Treatment algorithm in cancer-associated thrombosis: Canadian expert consensus

Management of anticoagulant therapy for the treatment of venous thromboembolism (vte) in cancer patients is complex because of an increased risk of recurrent vte and major bleeding complications in those patients relative to the general population. Subgroups of patients with cancer also show variation in their risk for recurrent vte and adverse bleeding events. Accordingly, a committee of 10 Canadian clinical experts developed the consensus risk- stratification treatment algorithm presented here to provide guidance on tailoring anticoagulant treatment choices for the acute and extended treatment of symptomatic and incidental vte, to prevent recurrent vte, and to minimize the bleeding risk in patients with cancer. During a 1-day live meeting, a systematic review of the literature was performed, and a draft treatment algorithm was developed. The treatment algorithm was refined through the use of a Web-based platform and a series of online teleconferences. Clinicians using this treatment algorithm should consider the bleeding risk, the type of cancer, and the potential for drug-drug interactions in addition to informed patient preference in determining the most appropriate treatment for patients with cancer-associated thrombosis. Anticoagulant therapy should be regularly reassessed as the patient's cancer status and management change over time.

McMaster RARE-Bestpractices clinical practice guideline on diagnosis and management of the catastrophic antiphospholipid syndrome

Background The McMaster RARE-Bestpractices project group selected the catastrophic antiphospholipid syndrome (CAPS) for a pilot exercise in guideline development for a rare disease. Objectives The objectives of this exercise were to provide a proof of principle that guidelines can be developed for rare diseases and assist in clinical decision making for CAPS. Patients/Methods The GIN-McMaster Guideline Development checklist and GRADE methodology were followed throughout the guideline process. The CAPS guideline was coordinated by a steering committee, and the guideline panel was formed with representation from all relevant stakeholder groups. Systematic reviews were performed for the key questions. To supplement the published evidence, we piloted novel methods, including use of an expert-based evidence elicitation process and ad hoc analysis of registry data. Results This paper describes the CAPS guideline recommendations, including evidence appraisal and discussion of special circumstances and implementation barriers identified by the panel. Many of these recommendations are conditional, because of subgroup considerations in this heterogeneous disease, as well as variability in patient values and preferences. Conclusions The CAPS clinical practice guideline initiative met the objective of the successful development of a clinical practice guideline in a rare disease using GRADE methodology. We expect that clinicians caring for patients with suspected CAPS will find the guideline useful in assisting with diagnosis and management of this rare disease.

Risk stratification for the development of venous thromboembolism in hospitalized patients with cancer

Essentials The Khorana score is validated for risk of venous thromboembolism (VTE) in cancer outpatients. We conducted a multicenter analysis of medically hospitalized cancer patients. Patients with a higher Khorana score on admission were more likely to develop VTE. The Khorana score is predictive of in-hospital, symptomatic VTE development.

SUMMARY

Introduction The Khorana score is a validated risk assessment score for estimating the risk of symptomatic venous thromboembolism (VTE) in outpatients with cancer. The objective of this study was to assess the Khorana score for predicting the development of VTE in cancer patients during hospital admission. Methods We conducted an analysis of consecutive, adult cancer patients hospitalized for medical reasons between January and June 2010 in three academic medical centers. Information on objectively diagnosed, symptomatic VTE during hospitalization, use of anticoagulant thromboprophylaxis (TP) and Khorana score variables at the time of admission was collected. Results A total of 1398 patients were included. Mean age was 62 years, 51.2% were male, and mean BMI was 25.9 kg m-2 . The most frequent reasons for hospitalization were chemotherapy administration (22.3%), followed by pain control and palliation (21.4%). The overall incidence of VTE was 2.9% (95% CI, 2.0-3.8%), occurring in 5.4% (95% CI, 1.9-8.9%) of the high-, 3.2% (95% CI, 2.0-4.4%) of the intermediate- and 1.4% (95% CI, 0.3-2.6%), of the low-risk groups. High-risk patients were more likely than low-risk patients to have VTE (OR, 3.9; 95% CI, 1.4-11.2). Conclusion The Khorana score is predictive of in-hospital, symptomatic VTE development in cancer patients who are hospitalized for medical reasons and may be a useful tool for tailoring inpatient anticoagulant thromboprophylaxis.

