Abstract Background: Parenteral anticoagulants may improve outcomes in patients with cancer by reducing the risk of venous thromboembolism (VTE) and through a direct anti-tumour effect. Study-level meta-analysis indicates a reduction in VTE and provide moderate certainty that a small survival benefit exists; it is unclear if patients with specific cancers benefit more or less. Utilizing data from randomized controlled trials (RCT), this individual participant data meta-analysis examines the impact of heparin on survival, VTE and major bleeding in oncological patients randomized to low-molecular weight heparin (LMWH) or no LMWH. Methods: We performed a comprehensive systematic search for all RCTS (last search date March 2017) and contacted authors and sponsors to obtain individual participant data of patients with solid cancers and no other indication for prophylactic or therapeutic anticoagulation. We utilized the GRADE approach to evaluate the certainty of evidence and produce an evidence profile. All analyses followed the intention-to-treat principle. We calculated the impact on mortality through multivariable hierarchical models with patient-level variables as fixed effects and a categorical trial variable as a random effect. We adjusted the analysis for age, cancer type and metastasis status. To investigate whether intervention effects vary by predefined subgroups, including type of cancer, we tested interaction terms in the statistical model. Results: A total of 18 RCTs (n=10,041 participants) were eligible for inclusion and we obtained data from 82.4% of the participants (13 RCTs, n=8,278; n=4,139 for LMWH and n=4,139 for no LMWH). The meta-analysis revealed an adjusted relative risk of mortality within one year of 0.99 (95% CI: 0.95, 1.03) and a hazard ratio of 0.97 (95% CI: 0.82, 1.14) after one year. The relative risk for VTE was 0.58 (95% CI: 0.48, 0.71), 0.57 (95% CI: 0.44, 0.74) for symptomatic deep vein thrombosis and 0.58 (95%CI: 0.44, 0.77) for symptomatic pulmonary embolism, separately. For every 1,000 patients treated, approximately 16 fewer would experience symptomatic DVT and 16 fewer would experience any PE. The adjusted relative risk for major bleeding throughout trial duration was 1.24 (95% CI: 0.91, 1.69; P=0.17). Subgroup analysis, by cancer type, of VTE occurrence throughout trial duration identified lung cancer OR=0.52 (95% CI: 0.39, 0.68; P<0.001) and pancreatic cancer OR=0.55 (95% CI: 0.35, 0.88; P=0.01) patients as experiencing the greatest benefit from LMWH treatment. The certainty of the evidence for the outcomes was moderate to high. Conclusion: LMWH reduces risk of VTE without increasing risk of bleeding but does not improve survival across all patients. Funding: Canadian Institutes of Health Research knowledge synthesis grant, KRS 126594 Registration: International Prospective Register for Systematic Reviews (PROSPERO), CRD42013003526. Disclosures Schünemann: Canadian Institutes of Health Research: Research Funding. Crowther: Alexion: Speakers Bureau; Bayer: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Boehringer Ingelheim: Speakers Bureau; Leo Pharma: Research Funding; Pfizer: Honoraria; Portola: Consultancy; Shinogi: Consultancy. Macbeth: Pfizer: Other: Provision of Dalteparin for FRAGMATIC trial; Cancer Research UK: Research Funding. Griffiths: Pfizer: Consultancy, Other: Comment: I run an academic clinical trials unit, have received educational/investigator intiated research grants from companies that make these heparin agents. As consultant > 3 years ago, advised Pfizer on clinical trial designs unrelated to this study., Research Funding. Van Es: Pfizer: Employment, Other: Comment: Dr. van Es reports personal fees from Pfizer as a member of their advisory board. These fees are unrelated to this project.. Streiff: Roche: Research Funding; Portola: Research Funding; Janssen Scientific Affairs, LLC: Consultancy, Research Funding; CSL Behring: Consultancy, Research Funding. Ageno: BMS-Pfizer: Consultancy, Honoraria; Bayer AG: Consultancy, Honoraria, Research Funding; Boehringer Ingelheim: Consultancy, Honoraria; Daiichi Sankyo: Consultancy, Honoraria. Bozas: PharmaMar: Honoraria. McBane: Bristol Myers Squibb: Other: Research grant for cancer associated VTE. Maraveyas: Bayer: Other: Personal fees and conference attendance; Bristol-Myers Squibb: Other: Grants and personal fees; Leo Pharma: Other: Grants, personal fees and conference attendance; Pfizer: Other: Personal fees. Loprinzi: Bristol Myers: Other: Grant - unrelated to this project; Janssen: Other: Grant - unrelated to this project.
