Bleeding risk represents a major concern in anticoagulated patients with atrial fibrillation (AF). Several bleeding prediction scores have been described: HAS-BLED, ATRIA, HEMORR2HAGES and ORBIT. Of these, only HAS-BLED considers quality of anticoagulation control amongst vitamin K antagonist (VKA) users. We hypothesised that predictive value of bleeding risk scores other than HAS-BLED could be improved incorporating time in therapeutic range (TTR) in warfarin-treated patients. Of the 127 adjudicated major bleeding events, 21.3% of events occurred in 'low-risk' HAS-BLED category (1.8 per 100 patient-years), compared to higher proportions (≥50% of events; ~2.5 per 100 patient-years) in 'low-risk' categories for other scores. Only the 'low-risk' HAS-BLED category was associated with the absence of investigator-defined major bleeding events (OR: 1.46;95% CI: 1.00-2.15). 'High' or 'medium/high' risk categories for the HAS-BLED (p = 0.023) or ORBIT (p = 0.022) scores, respectively, conferred significant risk for adjudicated major bleeding events. On Cox regression analysis, adjudicated major bleeding was associated only with HAS-BLED (HR: 1.62;95% CI: 1.06-2.48) and ORBIT (HR: 1.83;95% CI: 1.08-3.09) 'high-risk' categories. Adding 'labile INR' (TTR < 65%) to ORBIT, ATRIA and HEMORR2HAGES significantly improved their reclassification and discriminatory performances. In conclusion, HAS-BLED categorised adjudicated major bleeding events in low-risk and high-risk patients appropriately, whilst ORBIT and ATRIA categorised most major bleeds into their 'low-risk' patient categories. Adding TTR to ORBIT, ATRIA and HEMORR2HAGES led to improved predictive performance for major bleeding.

Background Deep vein thrombosis (DVT) is the primary cause of pulmonary embolism and the third most life-threatening cardiovascular disease in North America. Post-DVT anticoagulants, such as warfarin, heparin, and direct oral anticoagulants, reduce the incidence of subsequent venous thrombi. However, all currently used anticoagulants affect bleeding time at various degrees, and there is therefore a need for improved therapeutic regimens in DVT. It has recently been shown that mast cells play a crucial role in a DVT murine model. The underlying mechanism involved in the prothrombotic properties of mast cells, however, has yet to be identified. Methods and Results C57BL/6 mice and mouse mast cell protease-4 (mMCP-4) genetically depleted mice (mMCP-4 knockout) were used in 2 mouse models of DVT, partial ligation (stenosis) and ferric chloride-endothelial injury model of the inferior vena cava. Thrombus formation and impact of genetically repressed or pharmacologically (specific inhibitor TY-51469) inhibited mMCP-4 were evaluated by morphometric measurements of thrombi immunochemistry (mouse and human DVT), color Doppler ultrasound, bleeding times, and enzymatic activity assays ex vivo. Recombinant chymases, mMCP-4 (mouse) and CMA-1 (human), were used to characterize the interaction with murine and human plasmin, respectively, by mass spectrometry and enzymatic activity assays. Inhibiting mast cell-generated mMCP-4, genetically or pharmacologically, resolves and prevents venous thrombus formation in both DVT models. Inferior vena cava blood flow obstruction was observed in the stenosis model after 6 hours of ligation, in control- but not in TY-51469-treated mice. In addition, chymase inhibition had no impact on bleeding times of healthy or DVT mice. Furthermore, endogenous chymase limits plasmin activity in thrombi ex vivo. Recombinant mouse or human chymase degrades/inactivates purified plasmin in vitro. Finally, mast cell-containing immunoreactive chymase was identified in human DVT. Conclusions This study identified a major role for mMCP-4, a granule-localized protease of chymase type, in DVT formation. These findings support a novel pharmacological strategy to resolve or prevent DVT without affecting the coagulation cascade through the inhibition of chymase activity.

Fibrin formation and histidine-rich glycoprotein (HRG) are involved in primary hemostasis and wound healing. Little is known regarding the relationship of clot characteristics, bleeding time, and wound healing.

