patients with minor transient risk factors, recurrence rates were 0.4% in the 268 patients given rivaroxaban, 4.2% in the 121 given aspirin, and 7.1% in the 56 given placebo. Recurrence rates in patients with VTE provoked by minor persistent or minor transient risk factors were not significantly lower than that with unprovoked VTE (hazard ratio [HR], 0.81; 95% confidence interval [CI], 0.56-1.16; and HR, 0.68; 95% CI, 0.32-1.30, respectively). Therefore, such patients may also benefit from extended anticoagulation therapy.

Systematic Review of Real-World Studies Evaluating Characteristics Associated With or Programs Designed to Facilitate Outpatient Management of Deep Vein Thrombosis

Select patients with acute deep vein thrombosis (DVT) can be managed as outpatients. We sought to conduct a systematic review of real-world studies describing either (1) the clinical characteristics associated with outpatient DVT treatment in all-comers or (2) emergency department (ED) programs designed to facilitate outpatient DVT treatment. MEDLINE and SCOPUS were searched (January 1, 2012, to May 1, 2018) to identify citations meeting the aforementioned criteria. Twenty-one real-world studies were included. The proportion of all-comer patients with DVT managed as outpatients was ≤50% in 11 of 15 studies. With the exception of younger age, no characteristics were consistently associated with outpatient treatment across the 13 studies reporting these characteristics. We identified 8 studies describing ED programs aimed at facilitating DVT outpatient treatment, all of which provided education and included measures to encourage early outpatient follow-up after ED discharge. In conclusion, the proportion of patients with DVT managed as outpatients across real-world studies was low. Several ED programs aimed at facilitating this treatment have been described. It is possible that programs similar to these will increase the proportion of patients with DVT that can be safely managed as outpatients.

Inferior Vena Cava Filters and Prevention of Recurrent Pulmonary Embolism

Although inferior vena cava (IVC) filters have a clear role in preventing recurrent pulmonary embolism (PE) in patients with venous thromboembolism who cannot be anticoagulated, the role of filters in patients who are candidates for anticoagulation is controversial. With limited and conflicting data, practitioners often have to make an educated patient-specific decision when encountering this scenario. This article reviews the available data on the efficacy and risks associated with adjunctive IVC filter use to prevent recurrent PE.

Calibration of interface properties and application to a finite element model for predicting vena cava filter-induced vein wall failure

We present a computational framework that integrates experimental techniques and finite element modeling to calibrate material fracture parameters of the vena cava and the interaction properties between a retrievable filter (Günther Tulip) and the vena cava wall. The fitted parameters were then used to analyze the interaction of the inferior vena cava filter with the vena cava during the deployment process. An idealized cava finite element model was then developed including residual stresses and physiological pressure conditions. Filter deployment was simulated, and a comprehensive study of tissue-filter interaction was performed by cohesive surface modeling. Simulations predict that there are no fracture areas for either model, so we can conclude that there is no penetration of the anchor into the vena cava. This suggests there are other physiological situations, such as the Valsalva maneuver, which could produce this penetration observed on some patients.

Safety and Efficacy of Enoxaparin Treatment in Venous Thromboembolic Disease during Acute Leukemia

Background

Venous thromboembolism (VTE) is a quite common complication in acute leukemia, although its real incidence is unknown. The best treatment of this complication is still a matter of debate due to the very high risk of hemorrhage in this group of patients.

Patients and methods

From December 2000 to December 2002 four Caucasian patients with acute leukemia developed VTE complications. The patients were three men and one woman, mean age 55.7 years (range, 27-77). Two patients with acute lymphoid leukemia (L1 and L2 according to the FAB classification) developed deep venous thrombosis during the administration of chemotherapy; one patient with acute myeloid leukemia (AML, M2 according to the FAB classification) had pulmonary thromboembolism at diagnosis, while another AML patient (M4 according to FAB) showed deep venous thrombosis as the first symptom of leukemia. The clinical diagnosis of symptomatic VTE was confirmed by objective imaging procedures including lower limb venous color Doppler imaging in all cases and a ventilation-perfusion lung scan in one case. All patients were treated with enoxaparin 100 IU/kg subcutaneously twice daily for one month, followed by 150 IU/kg once daily for at least five months. When the platelet count was below 20,000 × 109/L, the dose was reduced by 50%.

Results

During antithrombotic treatment neither VTE recurrences nor hemorrhagic complications or heparin-induced thrombocytopenia occurred. The platelet count at the beginning of enoxaparin treatment was very low (mean, 55,750 × 109/L; range, 12,000-121,000 × 109/L) and treatment did not affect platelet recovery.

Conclusions

Enoxaparin proved to be efficacious and safe in the management of deep venous thrombosis with or without pulmonary embolism in patients affected by acute leukemia. Enoxaparin cured acute venous thrombosis, prevented recurrences and did not cause any hemorrhagic complications despite prolonged severe thrombocytopenia.

Health Care Resource Utilization and Costs Among Newly Diagnosed and Oral Anticoagulant-Naive Nonvalvular Atrial Fibrillation Patients Treated with Dabigatran or Warfarin in the United States

BACKGROUND

Warfarin has a long history of use to reduce the risk of stroke in patients with atrial fibrillation (AF), but it requires frequent laboratory monitoring to maintain international normalized ratio levels in the therapeutic range. Dabigatran, a novel oral anticoagulant (OAC), has demonstrated efficacy in reducing the risk of stroke and systemic embolism and does not require laboratory monitoring.

