Risk assessment tools for bleeding in patients with unprovoked venous thromboembolism: an analysis of the PLATO-VTE study.

BACKGROUND: Guidelines suggest indefinite anticoagulation after unprovoked venous thromboembolism (VTE) unless the bleeding risk is high, yet there is no consistent guidance on assessing bleeding risk. This study aimed to evaluate the performance of five bleeding risk tools (RIETE, VTE-BLEED, CHAP, VTE-PREDICT, and ABC-bleeding). METHODS: PLATO-VTE, a prospective cohort study, included patients aged ≥40 years with a first unprovoked VTE. Risk estimates were calculated at VTE diagnosis and after 3 months of treatment. Primary outcome was clinically relevant bleeding, as per ISTH criteria, during 24-month follow-up. Discrimination was assessed by the area under the receiver operating characteristic curve (AUROC). Patients were classified as having a 'high-risk' and 'non-high-risk' of bleeding according to predefined thresholds; bleeding risk in both groups was compared by hazard ratios. RESULTS: Of 514 patients, 38 (7.4%) had an on-treatment bleeding. AUROCs were 0.58 (95%CI, 0.48-0.68) for ABC-bleeding, 0.56 (95%CI, 0.46-0.66) for RIETE, 0.53 (95%CI, 0.43-0.64) for CHAP, 0.50 (95%CI, 0.41-0.59) for VTE-BLEED, and 0.50 (95%CI, 0.40-0.60) for VTE-PREDICT. The proportion of high-risk patients ranged from 1.4% with RIETE to 36.9% with VTE-BLEED. The bleeding incidence in the high-risk groups ranged from 0% with RIETE to 13.0% with ABC-bleeding, and in the non-high-risk groups from 7.7% with ABC-bleeding to 9.6% with RIETE. Hazard ratios ranged from 0.93 (95%CI, 0.46-1.9) for VTE-BLEED to 1.67 (95%CI, 0.86-3.2) for ABC-bleeding. Recalibration at 3-month follow-up did not alter the results. CONCLUSIONS: In this cohort, discrimination of currently available bleeding risk tools was poor. These data do not support their use in patients with unprovoked VTE.

[BLITZ-AF Cancer study: an international observational research project on patients with atrial fibrillation and cancer]. / Studio BLITZ-AF Cancer: un progetto di ricerca osservazionale internazionale sui pazienti con fibrillazione atriale e cancro.

BACKGROUND: Cancer is an important condition associated with the development of atrial fibrillation (AF). The objectives of the BLITZ-AF Cancer study were to collect real-life information on the clinical profile and use of antithrombotic drugs in patients with AF and cancer to improve clinical management, as well as the evaluation of the association between different antithrombotic treatments (or their absence) and the main clinical events. METHODS: European multinational, multicenter, prospective, non-interventional study conducted in patients with AF (electrocardiographically confirmed) and cancer occurring within 3 years. The CHA2DS2-VASc and the HAS-BLED scores were calculated in all enrolled patients. RESULTS: From June 2019 to July 2021, 1514 patients were enrolled, 36.5% women, from 112 cardiology departments in 6 European countries (Italy, Belgium, the Netherlands, Spain, Portugal and Ireland). Italy enrolled 971 patients in 77 centers. Average age of patients was 74 ± 9 years, of which 20.9% affected by heart failure, 18.1% by ischemic heart disease, 9.8% by peripheral arterial disease and 38.5% by valvular diseases; 41.5% of patients had a CHA2DS2-VASc score ≥4. The most represented cancer sites were lung (14.9%), colorectal tract (14.1%), prostate (8.8%), or non-Hodgkin's lymphoma (8.1%). Before enrollment, 16.6% of patients were not taking antithrombotic therapy, while 22.7% were on therapy with antiplatelet agents and/or low molecular weight heparin. After enrollment these percentages decreased to 7.7% and 16.6%, respectively and, at the same time, the percentage of patients on direct oral anticoagulant (DOAC) therapy increased from 48.4% to 68.4%, also to the detriment of those on vitamin K antagonist therapy. CONCLUSIONS: The BLITZ-AF Cancer study, which enrolled patients diagnosed with AF and cancer, highlights that the use of DOACs by cardiologists in this clinical context has increased, even though the guidelines on AF do not give accurate indications about oral anticoagulant therapy in patients with cancer.