Association between remote major venous thromboembolism risk factors and the risk of recurrence after a first unprovoked episode

Essentials Is remote exposure to major venous thromboembolism (VTE) risk factor related to lower recurrence? We analyzed data from the REVERSE study, a cohort of patients with no recent major risk factor. We found no association between remote risk factors and the risk of recurrence. Patients with remote VTE risk factor should be managed as having had an unprovoked VTE.

SUMMARY

Background It has been shown that the risk of recurrence of venous thromboembolism (VTE) is significantly lower when provoked by a major risk factor such as surgery or trauma compared with an event that was unprovoked. Objectives In this study we aimed to assess the association between remote exposure (3-12 months prior to VTE) to major VTE risk factors and the risk of recurrent VTE. Methods This was a post-hoc analysis of the REVERSE study, a prospective cohort of 646 patients with a first VTE, not provoked by a recent (< 3 months) major risk factor. Results We found no difference in the recurrence rate in patients with or without remote exposure to major VTE risk factors, including immobilization (hazard-ratio [HR], 1.4; 95% confidence interval, 0.7-2.6), surgery (HR, 0.8; 0.3-1.9) and trauma (HR, 1.3; 0.5-3.6). Conclusion None of the tested risk factors were associated with a lower risk of recurrence during follow-up. Patients with remote exposure to major risk factors at the time of a first VTE should not be managed differently from patients with no VTE risk factors.

Thrombotic and bleeding outcomes following perioperative interruption of direct oral anticoagulants in patients with venous thromboembolic disease

Essentials Studies evaluating the procedural interruption of direct oral anticoagulants (DOACs) are lacking. We conducted a study of the interruption of DOACs for prior venous thromboembolic disease (VTE). The post-operative risks of recurrent VTE and major bleeding are low in this patient population. A scheme based on half-life and procedure-related bleeding appears safe and efficacious.

SUMMARY

Background Direct oral anticoagulants (DOACs) are increasingly being used in the setting of venous thromboembolic disease (VTE). There is little evidence to guide the peri-procedural interruption of DOACs in this patient population. A number of studies have evaluated the perioperative interruption of DOACs based on half-life of the anticoagulant and the underlying procedural bleeding risk in patient with atrial fibrillation, but it remains unclear whether these findings can be extended to patients with VTE. Objective Evaluate thrombotic and bleeding outcomes following the perioperative interruption of direct oral anticoagulation in patients with prior VTE. Methods We conducted a retrospective analysis of consecutive patients on a DOAC for prior VTE requiring temporary interruption of anticoagulation for an invasive procedure. The primary efficacy outcome was the 30-day symptomatic VTE rate, and the primary safety outcome was the 30-day major bleeding rate. Secondary outcomes included overall mortality and the rate of clinically relevant non-major bleeding. Results A total of 190 patients were included in the analysis. The 30-day VTE rate was 1.05% (95% CI, 0.29-3.8%) and the 30-day major bleeding rate was 0.53% (95% CI, 0.09-2.93%). There were no deaths during the 30-day follow-up period. The rate of clinically relevant non-major bleeding was 3.16% (95%CI , 1.46-6.72%). Conclusions The perioperative interruption of DOACs in the setting of VTE, using a strategy that considers the half-life of the DOAC and the underlying procedural bleeding risk, appears to be both safe and effective.

Net clinical benefit of hospitalization versus outpatient management of patients with acute pulmonary embolism

Essentials Clinical benefit of hospitalization vs. outpatient treatment in pulmonary embolism (PE) is unknown. We performed a propensity matched cohort study of hemodynamically stable PE patients. Regardless of the risk assessment, hospitalized patients had the highest rate of adverse event. If confirmed, ambulatory care of normotensive PE patients may be preferred whenever possible.