OBJECTIVE

To compare health care resource utilization (HCRU) and costs of OAC-naive patients newly diagnosed with nonvalvular atrial fibrillation (NVAF), using dabigatran or warfarin.

METHODS

This retrospective observational study used data from medical and pharmacy claims extracted from the HealthCore Integrated Research Database representing commercial and Medicare Advantage members. Adults aged > 18 years with a medical diagnosis claim of NVAF were identified between October 1, 2010, and December 31, 2011. The date of first observed OAC prescription claim was the index date. Patients were followed for up to 12 months after the index date. Patients were assigned to the dabigatran or warfarin treatment groups based on their first OAC prescription fills. To reduce potential for selection bias, the cohorts were matched on baseline characteristics using propensity score matching. HCRU was measured and compared between groups on a per-patient-per-month (PPPM) basis for all-cause HCRU, as well as stroke, myocardial infarction, and bleed-specific HCRU. Pharmacy, medical, and total costs were also compared and adjusted to 2012 U.S. dollars. Generalized linear models were conducted to compare all-cause health care costs between cohorts.

RESULTS

After propensity score matching, 1,648 patients were included in the analysis (824 each in the dabigatran and warfarin treatment groups). In the post-index period, patients in the dabigatran group had significantly fewer all-cause PPPM physician office visits (mean [SD] 1.29 [± 0.95] vs. 2.02 [± 1.53], P < 0.001) and outpatient visits (mean [SD] 2.17 [± 2.90] vs. 3.52 [± 3.32], P < 0.001) compared with those in the warfarin group. There were no between-group differences in outcomes for the number of stroke, myocardial infarction, or bleeding-related office visits. All-cause medical costs for the dabigatran cohort were lower than the warfarin cohort; however, the difference did not reach statistical significance ($2,696 [SD ± $6,699] vs. $2,893 [± $6,819], P = 0.179). All-cause pharmacy costs were higher in the dabigatran group versus the warfarin group ($455 [± $429] vs. $328 [± $517], P < 0.001). The dabigatran cohort also had significantly higher stroke-related ($32 [± $71] vs. $20 [± $55], P = 0.006) and nonstroke-related pharmacy costs ($423 [± $422] vs. $308 [± $515], P < 0.001). Despite higher pharmacy costs for the dabigatran cohort, both treatment groups had statistically similar all-cause total costs ($3,151 [± $6,744] vs. $3,221 [± $6,869], P = 0.701).

CONCLUSIONS

This real-world study showed that among patients newly diagnosed with NVAF who were OAC naive, dabigatran use was associated with significantly less HCRU in terms of physician and outpatient visits but higher pharmaceutical costs in up to 12 months of follow-up. Similar to other real-world studies, this research supports the finding that higher pharmacy costs for dabigatran users was offset by lower medical costs, making total health care costs comparable between dabigatran and warfarin.

DISCLOSURES

This work was supported by Boehringer Ingelheim Pharmaceuticals, which is the manufacturer of dabigatran, one of the products included in the analysis of this work. The authors were responsible for all content and editorial decisions. Jain and Tan are employed by HealthCore, a research consultancy which was funded by Boehringer Ingelheim Pharmaceuticals for work on this study. Fu was employed by HealthCore at the time of this study. Lim, Wang, Elder, and Sander are employees of Boehringer Ingelheim Pharmaceuticals. Study concept and design were contributed by Wang, Sander, and Tan, along with Fu and Jain. Fu, Tan, and Jain collected the data, and data interpretation was performed by Lim, Wang, and Sander, along with Jain, Tan, and Fu. The manuscript was written by Jain, Elder, Tan, and Wang, along with Lim and Fu, and revised by Jain, Wang, Elder, and Tan. Some of the results of this study were presented at Quality of Care and Outcomes Research in Cardiovascular Disease and Stroke (QCOR) 2014 Scientific Sessions on June 2-4, 2014, in Baltimore, Maryland.

Outpatient Treatment of Deep Vein Thrombosis in the United States: The Reasons for Geographic and Racial Differences in Stroke Study

OBJECTIVE

To describe the uptake of outpatient DVT treatment in the United States and understand how comorbidities and socioeconomic conditions impact the decision to treat as an outpatient.

DESIGN/SETTING

The Reasons for Geographic and Racial Differences in Stroke cohort study recruited 30,329 participants between 2003 and 2007. DVT events were ascertained through 2011.

MEASUREMENTS

Multivariable logistic regression was used to determine the correlates of outpatient treatment of DVT accounting for age, sex, race, education, income, urban or rural residence, and region of residence.

RESULTS

Of 379 venous thromboembolism events, 141 participants had a DVT without diagnosed pulmonary embolism and that did not occur during hospitalization. Overall, 28% (39 of 141) of participants with DVT were treated as outpatients. In a multivariable model, the odds ratio for outpatient versus inpatient DVT treatment was 4.16 (95% confidence interval [CI], 1.25-13.79) for urban versus rural dwellers, 3.29 (95% CI, 1.30-8.30) for white versus black patients, 2.41 (95% CI, 1.06-5.47) for women versus men, and 1.90 (95% CI, 1.19-3.02) for every 10 years younger in age. Living outside the southeastern United States and having higher education and income were not statistically significantly associated with outpatient treatment.