Reduced calf muscle pump function is a risk factor for venous thromboembolism: a population-based cohort study
Abstract The calf muscle pump is a major determinate of venous return in the legs but has not been studied as a risk factor for venous thromboembolism (VTE). A population-based cohort study of Olmsted County, Minnesota residents was performed using calf pump function (CPF) measurements from venous plethysmography studies from 1998 to 2015. Patients with a history of VTE were excluded. Nursing validated VTE outcomes from the Rochester Epidemiology Project were identified after the index study date, and patients with reduced CPF (rCPF) were compared with patients with normal CPF. A total of 1532 patients with recorded CPF (28% air and 72% strain gauge plethysmography) were included; 591 (38.5%) had normal CPF, 353 (23.0%) had unilateral rCPF, and 588 (38.3%) had bilateral rCPF. Any VTE occurred in 87 patients (5.7%) after a median follow-up of 11.7 years (range, 0-22.0 years). Comparing patients with bilateral reduced to bilateral normal CPF, the unadjusted hazard ratio (HR) for incident VTE was 2.0 (95% confidence interval [CI], 1.2-3.4) and after adjusting for age, BMI, and Charlson Comorbidity Index, the HR was 1.68 (95% CI, 0.98-2.89). The adjusted HR for ipsilateral deep vein thrombosis was evaluated in 3064 legs comparing legs with reduced to normal CPF and was 1.71 (95% CI, 1.03-2.84). Mortality was significantly higher in both the bilateral (P < .001) and unilateral (P < .001) rCPF groups compared with normal CPF. Our results demonstrate that CPF is a risk factor for VTE in an otherwise low-risk ambulatory population and might be a useful component in risk stratification models.
Reduced Calf Muscle Pump Function Is a Risk Factor for Venous Thromboembolism and Mortality
Background: Venous return from the lower extremities is pumped upwards to the right side of the heart in a process that is facilitated by one-way valves and the venous muscle pump, of which the calf muscle pump is a major contributor1-3. Venous plethysmography can quantitatively assess calf pump function (CPF). The association between the CPF and venous thromboembolism (VTE) has not been investigated. Methods: Venous plethysmography (VP) data (strain gauge or air plethysmography) from the Mayo Clinic Vascular Lab database (1998-2015) of CPF (bilaterally reduced, unilaterally reduced, and bilateral normal) were examined in Olmsted County Residents. The Rochester Epidemiology Project (REP) captures the population of Olmsted County and contains demographic information, medical diagnoses, hospital admissions, and surgical procedures as well as validated VTE events and death. Patients with signs of obstructed outflow in either extremity on the venous plethysmography (a possible sign of acute or chronic deep vein thrombosis) study were excluded. Patients with a history of VTE diagnosed before the physiologic study were also excluded. If more than one measurement of calf muscle pump function was performed, only the first measurement was used. The primary outcome was a composite of any VTE, including proximal and distal deep vein thrombosis (DVT) and pulmonary embolism (PE). Results: 1703 Olmsted County residents had venous plethysmography studies performed. MN research authorization was denied in 64 patients and 107 were excluded for any documented VTE preceding index VP study. 1532 patients with recorded CPF (28% air and 72% strain gauge plethysmography) were studied: 591 (38.5%) had normal CPF, 353 (23.0%) had unilateral reduced CPF (rCPF), and 588 (38.3%) had bilateral rCPF. The mean age was 64.4 (SD 18.4), 68.9% were female, and the mean BMI was 29.5 (SD 6.4). Any VTE occurred in 87 patients (5.7%) after a mean follow up of 10.9 years (range 0-22.0 years). Isolated lower extremity DVT (excluding concurrent PE) occurred in 49 patients and PE+/-DVT occurred in 38 patients. Death occurred in 352 patients (23%). Bilateral rCPF compared to bilateral normal CPF was associated with VTE (p=0.007), DVT only (p=0.02) and death (p<0.001) but not PE+/-DVT (p=0.13). Unilateral rCPF compared to bilateral normal CPF was not associated with VTE, but was associated with death (p<0.001). Kaplan-Meier curves for VTE and death are shown in Figure 1. The hazard ratio for bilateral rCPF compared to bilateral normal CPF for VTE was 2.0 (95% CI 1.2-3.4) and for DVT only was 2.2 (95% CI 1.1-4.2). A sensitivity analysis for the main outcome of VTE did not show significant interaction based on the type of plethysmography (strain vs. air), by age stratified at 65 years, sex, or BMI stratified at 30 (p>0.1 for each comparison). Conclusion: In this population-based study of Olmsted County residents with no prior VTE, rCPF function as measured by venous plethysmography is associated with increased risk for VTE, particularly lower extremity proximal DVT. More research is required to understand what additional measures of venous physiology influence these findings and whether CPF could be used in VTE risk stratification. Disclosures No relevant conflicts of interest to declare.
