Comparison of apixaban versus aspirin for the prevention of latent bioprosthetic aortic valve thrombosis: study protocol for a prospective randomized trial.

BACKGROUND: The optimal antithrombotic strategy early after aortic valve replacement surgery with a biological valve remains controversial due to lack of high-quality evidence. Either oral anticoagulants or acetylsalicylic acid should be considered for the first 3 months. Hypo-attenuated leaflet thickening on cardiac computed tomography has been associated with latent bioprosthetic valve thrombosis and may be prevented with anticoagulation. We hypothesize that anticoagulation with apixaban is superior to single antiplatelet therapy with acetylsalicylic acid in reducing hypo-attenuated leaflet thickening of bioprosthetic aortic valve prostheses. METHODS: In this prospective, open-label, randomized trial, patients undergoing isolated aortic valve replacement surgery with rapid deployment bioprosthetic valves will be randomized. The treatment group will receive 5 mg of apixaban twice a day for the first 3 months and 100 mg of acetylsalicylic acid thereafter. The control group will be administered 100 mg of acetylsalicylic acid once a day, indefinitely. After the 3-month treatment period, a contrast-enhanced electrocardiogram-gated cardiac computed tomography will be performed to identify hypo-attenuated leaflet thickening of the bioprosthetic valve. The primary objective of the study is to assess the impact of apixaban on the prevention of hypo-attenuated leaflet thickening at 3 months. The secondary and exploratory endpoints will be clinical outcomes and safety profiles of the two strategies. DISCUSSION: Antithrombotic therapy after aortic valve replacement is used to prevent valve thrombosis and systemic thromboembolism. Latent bioprosthetic valve thrombosis is a precursor of clinically significant prosthetic valve dysfunction or thromboembolic events. The hallmark feature of latent bioprosthetic valve thrombosis is hypo-attenuated leaflet thickening on cardiac computed tomography. Subclinical leaflet thrombosis occurs frequently in bioprosthetic aortic valves, more commonly in transcatheter than in surgical valves. There is no evidence on the effect of direct oral anticoagulants on the incidence of hypo-attenuated leaflet thickening after surgical aortic valve replacement with rapid deployment bioprostheses. TRIAL REGISTRATION: ClinicalTrials.gov NCT06184113. Registered on December 28, 2023.

New insights and novel perspectives in bileaflet mechanical heart valve prostheses thromboresistance.

BACKGROUND: Although well-known for their thromboresistance, bileaflet mechanical heart valves (BMHV) require lifelong anti-thrombotic therapy. This must be associated with a certain level of thrombogenicity. Since both thromboresistance and thrombogenicity are explained by the blood-artificial surface or liquid-solid interactions, the aim of the present study was to explore BMHV thromboresistance from new perspectives. The wettability of BMHV pyrolytic carbon (PyC) occluders was investigated in under-liquid conditions. The submerged BMHV wettability clarifies the mechanisms involved in the thromboresistance. METHODS: The PyC occluders of a SJM Regent™ BMHV were previously laser irradiated, to create a surface hierarchical nano-texture, featuring three nano-configurations. Additionally, four PyC occluders of standard BMHV (Carbomedics, SJM Regent™, Bicarbon™, On-X®), were investigated. All occluders were evaluated in under-liquid configuration, with silicon oil used as the working droplet, while water, simulating blood, was used as the surrounding liquid. The under-liquid droplet-substrate wetting interactions were analyzed using contact angle goniometry. RESULTS: All the standard occluders showed very low contact angle, reflecting a pronounced affinity for non-polar molecules. No receding of the contact line could be observed for the untreated occluders. The smallest static contact angle of around 61° could be observed for On-X® valve (the only valve made of full PyC). The laser-treated occluders strongly repelled oil in underwater conditions. A drastic change in their wetting behaviour was observed depending on the surrounding fluid, displaying a hydrophobic behaviour in the presence of air (as the surrounding medium), and showing instead a hydrophilic nature, when surrounded by water. CONCLUSIONS: BMHV "fear" water and blood. The intrinsic affinity of BMHV for nonpolar fluids can be translated into a tendency to repel polar fluids, such as water and blood. The blood-artificial surface interaction in BMHV is minimized. The contact between blood and BMHV surface is drastically reduced by polar-nonpolar Van der Waals forces. The "hydro/bloodphobia" of BMHV is intrinsically related to their chemical composition and their surface energy, thus their material: PyC indeed. Pertaining to thromboresistance, the surface roughness does not play a significant role. Instead, the thromboresistance of BMHV lies in molecular interactions. BMHV wettability can be tuned by altering the surface interface, by means of nanotechnology.