CONCLUSIONS

Despite known safety and efficacy, only 28% of participants with DVT received outpatient treatment. This study highlights populations in which efforts could be made to reduce hospital admissions.

Deep Venous Thrombosis

Deep venous thrombosis (DVT) is a frequently encountered condition that is often diagnosed and treated in the outpatient setting. Risk stratification is helpful and recommended in the evaluation of DVT. An evidence-based diagnostic approach is discussed here. Once diagnosed, the mainstay of DVT treatment is anticoagulation. The specific type and duration of anticoagulation depend upon the suspected etiology of the venous thromboembolism, as well as risks of bleeding and other patient comorbidities. Both specific details and a standardized approach to this vast treatment landscape are presented.

Influence of a Commercial Antithrombotic Filter on the Caval Blood Flow During Neutra and Valsalva Maneuver

Anticoagulants are the treatment of choice for pulmonary embolism. When these fail or are contraindicated, vena cava filters are effective devices for preventing clots from the legs from migrating to the lung. Many uncertainties exist when a filter is inserted, especially during physiological activity such as normal breathing and the Valsalva maneuver. These activities are often connected with filter migration and vena cava damage due to the various related vein geometrical configurations. In this work, we analyzed the response of the vena cava during normal breathing and Valsalva maneuver, for a healthy vena cava and after insertion of a commercial Günther-Tulip® filter. Validated computational fluid dynamics (CFD) and patient specific data are used for analyzing blood flow inside the vena cava during these maneuvers. While during normal breathing, the vena cava flow can be considered almost stationary with a very low pressure gradient, during Valsalva the extravascular pressure compresses the vena cava resulting in a drastic reduction of the vein section, a global flow decrease through the cava but increasing the velocity magnitude. This change in the section is altered by the presence of the filter which forces the section of the vena cava before the renal veins to keep open. The effect of the presence of the filter is investigated during these maneuvers showing changes in wall shear stress and velocity patterns.

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

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

A post hoc analysis of dalteparin versus oral anticoagulant (VKA) therapy for the prevention of recurrent venous thromboembolism (rVTE) in patients with cancer and renal impairment

Venous thromboembolism (VTE) is a common and serious complication in patients with cancer; treatment guidelines recommend extended therapy of ≥6 months with low-molecular-weight heparin (LMWH) for treatment and prevention of recurrent VTE (rVTE) in this population. This post hoc analysis used data from the CLOT study—a phase III, randomized, open-label, controlled study (N = 676)—to compare the efficacy and safety of dalteparin, a LMWH, versus vitamin K antagonist (VKA) for prevention of rVTE in patients with cancer and renal impairment (creatinine clearance <60 ml/min). Overall, 162/676 (24 %) patients had renal impairment at baseline. Patients received subcutaneous dalteparin 200 IU/kg once daily during month 1, followed by 150 IU/kg once daily for months 2–6; or VKA once daily for 6 months, with initial overlapping subcutaneous dalteparin 200 IU/kg once daily for ≥5 days until international normalized ratio was 2.0–3.0 for 2 consecutive days. Endpoints included the rates of rVTE (primary) and bleeding events. Overall, fewer dalteparin-treated patients (2/74 [2.7 %]) experienced ≥1 adjudicated symptomatic rVTE compared with VKA-treated patients (15/88 [17.0 %]; hazard ratio = 0.15 [95 % confidence interval 0.03–0.65]; p = 0.01). Bleeding event rates for both treatments were similar (p = 0.47). In summary, compared with VKA, dalteparin significantly reduced risk of rVTE in patients with cancer and renal impairment (p = 0.01) while exhibiting a comparable safety profile. This analysis supports dosing patients with renal impairment in accordance with patients with normal renal function; however, anti-Xa monitoring could be considered to further support safety in selected patients, particularly those with very severe renal impairment.

Review of current evidence available for guiding optimal Enoxaparin prophylactic dosing strategies in obese patients-Actual Weight-based vs Fixed

BACKGROUND

The current debate over the optimal Enoxaparin prophylactic dosing strategies in obese patients centre around whether it should be based on the actual weight of the patient (i.e. weight-based), or at an artificially fixed amount, as it is the case in Australia (40mg daily). The vast majority of the evidence available today is laboratory-based, measuring serum Antifactor-X_a activities as a marker for physiological response.

AIM

The aim of the parent study is to compare the clinical outcomes for obese patients who received fixed doses of enoxaparin compared to those who received weight-based doses within the licensed dosage recommendations. This review was conducted to examine whether a gap in knowledge exists in relation to dosing obese patients with enoxaparin as VTE prophylaxis after hospital admission to aid in development of the parent study concept.

METHOD

Databases such as Medline, EBSCOhost, ProQuest were interrogated using combinations of words such as "enoxaparin", AND "dosing strategy", AND "obese/obesity" AND "prophylaxis". Only eleven out of 14 primary studies which were considered to be sufficiently similar in methodology and anticipated outcomes were reviewed and analysed.

RESULTS

Pooled data from the eleven studies suggested that weight-based or higher-than-fixed dosing had a 36.2% higher success rate than fixed dosing, and was more likely to achieve the desired serum Anti-X_a activity levels (52.2% and 16% respectively). The rate of failure to achieve this is significantly lower in the weight-based groups (13.3%) than in fixed-dose groups (18.5%). These eleven studies reviewed included 601 patients in total.