A Review of Pathophysiology, Clinical Features, and Management Options of COVID-19 Associated Coagulopathy
Abstract There is increasing evidence that novel coronavirus disease 2019 (COVID-19) leads to a significant coagulopathy, a phenomenon termed “COVID-19 associated coagulopathy.” COVID-19 has been associated with increased rates of both venous and arterial thromboembolic events, a source of significant morbidity and mortality in this disease. Further evidence suggests a link between the inflammatory response and coagulopathy associated with COVID-19. This presents a unique set of challenges for diagnosis, prevention, and treatment of thrombotic complications. In this review, we summarize and discuss the current literature on laboratory coagulation disruptions associated with COVID-19 and the clinical effects of thromboembolic events including pulmonary embolism, deep vein thrombosis, peripheral arterial thrombosis, and acute ischemic stroke in COVID-19. Endothelial injury and augmented innate immune response are implicated in the development of diffuse macro- and microvascular thrombosis in COVID-19. The pathophysiology of COVID-19 associated coagulopathy is an important determinant of appropriate treatment and monitoring of these complications. We highlight the importance of diagnosis and management of dysregulated coagulation in COVID-19 to improve outcomes in COVID-19 patients with thromboembolic complications.
Treatment of Cancer-Associated Venous Thromboembolism with Low-Molecular-Weight Heparin or Direct Oral Anticoagulants: Patient Selection, Controversies, and Caveats
The Oncologist | December 4, 2020 | Volume: 26 | Issue: 1 | Pages: e8-e16
Abstract The treatment of venous thromboembolism (VTE) in patients with cancer is challenging because these patients have increased risks of both recurrent VTE and major bleeding, along with patient-specific and cancer-related factors that influence the approach to treatment. Historically, anticoagulant therapy with low-molecular-weight heparin (LMWH), given for both initial and long-term treatment, has been the preferred approach recommended by practice guidelines. Most recently, the National Comprehensive Cancer Network (NCCN) guidelines indicate that the direct oral anticoagulants (DOACs) apixaban, edoxaban, or rivaroxaban are preferred for patients without gastric or gastroesophageal lesions. DOACs have been associated with an increased risk of major bleeding in patients with gastrointestinal and possibly genitourinary cancers, and DOACs should either not be used (especially in those with intact intraluminal tumors) or be used with caution in patients with these cancers. Fatal or life-threatening bleeding occurs with similar frequency with DOACs or LMWH, and most major bleeding with DOACs can be managed with transfusion and standard measures. The patient's willingness and ability to comply with LMWH injections, and their treatment preference, should also be considered. Patients with cancer who have VTE should be treated with anticoagulation for a minimum of 6 months. Anticoagulation should be continued indefinitely while cancer is active or under treatment or if there are persistent risk factors for recurrent VTE. This article summarizes the evidence from clinical trials of LMWH and DOACs that underpins the NCCN guideline recommendations, addresses several controversies and caveats regarding anticoagulant treatment, and offers evidence-based, practical suggestions on patient selection for treatment with DOACs. Implications for Practice Several randomized trials support the addition of direct oral anticoagulants (DOACs) to the therapeutic armamentarium for cancer-associated venous thromboembolism (VTE). These agents come with unique risks and patient- and cancer-specific variables that must be evaluated during the course of a patient's cancer care. This narrative review discusses findings from clinical trials of low-molecular-weight heparin and DOACs for the treatment of cancer-associated VTE, evidence that supports the recent National Comprehensive Cancer Network guideline recommendations. A personalized approach to treatment is proposed that addresses patient selection for treatment with DOACs, factors that influence efficacy and safety, controversies and caveats, and suggestions for their resolution in clinical practice.