It is important to identify risk factors for post-thyroidectomy bleeding requiring airway intervention or reoperation. Therefore, we aimed to compare the characteristics of patients with postoperative bleeding after thyroid surgery according to the period until reoperation. We conducted a retrospective study analyzing data between April 2009 and July 2022 and included 126 patients who had postoperative bleeding. The patients were grouped according to the period between thyroidectomy and reoperation due to bleeding (0 day, 1-7 days, > 7 days). We performed among-group comparisons of patient characteristics and surgical aspects, including the extent of surgery. The ratios of male-female and lateral neck dissection were higher in the post-operative bleeding group than in the group without bleeding. In the analysis of patients with postoperative bleeding, grouped according to period between thyroidectomy and reoperation, there was a significant among-group difference in the male-female ratio. The male sex was positively correlated with the reoperation period. Further, the reoperation period was also positively correlated with total thyroidectomy and lateral neck dissection and the operation time showed a significant among-group difference. Our results indicate that the male sex and lateral neck dissection are risk factors for postoperative bleeding after thyroidectomy. Furthermore, male sex, total thyroidectomy, and lateral neck dissection are risk factors for delayed bleeding. Therefore, clinicians should consider these factors for interventions against immediate or delayed bleeding after thyroidectomy.

Traumatic brain injury (TBI) and alcohol use disorder (AUD) can occur concomitantly and be associated with coagulopathy that influences TBI outcome. The use of bleeding time tests in TBI management is controversial. We hypothesized that in TBI patients with AUD, a prolonged bleeding time is associated with more severe injury and poor outcome.

Bleeding time test is used to assess the function of platelets in human body. The aim of this project was thus to estimate the sample size required to determine the normal range of bleeding time (BT) in Borujerd (a city in Iran). A pilot study was designed to determine the range of normal BT in a small group of normal people. The total sample size for the next study was then calculated according to the results.

No abstract available

Bleeding risk with vitamin K antagonists (VKAs) is closely related to the quality of anticoagulation in atrial fibrillation (AF) patients, reflected by time in therapeutic range (TTR). Here we compared the discrimination performance of different bleeding risk scores and investigated if adding TTR would improve their predictive value and clinical usefulness. We included 1361 AF patients stables on VKA for at least 6 months. Bleeding risk was assessed by the HAS-BLED, ATRIA, ORBIT and HEMORR2HAGES scores. Major bleeding events were recorded after a median of 6.5 years follow-up. In this period 250 patients suffered major bleeds. Comparison of receiver operating characteristic (ROC) curves demonstrated that HAS-BLED had the best discrimination performance, but adding the 'labile INR' criteria (i.e. TTR <65%) to ATRIA, ORBIT and HEMORR2HAGES increased their ability of discrimination and predictive value, with significant improvements in reclassification and discriminatory performance. Decision curve analyses (DCA) showed improvements of the clinical usefulness and a net benefit of the modified risk scores. In summary, in AF patients taking VKAs, the HAS-BLED score had the best predictive ability. Adding 'labile INR' to ATRIA, ORBIT and HEMORR2HAGES improved their predictive value for major bleeding leading to improved clinical usefulness compared to the original scores.