CONCLUSION

There is insufficient evidence to support or negate the current enoxaparin health outcomes in obese and very obese patients due to the lack of post-discharge follow-up from hospitals. Further research is required to compare long-term outcomes after fixed and weight-based dosing of enoxaparin. The optimal dose of enoxaparin per kilogram of body weight for prophylaxis remains to be determined.

The strong but nonspecific relationship between 18F-FDG uptake in the lower-extremity veins and venous thromboembolism

Venous thromboembolism (VTE) can present as deep vein thrombosis (DVT) and/or acute pulmonary embolism (PE). In fluorine-18 fluorodeoxyglucose (18F-FDG) PET/CT, 18F-FDG activity along the deep veins of the lower extremities (LE) is often observed and, unless it is associated with focal intense activity, is not considered abnormal. However, anecdotally it has been associated with the placement of an inferior vena cava filter. In this short paper we intend to investigate this association. We found 10 patients who were investigated in the vascular laboratory by means of either LE or upper-extremity duplex or a chest computed tomography with PE protocol, or who had undergone the placement of an inferior vena cava filter between 27 April 2010 and 7 January 2013 and who had also undergone one or more 18F-FDG-PET scan(s) that included the LE. Seventeen patients without venous 18F-FDG uptake were added as controls. 18F-FDG uptake visualized in the LE was scored as the number of positive LE veins and the extent of the radiotracer uptake. The time intervals between the VTE event and the 18F-FDG-PET scan(s) were recorded. The time intervals between the most remote and the closest 18F-FDG-PET before a VTE event averaged 79 ± 101 and 49 ± 82 days, respectively, and the closest and the most remote 18F-FDG-PET after the VTE event averaged 58 ± 50 and 122 ± 124 days. The extent of uptake in the LE veins averaged 7 ± 2 for the patients with an acute DVT on LE duplex and 5 ± 3 for those with negative or chronic DVT on LE duplex (P=nonsignificant). Two patients (n=3 and 10) were negative for VTE events and had an extent of 0. The number of positive events correlated slightly with the extent of venous uptake (r=0.69). The 17 control patients without venous uptake on 18F-FDG-PET had no history of VTE. There was an association between LE venous uptake of 18F-FDG and risk for VTE. The association was not related to the location of the VTE, nor to the timing of the VTE.

Validity of Criteria Used to Evaluate Fingerstick Devices That Assess International Normalized Ratio

Background . Investigators commonly rely on unvalidated, mainly arithmetic criteria to predict if point-of-care fingerstick devices that assess International Normalized Ratio (INR) lead to the same warfarin dosing decisions as a standard measure. Methods . Criteria that predict warfarin dosing agreement between 2 INR measurements were evaluated using clinicians’ actual dosing decisions as the standard. Bayesian hierarchical modeling was used to rank the criteria by the proportion of correct dosing predictions and the magnitude of difference between actual and predicted dosing agreement. Results . The prediction criteria misclassified dosing agreement for between 19% and 38% of paired INR values (x̄x: 27%). The magnitude of misclassification varied inconsistently throughout the INR scale. Conclusion . The unvalidated criteria used to predict warfarin dosing agreement between 2 INR measurements are associated with large error. Warfarin dosing decisions should be measured directly in such assessments.

Diagnosis and Treatment of Lower Extremity Deep Vein Thrombosis: Korean Practice Guidelines

Lower extremity deep vein thrombosis is a serious medical condition that can result in death or major disability due to pulmonary embolism or post-thrombotic syndrome. Appropriate diagnosis and treatment are required to improve symptoms and salvage the affected limb. Early thrombus clearance rapidly resolves symptoms related to venous obstruction, restores valve function and reduces the incidence of post-thrombotic syndrome. Recently, endovascular treatment has been established as a standard method for early thrombus removal. However, there are a variety of views regarding the indications and procedures among medical institutions and operators. Therefore, we intend to provide evidence-based guidelines for diagnosis and treatment of lower extremity deep vein thrombosis by multidisciplinary consensus. These guidelines are the result of a close collaboration between interventional radiologists and vascular surgeons. The goals of these guidelines are to improve treatment, to serve as a guide to the clinician, and consequently to contribute to public health care.

A Survey of Physicians' Knowledge and Management of Venous Thromboembolism

A review of all patients diagnosed with venous thromboembolism (VTE) at an academic medical center from 1996 to 1998 revealed a wide variation in management and subsequent patient outcomes and a 30% increase in utilization of the vascular laboratory from the previous 2-year period. The purpose of this study was to determine physicians' knowledge and management strategies before the implementation of integrated care pathways for VIE. Mail surveys were sent to 650 physicians covering 3 academic medical centers. The disciplines targeted were from those physicians who had previously referred patients for any VTE screening examination. One-hundred and twenty-eight physicians (20%) completed the survey. Only 12% of the physicians were able to correctly identify all of the veins routinely imaged as either deep or superficial veins. Fifty-nine percent of the physicians incorrectly identified the superficial femoral vein of the thigh as a superficial vein, and 23% believed the popliteal vein to be a superficial vein. Only 17% of the respondents correctly classified the tibial-peroneal veins as deep veins. Approximately 70% of the physicians stated that they would not treat symptomatic isolated calf vein thrombosis, and, of those, only 42% said that they would obtain serial duplex scans to monitor for proximal propagation. Physicians underestimated the charges for all diagnostic screening tests, and only 14% were able to correctly identify the range of charges for a venous duplex scan. This survey of physicians demonstrated a lack of basic knowledge regarding lower extremity venous anatomy, charges for the different diagnostic tests used to diagnose VIE, and, most importantly, current treatment standards for VTE.