Unmet needs and barriers in venous thromboembolism education and awareness among people living with cancer: a global survey.

BACKGROUND: Venous thromboembolism (VTE) is a major preventable cause of morbidity, disability, and mortality in subjects with cancer. A global appraisal of cancer-associated VTE education and awareness is not available. OBJECTIVES: To evaluate VTE-related education, awareness, and unmet needs from the perspective of people living with cancer using a quantitative and qualitative approach. METHODS: This cross-sectional study used data from an online-based survey covering multidimensional domains of cancer-associated VTE. Data are presented descriptively. Potential differences across participant subgroups were explored. RESULTS: Among 2262 patients with cancer from 42 countries worldwide, 55.3% received no VTE education throughout their cancer journey, and an additional 8.2% received education at the time of VTE diagnosis only, leading to 63.5% receiving no or inappropriately delayed education. When education was delivered, only 67.8% received instructions to seek medical attention in case of VTE suspicion, and 36.9% reported scarce understanding. One-third of participants (32.4%) felt psychologically distressed when becoming aware of the potential risks and implications connected with cancer-associated VTE. Most responders (78.8%) deemed VTE awareness highly relevant, but almost half expressed concerns about the quality of education received. While overall consistent, findings in selected survey domains appeared to numerically differ across age group, ethnicity, continent of residence, educational level, metastatic status, and VTE history. CONCLUSION: This study involving a large and diverse population of individuals living with cancer identifies important unmet needs in VTE-related education, awareness, and support across healthcare systems globally. These findings unveil multilevel opportunities to expedite patient-centered care in cancer-associated VTE prevention and management.

Inflammasome Signaling, Thromboinflammation, and Venous Thromboembolism.

Venous thromboembolism (VTE) remains a major health burden despite anticoagulation advances, suggesting incomplete management of pathogenic mechanisms. The NLRP3 (NACHT-, LRR- and pyrin domain-containing protein 3) inflammasome, interleukin (IL)-1, and pyroptosis are emerging contributors to the inflammatory pathogenesis of VTE. Inflammasome pathway activation occurs in patients with VTE. In preclinical models, inflammasome signaling blockade reduces venous thrombogenesis and vascular injury, suggesting that this therapeutic approach may potentially maximize anticoagulation benefits, protecting from VTE occurrence, recurrence, and ensuing post-thrombotic syndrome. The nonselective NLRP3 inhibitor colchicine and the anti-IL-1ß agent canakinumab reduce atherothrombosis without increasing bleeding. Rosuvastatin reduces primary venous thrombotic events at least in part through lipid-lowering independent mechanisms, paving the way to targeted anti-inflammatory strategies in VTE. This review outlines recent preclinical and clinical evidence supporting a role for inflammasome pathway activation in venous thrombosis, and discusses the, yet unexplored, therapeutic potential of modulating inflammasome signaling to prevent and manage VTE.

Common Practice in the Treatment of Superficial Vein Thrombosis Involving the Sapheno-Femoral Junction: Results from a National Survey of the Italian Society of Angiology and Vascular Medicine (SIAPAV).

Background and Objectives: Prophylactic doses of low-molecular-weight heparins or fondaparinux showed their efficacy and safety for treatment of all superficial vein thrombosis (SVT) of the lower limbs, yet not for those extended to the last 3 cm of the great saphenous vein, close to the sapheno-femoral junction, or considered as a deep-vein thrombosis. Some experts suggest that these patients should be managed with full anticoagulant doses but evidence to support this recommendation is lacking, suggesting the need for a properly designed trial. Materials and Methods: Before starting a new trial, the Italian Society of Angiology and Vascular Medicine (SIAPAV) decided to verify the common therapeutic approaches for patients with an SVT in Italian vascular centers based on a hypothetical significant variation in each daily clinical practice. A standardized questionnaire of 10 questions was administered to all SIAPAV affiliates by means of the official Society website. Results: From 1 December 2022 to 20 January 2023 a total of 191 members (31.8%) answered the questionnaire, showing a detailed and a substantial heterogeneity in the therapeutic approach to SVT patients among experienced vascular physicians and angiologists. Detailed results are reported in the relative section. Conclusions: The therapeutic approach of SVT extended to the iuxta-femoral segment of the great saphenous vein is still a matter of debate, and data to support therapeutic strategies are lacking. The wide heterogeneity in the management of SVT patients, including those with more extended thrombosis, confirmed that a randomized controlled clinical trial investigating the efficacy and the safety of a tailored therapeutic regimen in this particular subgroup of patients is strongly warranted.