Publications on the exposure-effect relationships of factor concentrates for hemophilia treatment are limited, whereas such analyses give insight on treatment efficacy. Our objective was to examine the relationship between the dose, factor VIII (FVIII) levels and bleeding for rFVIII-SingleChain (lonoctocog alfa, Afstyla). Data from persons with severe hemophilia A on rFVIII-SingleChain prophylaxis from three clinical trials were combined. The published rFVIII-SingleChain population pharmacokinetic (PK) model was evaluated and expanded. The probability of bleeding was described with a parametric repeated time-to-event (RTTE) model. Data included 2080 bleeds, 2545 chromogenic stage assay, and 3052 one-stage assay FVIII levels from 241 persons (median age 19 years) followed for median 1090 days. The majority of the bleeds occurred in joints (65%) and the main bleeding reason was trauma (44%). The probability of bleeding decreased during follow-up and a FVIII level of 8.9 IU/dL (95% confidence interval: 6.9-10.9) decreased the bleeding hazard by 50% compared to a situation without FVIII in plasma. Variability in bleeding hazard between persons with similar FVIII levels was large, and the pre-study annual bleeding rate explained part of this variability. When a FVIII trough level of 1 or 3 IU/dL is targeted during prophylaxis, simulations predicted two (90% prediction interval [PI]: 0-17) or one (90% PI: 0-11) bleeds per year, respectively. In conclusion, the developed PK-RTTE model adequately described the relationship between dose, FVIII levels and bleeds for rFVIII-SingleChain. The obtained estimates were in agreement with those published for the FVIII concentrates BAY 81-8973 (octocog alfa) and BAY 94-9027 (damoctocog alfa pegol), indicating similar efficacy to reduce bleeding.

Only few studies have assessed the preventive effect of the STOPP/START criteria on adverse events. We aim to quantify 1) the association between nonadherence to STOPP/START criteria and gastrointestinal bleedings, and 2) the association between exposure to the potentially harmful START-medications and gastrointestinal bleedings.

Background Elderly patients have high ischemic and bleeding rates after acute coronary syndrome; however, the occurrence of these complications over time has never been studied. This study sought to characterize average daily ischemic rates ( ADIRs ) and average daily bleeding rates ( ADBRs ) over 1 year in patients aged >74 years with acute coronary syndrome undergoing percutaneous coronary intervention who were randomized in the Elderly ACS 2 trial, comparing low-dose prasugrel (5 mg daily) with clopidogrel (75 mg daily). Methods and Results ADIRs and ADBRs were calculated as the total number of events, including recurrent events, divided by the number of patient-days of follow-up and assessed within different clinical phases: acute (0-3 days), subacute (4-30 days), and late (31-365 days). Generalized estimating equations were used to test the least squares mean differences for the pairwise comparisons of ADIRs and ADBRs and the pairwise comparison of clopidogrel versus prasugrel effects. Globally, ADIRs were 2.6 times (95% CI, 2.4-2.9) higher than ADBRs . ADIRs were significantly higher in the clopidogrel arm than in the low-dose prasugrel arm in the subacute phase ( Padj<0.001) without a difference in ADBRs ( Padj=0.35). In the late phase, ADIRs remained significantly higher with clopidogrel ( Padj<0.001), whereas ADBRs were significantly higher with low-dose prasugrel ( Padj<0.001). Conclusions Ischemic burden was greater than bleeding burden in all clinical phases of 1-year follow-up of elderly patients with acute coronary syndrome treated with percutaneous coronary intervention. Low-dose prasugrel reduced ischemic events in the subacute and chronic phases compared with clopidogrel, whereas bleeding burden was lower with clopidogrel in the late phase. Clinical Trial Registration URL : http://www.clinicaltrials.gov . Unique identifier: NCT 01777503.

Platelets have an important role in thrombosis and haemostasis. Hyperactivity of the platelets has been associated with thromboembolic diseases and represents the main cause of complications of cardiovascular diseases. Crude aqueous extract (CAE) of Juglans regia root bark was evaluated for bleeding time, antiaggregant activity by using agonists, thrombin, ADP, collagen, or arachidonic acid (in vitro and ex vivo), and anticoagulant activity by measuring the clotting parameters: activated partial thromboplastin time, prothrombin time, thrombin time, and fibrinogen dosage (in vitro and ex vivo). The result of this study reported that the strongest antiaggregant effect of CAE in vitro was observed on the ADP-induced aggregation with inhibitions up to 90 %, while, in ex vivo experiments, the inhibition (more than 80 %) was observed with all agonists. Anticoagulant effect of CAE significantly prolonged the TT and decreased the fibrinogen level in vitro and ex vivo without interfering with APTT and PT. The bleeding time in mice and rats was significantly increased by CAE. The antiplatelet and anticoagulant effect observed in this study suggest that Juglans regia could have antithrombotic and/or thrombolytic activities and provide an alternative therapy against thrombotic complications related to cardiovascular diseases.