Five-year follow-up of pulmonary embolism under anticoaugulation: The PISA-PEET (Pulmonary Embolism Extension Therapy) study

Benefits and harms of long-term anticoagulant therapy (AT) after acute pulmonary embolism (PE) are poorly known. The aim of this study was to investigate the outcome of patients with PE treated with AT for 5 years according to American College of Chest Physicians (ACCP) guidelines.Patients with both unprovoked and secondary PE were consecutively enrolled in a "real life" study. After a 12-month AT, they continued or stopped the treatment according to ACCP guidelines, and were followed-up for 5 years. Outcomes were all-cause mortality, recurrence, and fatal recurrence under AT.Of the original consecutive 585 patients, 471 were included (83 dead, 31 lost during the 1st year). Of these, 361 (76.6%) continued AT. During 5 years, death occurred in 109 (30.2%) patients, with a mortality rate of 8.00 events/100 person-years of follow-up; recurrence in 34 (9.4%), with an incidence rate of 2.58 events/person-years; fatal recurrence in 13 (3.6%), with an incidence rate of 0.95 events/person-years. The case fatality rate for recurrence was 38.2%. In the subgroup of patients with unprovoked PE, the chance of dying was significantly lower (RR 0.35; 95% confidence interval 0.24-0.53) and the tendency to fatal recurrence (not significantly) greater (0.11 events/100 person-years vs 0.07 events/100 person-years) than in the remaining patients. Major bleeding occurred in 5 (1.3%) patients. The case fatality rate for bleeding was 14.3%.During 5-year AT, 30% of patients dies, 10% experiences recurrences, and 5% has fatal recurrences. According to guidelines, most patients need to continue AT; the case fatality rate for bleeding is lower than that for recurrence.

Effects of Long-Term Low-Molecular-Weight Heparin on Fractures and Bone Density in Non-Pregnant Adults: A Systematic Review With Meta-Analysis

BACKGROUND

Adults who require long-term anticoagulation with low-molecular-weight heparin (LMWH) such as cancer patients or the elderly may be at increased risk of fractures.

OBJECTIVE

To determine the effects of LMWH therapy of at least 3 months' duration on fractures and bone mineral density (BMD) in non-pregnant adult populations.

METHODS

We systematically reviewed electronic databases (e.g., MEDLINE, EMBASE), conferences and bibliographies until June 2015 and included comparative studies in non-pregnant adult populations that examined the effects of LMWH (≥3 months) on fractures and BMD. We synthesized evidence qualitatively and used random-effects meta-analysis to quantify the effect of LMWH on fractures.

RESULTS

Sixteen articles reporting 14 studies were included: 10 clinical trials (n = 4865 participants) and four observational cohort studies (3 prospective, n = 221; 1 retrospective, n = 30). BMD and fractures were secondary outcomes in the majority of trials, while they were primary outcomes in the majority of observational studies. In participants with venous thromboembolism and underlying cardiovascular disease or cancer (5 RCTs, n = 2280), LMWH for 3-6 months did not increase the relative risk of all fractures at 6-12 months compared to unfractionated heparin, oral vitamin K antagonists or placebo [pooled risk ratio (RR) = 0.58, 95 % CI: 0.23-1.43; I(2) = 12.5 %]. No statistically significant increase in the risk of fractures at 6-12 months was found for cancer patients (RR = 1.08, 95 % CI: 0.31-3.75; I(2) = 4.4 %). Based on the data from two prospective cohort studies (n = 166), LMWH for 3-24 months decreased mean BMD by 2.8-4.8 % (depending on the BMD site) compared to mean BMD decreases of 1.2-2.5 % with oral vitamin K antagonists.

CONCLUSIONS

LMWH for 3-6 months may not increase the risk of fractures, but longer exposure for up to 24 months may adversely affect BMD. Clinicians should consider monitoring BMD in adults on long-term LMWH who are at increased risk of bone loss or fracture.

Therapeutic Update on the Prevention and Treatment of Venous Thromboembolism

Venous thromboembolism (VTE) is a common condition that increases in incidence with age and risk factors. Therapies for VTE are aimed at either preventing the disease in high-risk individuals or treating patients who have developed VTE. Assessing risk and aggressively using the recommended therapies is primacy in preventing VTE in surgical and medical patients. Risk of VTE in medical patients has become more defined in recent years, and prophylaxis in this group can prevent scores of iatrogenic VTE. Treatment of VTE has evolved in the past decade from a condition that required hospitalization for 5 to 7 days to a disease state that can be conveniently and safely treated on an outpatient basis, largely due to the advent of low-molecular-weight heparins and patient self-directed treatment.