SUMMARY

Background The decision to hospitalize or not patients with acute pulmonary embolism (PE) is controversial. Despite the advantages of close monitoring, hospitalization by itself may lead to in-hospital complications and potentially worsen the prognosis of PE patients. Objectives To determine the net clinical benefit of hospitalization vs. outpatient management of normotensive patients with acute pulmonary embolism (PE). Methods Retrospective cohort propensity score analysis (radius marching with replacement). Hemodynamically stable PE patients treated as outpatients or inpatients were matched to balance out differences for 28 patient characteristics and known risk factors for adverse events. The primary outcome was the rate of adverse events at 14 days, including recurrent venous thromboembolism, major bleeding or death. Results Among 1127 eligible patients, 1081 were included in the matched cohort, 576 treated as inpatients and 505 as outpatients. The 14-day rate of adverse events was 13.0% for inpatients and 3.3% for outpatients (adjusted OR, 5.07; 95% CI, 1.68-15.28). The 3-month rate was 21.7% for inpatients and 6.9% for outpatients (OR, 4.90; 95% CI, 2.62-9.17). In the high-risk subgroup (Pulmonary Embolism Severity Index class III-V; n = 597), the 14-day rate of adverse events was 16.5% for hospitalized patients vs. 4.5% for outpatients (OR, 4.16; 95% CI, 1.2-14.35). Conclusion Outpatient treatment of hemodynamically stable PE patients seems to be associated with a lower rate of adverse events than hospitalization and, if confirmed, may be considered as first-line management in patients not requiring specific in-hospital care, regardless of their initial risk stratification, if proper outpatient care can be provided.

Performance of the age-adjusted cut-off for D-dimer in patients with cancer and suspected pulmonary embolism

BACKGROUND

Cancer patients frequently present with suspected pulmonary embolism (PE). The D-dimer (DD) test is less useful in excluding PE in cancer patients due to the lower specificity. In the general population, the age-adjusted cutoff for DD combined with a clinical decision rule (CDR) improved specificity in the diagnosis of PE.

OBJECTIVES

To evaluate the safety and efficacy of the age-adjusted cutoff (defined as age∗10μg/L in patients >50years) combined with a CDR for the exclusion of PE in cancer patients.

METHODS

We conducted a prospective study to evaluate the age-adjusted cutoff in patients with suspected PE. Here we report a post-hoc analysis on the performance of the age-adjusted cutoff in patients with and without cancer. The primary outcome was the rate of venous thromboembolic events (VTE) during three-month follow-up.

RESULTS

Of 3324 patients with suspected PE, 429 (12.9%) patients had cancer. The prevalence of PE was 25.2% in cancer patients and 18% in patients without cancer (p<0.001). Among cancer patients with an unlikely CDR, 9.9% had a DD <500μg/L as compared with 19.7% using the age-adjusted cutoff. In patients without cancer, these rates were 30.1% and 41.9%. The proportion of cancer patients in whom PE could be excluded by CDR and DD doubled from 6.3% to 12.6%. No VTE occurred during three-month follow-up (failure rate 0.0% (95% CI 0.0-6.9%)).

CONCLUSION

Compared with the conventional cutoff, the age-adjusted D-dimer cutoff doubles the proportion of patients with cancer in whom PE can be safely excluded by CDR and DD without imaging.

Inferior vena cava filters

Use of inferior vena cava (IVC) filters has increased dramatically in recent decades, despite a lack of evidence that their use has impacted venous thromboembolism (VTE)-related mortality. This increased use appears to be primarily driven by the insertion of retrievable filters for prophylactic indications. A growing body of evidence, however, suggests that IVC filters are frequently associated with clinically important adverse events, prompting a closer look at their role. We sought to narratively review the current evidence on the efficacy and safety of IVC filter placements. Inferior vena cava filters remain the only treatment option for patients with an acute (within 2-4 weeks) proximal deep vein thrombosis (DVT) or pulmonary embolism and an absolute contraindication to anticoagulation. In such patients, anticoagulation should be resumed and IVC filters removed as soon as the contraindication has passed. For all other indications, there is insufficient evidence to support the use of IVC filters and high-quality trials are required. In patients where an IVC filter remains, regular follow-up to reassess removal and screen for filter-related complications should occur.