In order to reduce the risk of bleeding in patients on P2Y12 receptor inhibitors presenting for non-emergent coronary artery bypass grafting (CABG), current guidelines recommend a preoperative discontinuation period of at least three, five and seven days for ticagrelor, clopidogrel and prasugrel, respectively, to allow for recovery of platelet function. However, there is still substantial interinstitutional variation in preoperative management and relevant covariates of CABG-related bleeding are largely elusive so far.

Direct oral anticoagulants (DOACs) pose a great challenge for physicians in life-threatening bleeding events. The aim of this study was to test the efficacy of reversing the DOAC rivaroxaban using four-factor PCC (prothrombin complex concentrate), a non-specific reversing agent.

The treatment process of patients using warfarin is expected to be hindered during the COVID-19 pandemic. Therefore we investigated whether the time in therapeutic range (TTR) and bleeding complications were affected during the COVID-19 pandemic. 355 patients using warfarin were included between March 2019 to March 2021. Demographic parameters, INR (international normalized ratio), and bleeding rates were recorded retrospectively. The TTR value was calculated using Rosendaal's method. The mean age of the patients was 61 ± 12 years and 55% of them were female. The mean TTR value during the COVID-19 pandemic was lower than the pre-COVID-19 period (56 ± 21 vs 68 ± 21, P < 0.001). Among the patients, 41% had a lack of outpatient INR control. During the COVID-19 pandemic, 71 (20%) patients using VKA suffered bleeding. Among patients with bleeding, approximately 60% did not seek medical help and 6% of patients performed self-reduction of the VKA dose. During the COVID-19 pandemic, TTR values have decreased with the lack of monitoring. Furthermore, the majority of patients did not seek medical help even in case of bleeding.

Background The net clinical benefit of dual antiplatelet therapy (DAPT) reflects the paradoxical effects of an increased risk of bleeding and a reduced risk of major adverse cardiovascular events. A time-constrained approach to DAPT has been recently investigated in 5 multicenter trials including GLOBAL LEADERS, STOPDAPT2 (Short and Optimal Duration of Dual Antiplatelet Therapy After Everolimus-Eluting Cobalt-Chromium Stent-2), SMART-CHOICE, TWILIGHT (Ticagrelor With Aspirin or Alone in High-Risk Patients After Coronary Intervention), and TICO (Ticagrelor Monotherapy After 3 Months in the Patients Treated With New Generation Sirolimus Stent for Acute Coronary Syndrome). Methods and Results We undertook a pooled analysis of these trials to assess the overall associations between time-constrained P2Y12 inhibitor monotherapy (aspirin-free regimen) for bleeding events, major adverse cardiovascular events, and all-cause mortality as compared to standard care with DAPT for at least 12 months post-percutaneous coronary intervention. We implemented a DerSimonian and Laird random effects meta-analysis using the metafor package in R. 32 361 randomized trial participants, including 16 898 (52.2%) who had a history of acute coronary syndrome, underwent percutaneous coronary intervention, and had outcome data available. P2Y12 inhibitor monotherapy from 1 to 3 months was associated with a reduced risk for bleeding (hazard ratio [HR] 0.60; 95% CI, 0.45-0.81), including in the acute coronary syndrome group in which the magnitude of risk reduction was greatest (HR 0.50; 95% CI, 0.41-0.61). The estimates of the effect of P2Y12 inhibitor monotherapy on the HR were also favorable for major adverse cardiovascular events (0.88; 95% CI, 0.77-1.02) and all-cause mortality (0.85; 95% CI, 0.71-1.03). Conclusions Compared with DAPT for 12 months post-percutaneous coronary intervention, P2Y12 inhibitor monotherapy from 1 to 3 months substantially reduces the risk of major and fatal bleeding and, in addition, confers potentially protective effects, for major adverse cardiovascular events and all-cause mortality. Considering patient safety, the results support a strategy of DAPT for 1 to 3 months followed by aspirin-free P2Y12 inhibitor monotherapy.