Low-Molecular-Weight Heparin for the Treatment of Venous Thromboembolism in the Elderly

Venous thromboembolism (deep vein thrombosis and/or pulmonary embolism) is a common problem in the elderly population. Indeed, increasing age is a significant risk factor for venous thromboembolism. The treatment of venous thromboembolism in the elderly population presents certain unique problems related to aging, such as decreasing body weight, increasing renal insufficiency and numerous comorbid conditions, which complicate therapy. Treatment of venous thromboembolism in the elderly has been complicated by an increased incidence of bleeding, particularly with the use of warfarin. The risk of bleeding may be substantially reduced by carefully adjusting the warfarin dose to maintain a therapeutic INR and for this purpose anticoagulant management clinics have been shown to be useful. The low-molecular-weight heparins have been shown to be efficacious and safe for the treatment of venous thromboembolism in several clinical trials, including many patients in the older age brackets. Furthermore, these agents can safely be used in the out-of-hospital setting. Long-term use of low-molecular-weight heparin is an alternative to the use of oral anticoagulant therapy, particularly in patients with cancer or recurrent venous thromboembolism.

A Nurse-Led Ambulatory Care Pathway for Patients With Deep Venous Thrombosis in an Acute Teaching Hospital

This article describes the management of deep vein thrombosis (DVT) using an ambulatory nurse-led pathway and the compression technique using duplex ultrasound. This pathway permits the management of the “walking wounded” as well as other patients at varying risks of having DVT and in so doing has changed the approach toward the management of this common clinical event. The success of the described pathway is attributed to the development of low molecular weight heparin and the reliability of diagnostics.

Meta-analysis and suggested guidelines for prevention of venous thromboembolism (VTE) in foot and ankle surgery

PURPOSE

To perform a meta-analysis investigating venous thromboembolism (VTE) following isolated foot and ankle surgery and propose guidelines for VTE prevention in this group of patients.

METHODS

Following a PRISMA compliant search, 372 papers were identified and meta-analysis performed on 22 papers using the Critical Appraisal Skills Programme and Centre for Evidence-Based Medicine level of evidence.

RESULTS

43,381 patients were clinically assessed for VTE and the incidence with and without chemoprophylaxis was 0.6% (95% CI 0.4-0.8%) and 1% (95% CI 0.2-1.7%), respectively. 1666 Patients were assessed radiologically and the incidence of VTE with and without chemoprophylaxis was 12.5% (95% CI 6.8-18.2%) and 10.5% (95% CI 5.0-15.9%), respectively. There was no significant difference in the rates of VTE with or without chemoprophylaxis whether assessed clinically or by radiological criteria. The risk of VTE in those patients with Achilles tendon rupture was greater with a clinical incidence of 7% (95% CI 5.5-8.5%) and radiological incidence of 35.3% (95% CI 26.4-44.3%).

CONCLUSION

Isolated foot and ankle surgery has a lower incidence of clinically apparent VTE when compared to general lower limb procedures, and this rate is not significantly reduced using low molecular weight heparin. The incidence of VTE following Achilles tendon rupture is high whether treated surgically or conservatively. With the exception of those with Achilles tendon rupture, routine use of chemical VTE prophylaxis is not justified in those undergoing isolated foot and ankle surgery, but patient-specific risk factors for VTE should be used to assess patients individually.

LEVEL OF EVIDENCE

II.

Guidance for the practical management of the heparin anticoagulants in the treatment of venous thromboembolism

Venous thromboembolism (VTE) is a serious and often fatal medical condition with an increasing incidence. Despite the changing landscape of VTE treatment with the introduction of the new direct oral anticoagulants many uncertainties remain regarding the optimal use of traditional parenteral agents. This manuscript, initiated by the Anticoagulation Forum, provides clinical guidance based on existing guidelines and consensus expert opinion where guidelines are lacking. This specific chapter addresses the practical management of heparins including low molecular weight heparins and fondaparinux. For each anticoagulant a list of the most common practice related questions were created. Each question was addressed using a brief focused literature review followed by a multidisciplinary consensus guidance recommendation. Issues addressed included initial anticoagulant dosing recommendations, recommended baseline laboratory monitoring, managing dose adjustments, evidence to support a relationship between laboratory tests and meaningful clinical outcomes, special patient populations including extremes of weight and renal impairment, duration of necessary parenteral therapy during the transition to oral therapy, candidates for outpatient treatment where appropriate and management of over-anticoagulation and adverse effects including bleeding and heparin induced thrombocytopenia. This article concludes with a concise table of clinical management questions and guidance recommendations to provide a quick reference for the practical management of heparin, low molecular weight heparin and fondaparinux.

Neurologically normal survival after fibrinolysis during prolonged cardiac arrest: case report and discussion

Cardiac arrest secondary to pulmonary embolism is a devastating condition with a high mortality rate. It is currently unclear whether fibrinolysis (thrombolysis) is beneficial in this setting. We report the case of a 28-year-old woman with a pulmonary embolism who developed return of pulses following the administration of tissue plasminogen activator after 38 minutes of pulseless electrical activity cardiac arrest. She went on to make a full neurologic and cardiopulmonary recovery. This case is discussed with reference to the current literature on the subject.

The hypercoagulable states in anaesthesia and critical care

Hypercoagulable disorders are now diagnosed more frequently than before. These patients are, usually, managed with multiple anticoagulant and antiplatelet medications. Left unmonitored and unevaluated, there can be disastrous haemorrhagic or thrombotic complications. Appropriate perioperative and anaesthetic management of these patients will invite an aetiological diagnosis, severity analysis and the on-going treatment review. Different assays, thromboelastography and molecular cytogenetics have helped to diagnose these conditions precisely and thus guide the long-term management. Besides this, there are varieties of clinical conditions that will predispose to the hypercoagulability. These need to be defined and classified in order to offer a suitable therapeutic option. Pregnancy is one such important condition and can have more than one responsible factor favouring hypercoagulability. With such diverse kinds of disorders, it would be essential to note the anaesthetic implications, to avoid adverse perioperative outcomes. Available evidence based guidelines will help to make the therapeutic approach more precise. Selection of the appropriate technique of anaesthesia, offering the appropriate anticoagulation bridging as necessary and defining an appropriate interval and time for the intervention will help to minimise the complications.