NLRP3 inflammasome and interleukin-1 contributions to COVID-19-associated coagulopathy and immunothrombosis.

Immunothrombosis-immune-mediated activation of coagulation-is protective against pathogens, but excessive immunothrombosis can result in pathological thrombosis and multiorgan damage, as in severe coronavirus disease 2019 (COVID-19). The NACHT-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasome produces major proinflammatory cytokines of the interleukin (IL)-1 family, IL-1ß and IL-18, and induces pyroptotic cell death. Activation of the NLRP3 inflammasome pathway also promotes immunothrombotic programs including release of neutrophil extracellular traps and tissue factor by leukocytes, and prothrombotic responses by platelets and the vascular endothelium. NLRP3 inflammasome activation occurs in patients with COVID-19 pneumonia. In preclinical models, NLRP3 inflammasome pathway blockade restrains COVID-19-like hyperinflammation and pathology. Anakinra, recombinant human IL-1 receptor antagonist, showed safety and efficacy and is approved for the treatment of hypoxaemic COVID-19 patients with early signs of hyperinflammation. The non-selective NLRP3 inhibitor colchicine reduced hospitalization and death in a subgroup of COVID-19 outpatients but is not approved for the treatment of COVID-19. Additional COVID-19 trials testing NLRP3 inflammasome pathway blockers are inconclusive or ongoing. We herein outline the contribution of immunothrombosis to COVID-19-associated coagulopathy, and review preclinical and clinical evidence suggesting an engagement of the NLRP3 inflammasome pathway in the immunothrombotic pathogenesis of COVID-19. We also summarize current efforts to target the NLRP3 inflammasome pathway in COVID-19, and discuss challenges, unmet gaps, and the therapeutic potential that inflammasome-targeted strategies may provide for inflammation-driven thrombotic disorders including COVID-19.

Prognostic role of different findings at echocardiography in acute pulmonary embolism: a critical review and meta-analysis.

Background: Right ventricle dysfunction (RVD) at echocardiography predicts mortality in patients with acute pulmonary embolism (PE), but heterogeneous definitions of RVD have been used. We performed a meta-analysis to assess the role of different definitions of RVD and of individual parameters of RVD as predictors of death. Methods: A systematic search for studies including patients with confirmed PE reporting on right ventricle (RV) assessment at echocardiography and death in the acute phase was performed. The primary study outcome was death in-hospital or at 30 days. Results: RVD at echocardiography, regardless of its definition, was associated with increased risk of death (risk ratio 1.49, 95% CI 1.24-1.79, I2=64%) and PE-related death (risk ratio 3.77, 95% CI 1.61-8.80, I2=0%) in all-comers with PE, and with death in haemodynamically stable patients (risk ratio 1.52, 95% CI 1.15-2.00, I2=73%). The association with death was confirmed for RVD defined as the presence of at least one criterion or at least two criteria for RV overload. In all-comers with PE, increased RV/left ventricle (LV) ratio (risk ratio 1.61, 95% CI 1.90-2.39) and abnormal tricuspid annular plane systolic excursion (TAPSE) (risk ratio 2.29 CI 1.45-3.59) but not increased RV diameter were associated with death; in haemodynamically stable patients, neither RV/LV ratio (risk ratio 1.11, 95% CI 0.91-1.35) nor TAPSE (risk ratio 2.29, 95% CI 0.97-5.44) were significantly associated with death. Conclusion: Echocardiography showing RVD is a useful tool for risk stratification in all-comers with acute PE and in haemodynamically stable patients. The prognostic value of individual parameters of RVD in haemodynamically stable patients remains controversial.

Apixaban thromboprophylaxis in ambulatory patients with cancer and obesity: Insights from the AVERT trial.