Glucocorticoid therapy rather than the inflammatory state is associated with pulmonary embolism and deep vein thrombosis in cardiac sarcoid
European Heart Journal | November 26, 2020 | Volume: 41 | Issue: Supplement_2 | Pages: No page available
Abstract Background Sarcoidosis is an infiltrative inflammatory condition affecting multiple organs, with cardiac involvement designated as cardiac sarcoidosis (CS). It has been proposed that inflammatory conditions like sarcoid increase the risk of venous thromboembolism (VTE), defined as pulmonary embolism (PE) and deep vein thrombosis (DVT) due to the hypercoagulable environment created by inflammation. Purpose Although previous studies have demonstrated an association with sarcoidosis and VTE, these studies failed to account for steroid use (crucial for sarcoid treatment) as an important confounder. Also, no major studies have been done previously assessing the risk of VTE in CS specifically. The objective of this investigation is to determine the association between CS, steroid treatment for CS, and VTE. Methods Patients referred to our institution with concern for sarcoid/CS were retrospectively assessed. Specific variables of interest including general baseline characteristics and those specific to CS were analyzed for their association with VTE development. Results Using Heart Rhythm Society guidelines, 649 patients were split into three categories: 235 with no sarcoid (NS), 91 with extra-cardiac sarcoid (ECS) only, and 323 with CS. In univariate analysis, 39 (12%) CS patients developed a PE vs 9 (4%) NS patients (OR 3.44, p=0.0003) and 44 (14%) CS patients developed DVT vs 18 (8%) NS patients (OR 1.90, p=0.02). In multivariate regression analysis however, neither CS nor ECS was an independent risk factor for VTE (p>0.05) but steroid use was a strong predictor of VTE (HR 3.12, p=0.007 for PE, HR 6.17, p<0.0001 for DVT). Also, steroid dose was found to be an independent predictor for both PE (p=0.001) and DVT (p=0.007) in a Cox proportionate hazards model (significance appeared at >17.5 mg daily on a receiver operating characteristic curve). Conclusion Contrary to previous studies, the current study found that neither sarcoidosis nor CS is an independent risk factor for VTE. Rather, steroid therapy for CS treatment leads to an increased prevalence of VTE, specifically at a dose above 17.5 mg daily. More research is required to clarify this relationship and assess the importance of steroid-sparing immunosuppressive therapy and potentially VTE prophylaxis in CS management. Steroid use and time to PE/DVT Funding Acknowledgement Type of funding source: None
Association between Cancer and Anatomical Site of Venous Thromboembolic Disease
Background:There is limited published data on the association between malignancy and the location of venous thromboembolism (VTE) in the body. Aims:Assess the location of VTE in the body in patients with active cancer and compare these results in patients without malignancy. Methods:Consecutive patients enrolled in the Mayo Clinic VTE Registry between March 1, 2013 and November 30, 2019 for acute VTE were followed prospectively. Anatomical site of thrombosis and malignancy status were recorded. Patient outcomes were assessed in person, by mailed questionnaire, or by a scripted phone interview. Active cancer was defined as treatment for malignancy within the last six months or not yet in remission. Results:During the study period there were 2,798 patients with acute VTE (1256 with and 1542 without active cancer). Pulmonary emboli were more common in patients with active cancer compared to patients without cancer (49.5% vs. 39.7%, p<0.001). Upper extremity deep vein thrombosis (11.4 % vs. 7.7%, p<0.001), renal vein thrombi (1.4% vs. 0.2%, p<0.001) and splanchnic vein thrombi (9.3% vs. 6.0%, p=0.001) were all more common in patients with active cancer compared to patients without cancer. Conclusion:Compared to those without malignancy, patients with active cancer were more likely to have pulmonary emboli, upper extremity deep vein thrombosis, renal vein thrombi, and splanchnic vein thrombi. Disclosures No relevant conflicts of interest to declare.