Pharmacogenetic-guided dosing of coumarin anticoagulants: algorithms for warfarin, acenocoumarol and phenprocoumon

Coumarin derivatives, such as warfarin, acenocoumarol and phenprocoumon are frequently prescribed oral anticoagulants to treat and prevent thromboembolism. Because there is a large inter-individual and intra-individual variability in dose-response and a small therapeutic window, treatment with coumarin derivatives is challenging. Certain polymorphisms in CYP2C9 and VKORC1 are associated with lower dose requirements and a higher risk of bleeding. In this review we describe the use of different coumarin derivatives, pharmacokinetic characteristics of these drugs and differences amongst the coumarins. We also describe the current clinical challenges and the role of pharmacogenetic factors. These genetic factors are used to develop dosing algorithms and can be used to predict the right coumarin dose. The effectiveness of this new dosing strategy is currently being investigated in clinical trials.

Evaluation of GenoFlow Thrombophilia Array Test Kit in its detection of mutations in Factor V Leiden (G1691A), prothrombin G20210A, MTHFR C677T and A1298C in blood samples from 113 Turkish female patients

Thrombophilia is a heritable blood disease characterized by an increased tendency to form abnormal blood clots that can block blood vessels. In obstetrics and gynecology, it has been shown by a number of reports that a proportion of recurrent miscarriages involve thrombophilia-related mutations, in particular, Factor V G1691A, prothrombin G20210A, and MTHFR C677T and A1298C. In this study, we examined the frequency of these four mutations in 113 female Turkish patients who had prior complications in pregnancy, using the DiagCor GenoFlow Thrombophilia Array Test kit. Heterozygous MTHFR C677T and A1298C mutations were detected in 46% of the patients, and among these patients, 60% of them carried double heterozygous mutations. In contrast, the heterozygous Factor V G1691A and prothrombin G20210A were detected only in a smaller number of patients, respectively, 13% and 3%. The GenoFlow kit demonstrated 100% concordance with results from Sanger sequencing, which can be translated into sensitivity and specificity both at 100% within this series of patients.

A New Frontier: Integrating Behavioral and Digital Technology to Promote Health Behavior

Modifiable behavioral risk factors such as cigarette smoking, physical inactivity, and obesity contribute to over 40 % of premature deaths in the USA. Advances in digital and information technology are creating unprecedented opportunities for behavior analysts to assess and modify these risk factors. Technological advances include mobile devices, wearable sensors, biomarker detectors, and real-time access to therapeutic support via information technology. Integrating these advances with behavioral technology in the form of conceptually systematic principles and procedures could usher in a new generation of effective and scalable behavioral interventions targeting health behavior. In this selective review of the literature, we discuss how technological tools can assess and modify a range of antecedents and consequences of healthy and unhealthy behavior. We also describe practical, methodological, and conceptual advantages for behavior analysts that stem from the use of technology to assess and treat health behavior.

Guidelines for the prevention of stroke in patients with stroke and transient ischemic attack: a guideline for healthcare professionals from the American Heart Association/American Stroke Association

The aim of this updated guideline is to provide comprehensive and timely evidence-based recommendations on the prevention of future stroke among survivors of ischemic stroke or transient ischemic attack. The guideline is addressed to all clinicians who manage secondary prevention for these patients. Evidence-based recommendations are provided for control of risk factors, intervention for vascular obstruction, antithrombotic therapy for cardioembolism, and antiplatelet therapy for noncardioembolic stroke. Recommendations are also provided for the prevention of recurrent stroke in a variety of specific circumstances, including aortic arch atherosclerosis, arterial dissection, patent foramen ovale, hyperhomocysteinemia, hypercoagulable states, antiphospholipid antibody syndrome, sickle cell disease, cerebral venous sinus thrombosis, and pregnancy. Special sections address use of antithrombotic and anticoagulation therapy after an intracranial hemorrhage and implementation of guidelines.

Dehydration is an independent predictor of discharge outcome and admission cost in acute ischaemic stroke

BACKGROUND AND PURPOSE

Our aim was to investigate the influence of admission dehydration on the discharge outcome in acute ischaemic and hemorrhagic stroke.

METHODS

Between January 2009 and December 2011, 4311 ischaemic and 1371 hemorrhagic stroke patients from the stroke registry of Chang Gung healthcare system were analyzed. The eligible patients were identified according to inclusion/exclusion criteria. In total, 2570 acute ischaemic and 573 acute hemorrhagic stroke patients were finally recruited. According to the blood urea nitrogen (BUN) to creatinine (Cr) ratio (BUN/Cr), these patients were divided into dehydrated (BUN/Cr ≥ 15) and non-dehydrated (BUN/Cr < 15) groups. Demographics, admission costs and discharge outcomes including modified Rankin scale (mRS) and Barthel index (BI) were examined. Data were analyzed using multivariate analysis of two-stage least squares including logistic and linear regression.