BACKGROUND: The use of direct oral anticoagulants (DOACs) in obese patients is uncertain. It is unclear if body mass index (BMI) affects the safety and efficacy of DOACs for the primary prevention of venous thromboembolism (VTE) in high-risk ambulatory patients with cancer. We sought to determine the outcomes associated with the use of apixaban for the primary prevention of cancer-associated VTE according to BMI. METHODS: The randomized, double-blinded, placebo-controlled AVERT trial evaluated apixaban thromboprophylaxis in intermediate-to-high risk ambulatory cancer patients receiving chemotherapy. For this post-hoc analysis, the primary efficacy and safety outcomes were objectively confirmed VTE and clinically relevant bleeding (major and clinically relevant non-major bleeding), respectively. Obesity was defined as BMI ≥30 kg/m2. RESULTS: Among 574 patients randomized, 217 (37.8 %) patients had BMI ≥30 kg/m2. Obese patients were overall younger, more likely to be female, had higher creatinine clearance and hemoglobin, lower platelet count, and better ECOG performance status. Compared to placebo, apixaban thromboprophylaxis was associated with reduced VTE in both obese (hazard ratio [HR] 0.26; 95 % confidence interval [CI], 0.14-0.46; p < 0.0001) and non-obese (HR 0.54; 95%CI, 0.29-1.00; p = 0.049) patients. The HR for clinically relevant bleeding (apixaban vs. placebo) was numerically higher in obese (2.09; 95%CI, 0.96-4.51; p = 0.062) than non-obese subjects (1.23; 95%CI, 0.71-2.13; p = 0.46), but overall in line with the risks observed in the general trial population. CONCLUSIONS: In the AVERT trial enrolling ambulatory cancer patients receiving chemotherapy, we found no substantial differences in the efficacy or safety of apixaban thromboprophylaxis across obese and non-obese subjects.

Clinical course and treatment of incidentally detected splanchnic vein thrombosis: an individual patient data meta-analysis.

BACKGROUND: The clinical relevance and management of incidental splanchnic vein thrombosis (SVT) remain poorly defined. OBJECTIVES: The objectives of this study were to evaluate the clinical course of incidental SVT in comparison with symptomatic SVT and assess the safety and effectiveness of anticoagulant treatment in incidental SVT. METHODS: Individual patient data meta-analysis of randomized controlled trials or prospective studies published up to June 2021. Efficacy outcomes were recurrent venous thromboembolism (VTE) and all-cause mortality. The safety outcome was major bleeding. Incidence rate ratios and 95% CIs for incidental vs symptomatic SVT were estimated before and after propensity-score matching. Multivariable Cox models were used considering anticoagulant treatment as a time-varying covariate. RESULTS: In total, 493 patients with incidental SVT and 493 propensity-matched patients with symptomatic SVT were analyzed. Patients with incidental SVT were less likely to receive anticoagulant treatment (72.4% vs 83.6%). Incidence rate ratios (95% CI) for major bleeding, recurrent VTE, and all-cause mortality in patients with incidental SVT compared with symptomatic SVT were 1.3 (0.8, 2.2), 2.0 (1.2, 3.3), and 0.5 (0.4, 0.7), respectively. In patients with incidental SVT, anticoagulant therapy was associated with a lower risk of major bleeding (hazard ratio [HR] 0.41; 95% CI, 0.21 to 0.71), recurrent VTE (HR 0.33; 95% CI, 0.18 to 0.61), and all-cause mortality (HR 0.23; 95% CI, 0.15 to 0.35). CONCLUSION: Patients with incidental SVT appeared to have a similar risk of major bleeding, a higher risk of recurrent thrombosis, but lower all-cause mortality than patients with symptomatic SVT. Anticoagulant therapy seemed safe and effective in patients with incidental SVT.

Age- versus clinical pretest probability-adjusted D-dimer to rule out lower-extremity deep vein thrombosis in ambulatory patients with active cancer.