The objective of this study was to explore the effects and underlying intervention mechanisms of Angelica water extract (AWE) on abnormal uterine bleeding (AUB) based on serum metabolomics. Firstly, the concentration of main active substances in AWE was determined and the chemical components were identified by UPLC-Q-Exactive Orbitrap-MS/MS. A drug-induced abortion model was established by mifepristone and misoprostol. After administration AWE (2.16 g/kg) for 7 days, the coagulation function, serum hormone levels, H&E staining, and immunohistochemistry observation of uterus were detected. In addition, serum metabolites profiles were performed on ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS). The contents of ferulic acid, senkyunolide A, and ligustilide in AWE were 0.7276, 0.0868, and 1.9908 mg/g, respectively. Twenty-six compounds were identified in AWE. It was found that AWE was effective in regulation of coagulation function and promoting endometrial recovery. Meanwhile, the levels of E2, Pg, and HCG and the expression of ERα, Erβ, and PR were down-regulated in AUB model and up-regulated by the treatment of AWE. Twenty-one potential biomarkers were eventually identified by multivariate statistical analysis. Study indicated that glycerophospholipid, sphingolipid, amino acids, retinol metabolism and primary bile acid biosynthesis were the main related metabolic pathways involved for the treatment of AUB by AWE. The results showed that AWE has potential therapeutic effect on AUB by altering the metabolic aberrations.

(p-BthTX-I)2 K, a dimeric analog peptide derived from the C-terminal region of phospholipase A2-like bothropstoxin-I (p-BthTX-I), is resistant to plasma proteolysis and inhibits severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strains with weak cytotoxic effects. Complications of SARS-CoV-2 infection include vascular problems and increased risk of thrombosis; therefore, studies to identify new drugs for treating SARS-CoV-2 infections that also inhibit thrombosis and minimize the risk of bleeding are required.

Over 75% of severely thrombocytopenic neonates receive platelet transfusions, though little evidence supports this practice, and only 10% develop major bleeding. In a recent randomized trial, giving platelet transfusions at a threshold platelet count of 50x109/L compared to a threshold of 25x109/L was associated with an increased risk of major bleeding or mortality. This finding highlights the need for improved and individualized guidelines on neonatal platelet transfusion, which require accurate prediction of bleeding risk. Therefore, the objective of this study was to develop a dynamic prediction model for major bleeding in thrombocytopenic preterm neonates. This model allows for calculation of bleeding risk at any time-point during the first week after the onset of severe thrombocytopenia. In this multicenter cohort study, we included neonates with a gestational age <34 weeks, admitted to a neonatal intensive care unit, who developed severe thrombocytopenia (platelet count <50x109/L). The study endpoint was major bleeding. We obtained predictions of bleeding risk using a proportional baselines landmark supermodel. Of 640 included neonates, 71 (11%) had a major bleed. We included the variables gestational age, postnatal age, intrauterine growth retardation, necrotizing enterocolitis, sepsis, platelet count and mechanical ventilation in the model. The median cross-validated c-index was 0.74 (interquartile range, 0.69-0.82). This is a promising dynamic prediction model for bleeding in this population that should be explored further in clinical studies as a potential instrument for supporting clinical decisions. The study was registered at www.clinicaltrials.gov (NCT03110887).

Stomach bleeding is a kind of gastrointestinal disease which can be diagnosed noninvasively by wireless capsule endoscopy (WCE). However, it requires much time for physicians to scan large amount of WCE images. Alternatively, computer-assisted bleeding localization systems are developed where color, edge, and intensity features are defined to distinguish lesions from normal tissues. This paper proposes a saliency-based localization system where three saliency maps are computed: phase congruency-based edge saliency map derived from Log-Gabor filter bands, intensity histogram-guided intensity saliency map, and red proportion-based saliency map. Fusing the three maps together, the proposed system can detect bleeding regions by thresholding the fused saliency map. Results demonstrate the accuracy of 98.97% for our system to mark bleeding regions.