Calf muscle pump function as a predictor of all-cause mortality
Vascular Medicine | September 25, 2020 | Volume: 25 | Issue: 6 | Pages: 519-526
Calf muscle pump (CMP) promotes venous return from the lower extremity and contributes to preload and cardiac output. Impaired CMP function may reflect a measure of frailty or cumulative disease burden or may impede cardiac function. The study objective was to test the hypothesis that impaired CMP negatively impacts survival. Consecutive adult patients who underwent venous strain gauge plethysmography at the Mayo Clinic Gonda Vascular Laboratory (January 1, 1998 – December 31, 2011) were assessed for overall survival. Patients with venous incompetence, venous obstruction or unilateral calf pump dysfunction were excluded. Risk of mortality was assessed with Cox proportional hazard ratios and after adjusting for Charlson Comorbidity Index variables. Over the study period, 2728 patients were included in the analysis. Compared to patients with normal CMP, those with impaired CMP were older ( p < 0.001), predominantly female ( p = 0.01) and had higher mean Charlson scores ( p < 0.001). Patients with impaired CMP had a higher mortality rate at 5 (8.9% vs 2.4%), 10 (17.5% vs 5.9%), and 15 years (22.8% vs 8.3%) compared to those with normal CMP ( p < 0.001 for each comparison). Of patients with heart failure, those with impaired CMP had worse survival at each 5-year increment compared to those with normal CMP ( p < 0.05 at each increment). In conclusion, impaired CMP appears to be an independent predictor of poor outcomes after adjusting for variables within the Charlson Comorbidity Index. The association between impaired CMP, heart failure, and mortality may represent a negative impact on circulatory function or a surrogate measure of frailty.
More Options for Cancer-associated Thrombosis: Apixaban Non-inferior to Dalteparin
The Hematologist | September 3, 2020 | Volume: 17 | Issue: 4 | Pages: No page available
Abstract Background The objective of this study was to characterize clinical features and outcomes among patients with calf deep vein thrombosis (DVT) limited to the muscular veins compared with axial veins. Methods Consecutive patients with ultrasound confirmed acute DVT involving the calf veins (January 1, 2016–August 1, 2018) were identified from the Gonda Vascular Center ultrasound database. Patients were divided into axial or muscular groups based on thrombus location. Demographics, management, and outcomes were compared. Results Over the study period, there were 647 patients with calf DVT equally distributed between axial (n = 321) and muscular (n = 326) locations. Within these groups, peroneal and soleal veins were most commonly involved. Nearly all cases were provoked (97%). Synchronous pulmonary embolism (PE) were more common for axial (30.8%) compared to muscular groups (20.2%; p = 0.001); nearly one-third had no pulmonary symptoms. Anticoagulation for a median of 3 months was initiated for 85.5% of both groups. Venous thromboembolism (VTE) recurrence was more common in the axial group (15.9% vs. 7.1%, p = 0.0015) including more frequent DVT propagation (9.4% vs. 3.1%; p = 0.0017) and PE (3.4% vs. 0.6%; p = 0.0168). Major bleeding, clinically relevant nonmajor bleeding, and mortality rates did not differ between groups. Withholding anticoagulation led to more frequent thrombus propagation in the axial group (3.4% vs. 0.9%; p = 0.029). Conclusion Several important features distinguish muscular from axial DVT. Axial DVT are more likely to have an associated PE and are more likely to experience recurrent VTE, particularly if anticoagulation is withheld.