BACKGROUND: In patients with suspected deep vein thrombosis (DVT), D-dimer thresholds adjusted to age or clinical pretest probability (CPTP) increase the proportion of patients in whom DVT can be safely excluded compared to a standard approach using a fixed D-dimer threshold. Performance of these diagnostic strategies among cancer patients is uncertain. AIM: To compare the performance of age- and CPTP-adjusted D-dimer approaches among cancer outpatients with clinically suspected DVT, and derive a cancer-specific CPTP rule. PATIENTS AND METHODS: Consecutive ambulatory patients with active cancer and clinically suspected DVT of the lower extremity underwent CPTP assessment using the Wells rule, D-dimer testing, and whole-leg compression ultrasonography. Patients with normal ultrasonography were followed-up for 3 months for the occurrence of symptomatic venous thromboembolism. RESULTS: Upon referral, DVT was diagnosed in 48 of 239 (20.1 %) patients. The age-adjusted approach showed higher specificity and efficiency than the standard approach. Compared to the standard and age-adjusted strategies, the CPTP-adjusted approach had 35 % and 21 % higher specificity, and 34 % and 21 % higher efficiency, respectively. Failure rate, sensitivity, and predictive values were similar across strategies. A simplified CPTP score derived from the Wells rule reduced unnecessary imaging with similar accuracy and efficiency, but higher failure rate. CONCLUSIONS: In this prospective cohort of ambulatory cancer patients with clinically suspected DVT, the CPTP-adjusted D-dimer approach held the highest specificity and efficiency, potentially safely reducing unnecessary ultrasonography examinations compared to other approaches. Additional studies are warranted to evaluate the use of a simplified clinical prediction rule in this setting.

Platelet RNA sequencing for cancer screening in patients with unprovoked venous thromboembolism: a prospective cohort study.

BACKGROUND: Platelet RNA sequencing has been shown to accurately detect cancer in previous studies. OBJECTIVES: To compare the diagnostic accuracy of platelet RNA sequencing with standard-of-care limited cancer screening in patients with unprovoked venous thromboembolism (VTE). METHODS: Patients aged ≥40 years with unprovoked VTE were recruited at 13 centers and followed for 12 months for cancer. Participants underwent standard-of-care limited cancer screening, and platelet RNA sequencing analysis was performed centrally at study end for cases and selected controls. Sensitivity and specificity were calculated, using the predefined primary positivity threshold of 0.54 for platelet RNA sequencing aiming at 86% test sensitivity, and an additional predefined threshold of 0.89 aiming at 99% test specificity. RESULTS: A total of 476 participants were enrolled, of whom 25 (5.3%) were diagnosed with cancer during 12-month follow-up. For each cancer patient, 3 cancer-free patients were randomly selected for the analysis. The sensitivity of limited screening was 72% (95% CI, 52-86) at a specificity of 91% (95% CI, 82-95). The area under the receiver operator characteristic for platelet RNA sequencing was 0.54 (95% CI, 0.41-0.66). At the primary positivity threshold, all patients had a positive test, for a sensitivity estimated at 100% (95% CI, 87-99) and a specificity of 8% (95% CI, 3.7-16.4). At the secondary threshold, sensitivity was 68% (95% CI, 48-83; p value compared with limited screening 0.71) at a specificity of 36% (95% CI, 26-47). CONCLUSION: Platelet RNA sequencing had poor diagnostic accuracy for detecting occult cancer in patients with unprovoked VTE with the current algorithm.

Antithrombotic treatment for retinal vein occlusion: a systematic review and meta-analysis.

BACKGROUND: Retinal vein occlusion (RVO) represents a common thrombotic disorder. OBJECTIVES: In this meta-analysis, we evaluated the efficacy and safety of anticoagulant and antiplatelet therapy in RVO. METHODS: MEDLINE and EMBASE were searched up to December 2021 for observational studies and randomized controlled trials including patients with RVO. Efficacy outcomes were best-corrected visual acuity improvement, recurrent RVO, fluorescein angiography improvement, cardiovascular events, and safety outcomes were major bleeding and intraocular bleeding. RESULTS: A total of 1422 patients (15 studies) were included. Antiplatelet therapy was administered to 477 patients (13 studies), anticoagulant therapy to 312 patients (12 studies), and 609 (7 studies) patients received no antithrombotic treatment. The treatment duration ranged between 0.5 and 3 months. The median follow-up duration was 12 months. Best-corrected visual acuity improvement was reported in 58% of the patients (95% confidence interval [CI], 45%-69%) overall, 64% (95% CI, 58%-71%) in those on anticoagulant therapy, and 33% (95% CI, 21%-47%) in those on antiplatelet therapy. The rates of recurrent RVO was 11% (95% CI, 7%-17%), 7% (95% CI, 2%-19%), and 15% (95% CI, 8%-28%), respectively. The rate of recurrent RVO in untreated patients was 9% (95% CI, 6%-14%). The rate of major bleeding was 5% (95% CI, 3%-9%) overall, 4% (95% CI, 2%-9%) in those on anticoagulant therapy, and 7% (95% CI, 2%-23%) in those on antiplatelet therapy. CONCLUSION: Anticoagulant therapy was associated with higher visual acuity improvement and fewer recurrent RVO events than antiplatelet therapy, at the cost of an acceptable proportion of bleeding complications.