RESULTS

Acute ischaemic stroke with admission dehydration had higher infection rates (P = 0.006), worse discharge BI (62.8 ± 37.4 vs. 73.4 ± 32.4, P < 0.001, adjusted P < 0.001), worse mRS (2.7 ± 1.6 vs. 2.3 ± 1.5, P < 0.001, adjusted P = 0.009) and higher admission costs (2470.8 ± 3160.8 vs. 1901.2 ± 2046.8 US dollars, P < 0.001, adjusted P = 0.013) than those without dehydration. However, acute hemorrhagic stroke with or without admission dehydration showd no difference in admission costs (P = 0.618) and discharge outcomes (BI, P = 0.058; mRS, P = 0.058).

CONCLUSION

Admission dehydration is associated with worse discharge outcomes and higher admission costs in acute ischaemic stroke but not in hemorrhagic stroke.

Thrombolytic and anticoagulant therapy for acute submassive pulmonary embolism

This study aimed to compare the efficacy and safety of thrombolytic and anticoagulant therapy for acute submassive pulmonary embolism (PE). A retrospective evaluation was performed on 25 consecutive inpatients with acute submassive PE treated by thrombolytic therapy and 25 earlier consecutive inpatients with acute submassive PE treated by anticoagulant therapy. No statistically significant difference in clinical curative effect was identified between the thrombolysis and anticoagulation groups (P>0.05). Following 24 h of therapy, the improvement rates of dyspnea and revascularization in the thrombolysis group achieved statistical significance compared with those of the anticoagulation group (P<0.01 for each). The PO₂ level of the thrombolysis group (81.18±5.66 mmHg) was notably higher than that of the anticoagulation group and the difference was statistically significant (P<0.01). The pulmonary arterial pressures of the thrombolysis group (51.21±6.86 mmHg) were significantly lower than those of the anticoagulation group (60.64±5.17 mmHg) (P<0.01). Furthermore, the difference between the hemorrhage rates of the two groups was statistically significant (P<0.05). Thrombolysis was shown to rapidly relieve dyspnea, reduce pulmonary arterial pressure and revascularize the embolized blood vessels. However, the hemorrhage rate of the thrombolysis group was higher than that of the anticoagulation group. The overall efficacies and fatality rates of the thrombolysis and anticoagulation groups were similar.

Low-molecular-weight heparin for anti-coagulation after left ventricular assist device implantation

BACKGROUND

Anti-coagulation is required in patients with left ventricular assist devices (LVADs). We evaluated the feasibility of low-molecular-weight heparin (LMWH) for initiation of anti-coagulation and transitioning to oral anti-coagulation after LVAD implantation.

METHODS

This single-center study included 78 consecutive patients who underwent either Thoratec HeartMate II LVAD (n = 27) or HeartWare ventricular assist device (HVAD, n = 51) implantation. The LMWHs enoxaparin (n = 50) and dalteparin (n = 28) were used. LMWH was started within 24 hours post-operatively in 79.5% of patients. No anti-coagulation was given before starting LMWH therapy. LMWH activity was monitored by determination of anti-factor Xa levels in plasma.

RESULTS

The majority of patients (80.7%) had peak anti-Xa activity within the defined range of efficacy of 0.2 to 0.4 IU/ml by the second day of treatment. Mean effective peak anti-Xa activity was 0.28 ± 0.06 IU/ml. Mean duration of anti-coagulation with LMWH was 25.8 ± 18 days. Ischemic strokes were observed in 3 patients (3.8%), with a total of 4 events. Three events occurred while on LMWH, and 1 event occurred during follow-up on oral anti-coagulation. There was 1 fatal stroke. No pump thrombus was observed. Major bleeding was observed in 5 patients (6.4%), with a total of 6 events. Gastrointestinal bleeding was the most common complication (n = 3). There were no fatal bleeding events.

CONCLUSIONS

LMWH in the setting of LVAD shows rapid and constant biologic efficacy. Anti-coagulation with LMWH appears feasible after LVAD implantation. These findings support further evaluation of LMWH as an alternative to unfractionated heparin in this patient cohort.

Respiratory review of 2013: pulmonary thromboembolism

Pulmonary embolism (PE), which can originate as a consequence of deep vein thrombosis (DVT), is the most frequent and potentially fatal venous thromboembolic event. Despite the fact that the incidence of venous thromboembolism (VTE) in Asians is lower than that in the Western populations, a recent epidemiologic study demonstrates an increasing incidence of VTE in the Korean population. Anticoagulants, including low molecular weight heparin (LMWH) and vitamin K antagonist (VKAs), have been the main treatments for PE, however, recently new oral anticoagulants (NOACs) were introduced. We will review how well patients with PE can be managed with the existing anticoagulants and NOACs along with the time span of treatment, which still pose some challenges for clinicians.

Bilateral upper-extremity deep vein thrombosis following central cord syndrome

Deep vein thrombosis (DVT) is a common complication following spinal cord injury (SCI). Although DVT of the upper extremity is much less common than DVT of the lower extremities, the risk of pulmonary embolism following upper-extremity DVT should not be disregarded.

METHOD

Case report.

FINDINGS

A bilateral upper-extremity DVT developed in a 51-year-old woman with SCI (central cord syndrome) being followed in our rehabilitation clinic. Medical treatment resulted in improvement in the clinical status of the patient as well as the regression in the thrombus.

CONCLUSION

In patients with SCI, DVT should be kept in mind in the presence of pain and edema in the upper extremities, and prophylactic DVT treatment should be considered.