Anamnestic frailty phenotype and adverse outcomes in patients treated with direct oral anticoagulants: Validation and comparative performance with frailty phenotype.

AIMS: The anamnestic frailty phenotype (AFP) is a quick, instrument-free tool derived from frailty phenotype (FP). We prospectively evaluated the discriminative capacity and prognostic value of AFP in ambulatory patients receiving DOACs for atrial fibrillation (AF) or venous thromboembolism (VTE), and compared AFP performance with that of FP. METHODS AND RESULTS: Sensitivity, specificity, positive and negative predictive value (PPV, NPV) with corresponding 95% confidence intervals (95%CI), were estimated for bleeding, thromboembolism, and all-cause mortality. Risk ratios (RRs) were calculated in frail versus non-frail patients. Of 236 patients (median age 78 years), 98 (42%) and 89 (38%) were classified as frail according to FP and AFP, respectively (Kappa= 0.76). Frailty, as assessed by AFP, was associated with higher risk of bleeding (RR 2.3; 95%CI, 1.2 to 4.6), and mortality (RR 4.4; 95%CI, 1.3 to 19.7). Similarly, to FP, AFP exhibited modest sensitivity and specificity, but high NPV that was 91% (95%CI, 85 to 95) for bleeding, 98% (95%CI, 94 to 100) for thromboembolism, and 98% (95%CI, 94 to 100) for mortality. CONCLUSION: Among patients receiving DOACs for AF or VTE, AFP was associated with an increased risk of adverse outcomes. AFP exhibited modest sensitivity and specificity, but excellent NPV. If confirmed, these findings suggest that AFP may represent a rapid, easy-to-use and unexpensive tool that may potentially help identify patients at lower risk for adverse outcomes and tailor anticoagulation management.

Awareness of venous thromboembolism among patients with cancer: Preliminary findings from a global initiative for World Thrombosis Day.

BACKGROUND: Cancer-associated venous thromboembolism (CAT) has detrimental impact on patients' clinical outcomes and quality of life. Data on CAT education, communication, and awareness among the general cancer population are scanty. METHODS: We present the preliminary results of an ongoing patient-centered survey including 27 items covering major spheres of CAT. The survey, available in 14 languages, was promoted and disseminated online through social networks, email newsletters, websites, and media. RESULTS: As of September 20, 2022, 749 participants from 27 countries completed the survey. Overall, 61.8% (n = 460) of responders were not aware of their risk of CAT. Among those who received information on CAT, 26.2% (n = 56) were informed only at the time of CAT diagnosis. Over two thirds (69.1%, n = 501) of participants received no education on signs and symptoms of venous thromboembolism (VTE); among those who were educated about the possible clinical manifestations, 58.9% (n = 119) were given instructions to seek consultation in case of VTE suspicion. Two hundred twenty-four respondents (30.9%) had a chance to discuss the potential use of primary thromboprophylaxis with health-care providers. Just over half (58.7%, n = 309) were unaware of the risks of bleeding associated with anticoagulation, despite being involved in anticoagulant-related discussions or exposed to anticoagulants. Most responders (85%, n = 612) valued receiving CAT education as highly relevant; however, 51.7% (n = 375) expressed concerns about insufficient time spent and clarity of education received. CONCLUSIONS: This ongoing survey involving cancer patients with diverse ethnic, cultural, and geographical backgrounds highlights important patient knowledge gaps. These findings warrant urgent interventions to improve education and awareness, and reduce CAT burden.

Frailty phenotype as a predictor of bleeding and mortality in ambulatory patients receiving direct oral anticoagulants.

BACKGROUND: Limited prospective data exist about the clinical relevance of frailty in patients with atrial fibrillation (AF) or venous thromboembolism (VTE) receiving direct oral anticoagulants (DOACs). The aim of this study was to evaluate whether frailty phenotype identifies DOAC-treated patients at higher risk of adverse clinical outcomes. METHODS: Consecutive, adult outpatients treated with DOACs for AF or VTE were prospectively enrolled. Patients were classified as frail, pre-frail, or non-frail according to frailty phenotype. Study outcomes were clinically relevant bleeding, including major and clinically relevant non-major bleeding, arterial and venous thromboembolism, and all-cause mortality. RESULTS: 236 patients (median age 78 years, 44% females) were included, of whom 156 (66%) had AF and 80 (34%) VTE. Ninety-eight (41%) patients were frail, 115 (49%) pre-frail, and 23 (10%) non-frail. Inappropriately high or low dose DOAC was used in 33% of frail and in 20% of non-frail or pre-frail patients. Over a median follow-up of 304 days, the incidence of clinically relevant bleeding, thromboembolism, and mortality were 20%, 4%, 9% in frail, and 10%, 3%, and 2% in pre-frail, respectively, while no study outcome occurred among non-frail patients. Risk ratios (95% confidence intervals) for these outcomes in frail versus pre-frail and non-frail patients were respectively 2.5 (1.8, 3.7), 1.9 (0.9, 4.0), and 6.3 (2.9, 13.6). CONCLUSION: In a prospective cohort of ambulatory patients receiving DOAC treatment for AF or VTE, frailty phenotype identified patients at higher risk of bleeding and all-cause mortality. Frailty assessment could be valuable to guide targeted interventions potentially improving patient prognosis.

High-dose versus low-dose venous thromboprophylaxis in hospitalized patients with COVID-19: a systematic review and meta-analysis.

BACKGROUND: Hospitalized COVID-19 patients are at high risk of venous thromboembolism (VTE). Standard doses of anticoagulant prophylaxis may not be sufficiently effective for the prevention of VTE. The objective of this systematic-review and meta-analysis was to compare the efficacy and safety of high-dose versus low-dose thromboprophylaxis in hospitalized patients with COVID-19. MATERIAL AND METHODS: MEDLINE and EMBASE were searched up to October 2021 for randomized clinical trials (RCTs) comparing high-dose with low-dose thromboprophylaxis in hospitalized adult patients with COVID-19. The primary efficacy outcome was the occurrence of VTE and the primary safety outcome was major bleeding. RESULTS: A total of 5470 patients from 9 RCTs were included. Four trials included critically ill patients, four non-critically ill patients, and one included both. VTE occurred in 2.9% of patients on high-dose and in 5.7% of patients on low-dose thromboprophylaxis (relative risk [RR] 0.53; 95% confidence intervals [CIs], 0.41-0.69; I2 = 0%; number needed to treat for an additional beneficial outcome, 22). Major bleeding occurred in 2.5% and 1.4% of patients, respectively (RR 1.78; 95% CI, 1.20-2.66; I2 = 0%; number needed to treat for an additional harmful outcome, 100). All-cause mortality did not differ between groups (RR 0.97; 95% CI, 0.75-1.26; I2 = 47%). The risk of VTE was significantly reduced by high-dose thromboprophylaxis in non-critically ill (RR 0.54; 95% CI, 0.35-0.86; I2 = 0%), but not in critically ill patients (RR 0.69; 95% CI, 0.39-1.21; I2 = 36%). DISCUSSION: In hospitalized patients with COVID-19, high-dose thromboprophylaxis is more effective than low-dose for the prevention of VTE but increases the risk of major bleeding.

Unanswered questions in cancer-associated thrombosis.

Cancer-associated venous thromboembolism (VTE) is a leading cause of morbidity and mortality in patients with cancer. Treatment of cancer-associated VTE comes with a heightened risk of anticoagulant-related bleeding that differs by choice of anticoagulant as well as by patient- and disease-specific risk factors. Available data from randomized controlled trials and observational studies in cancer-associated VTE suggest that direct oral anticoagulants are effective, continuing anticoagulation beyond six months is indicated in those with active cancer and that patients who develop 'breakthrough' thrombotic events can be effectively treated. We review the evidence that addresses these key clinical questions and offer pragmatic approaches in individualizing care. While significant investigative efforts over the past decade have made impactful advances, future research is needed to better define the factors that contribute to anticoagulant-related bleeding and VTE recurrence, in order to aid clinical decision-making that improves the care of patients with cancer-associated VTE.