Palliative effects of carnosol on lung-deposited pollutant particles-induced thrombogenicity and vascular injury in mice.

The toxicity of inhaled particulate air pollution perseveres even at lower concentrations than those of the existing air quality limit. Therefore, the identification of safe and effective measures against pollutant particles-induced vascular toxicity is warranted. Carnosol is a bioactive phenolic diterpene found in rosemary herb, with anti-inflammatory and antioxidant actions. However, its possible protective effect on the thrombotic and vascular injury induced by diesel exhaust particles (DEP) has not been studied before. We assessed here the potential alleviating effect of carnosol (20 mg/kg) administered intraperitoneally 1 h before intratracheal (i.t.) instillation of DEP (20 µg/mouse). Twenty-four hours after the administration of DEP, various parameters were assessed. Carnosol administration prevented the increase in the plasma concentrations of C-reactive protein, fibrinogen, and tissue factor induced by DEP exposure. Carnosol inhibited DEP-induced prothrombotic effects in pial microvessels in vivo and platelet aggregation in vitro. The shortening of activated partial thromboplastin time and prothrombin time induced by DEP was abated by carnosol administration. Carnosol inhibited the increase in pro-inflammatory cytokines (interleukin-6 and tumor necrosis factor α) and adhesion molecules (intercellular adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin, and P-selectin) in aortic tissue. Moreover, it averted the effects of DEP-induced increase of thiobarbituric acid reactive substances, depletion of antioxidants and DNA damage in the aortic tissue. Likewise, carnosol prevented the decrease in the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) caused by DEP. We conclude that carnosol alleviates DEP-induced thrombogenicity and vascular inflammation, oxidative damage, and DNA injury through Nrf2 and HO-1 activation.

Clinical guidelines for prevention and treatment of CAT in Japan and other countries.

Cancer-associated thrombosis (CAT) is an important prognostic factor for an increasing number of cancer patients. Understanding of CAT among cancer care providers has grown in recent years, and guidelines for the prevention and treatment of CAT have been published in Japan and around the world. In this article, we introduce these major guidelines and discuss differences we identified between the Japanese guidelines and those of other countries, with a focus on problems and issues. Insurance coverage of low-molecular-weight heparin and indications for primary prevention with direct oral anticoagulants in particular require urgent consideration.

Evaluating thrombosis risk and patient-specific treatment strategy using an atherothrombosis-on-chip model.

Platelets play an essential role in thrombotic processes. Recent studies suggest a direct link between increased plasma glucose, lipids, and inflammatory cytokines with platelet activation and aggregation, resulting in an increased risk of atherothrombotic events in cardiovascular patients. Antiplatelet therapies are commonly used for the primary prevention of atherosclerosis. Transitioning from a population-based strategy to patient-specific care requires a better understanding of the risks and advantages of antiplatelet therapy for individuals. This proof-of-concept study evaluates the potential to assess an individual's risk of forming atherothrombosis using a dual-channel microfluidic model emulating multiple atherogenic factors in vitro, including high glucose, high cholesterol, and inflammatory cytokines along with stenosis vessel geometry. The model shows precise sensitivity toward increased plasma glucose, cholesterol, and tumour necrosis factor-alpha (TNF-α)-treated groups in thrombus formation. An in vivo-like dose-dependent increment in platelet aggregation is observed in different treated groups, benefiting the evaluation of thrombosis risk in the individual condition. Moreover, the model could help decide the effective dosing of aspirin in multi-factorial complexities. In the high glucose-treated group, a 50 µM dose of aspirin could significantly reduce platelet aggregation, while a 100 µM dose of aspirin was required to reduce platelet aggregation in the glucose-TNF-α-treated group, which proves the model's potentiality as a tailored tool for customised therapy.

On-X aortic valve replacement patients treated with low-dose warfarin and low-dose aspirin.

OBJECTIVES: To assess if warfarin targeted to international normalized ratio (INR) 1.8 (range 1.5-2.0) is safe for all patients with an On-X aortic mechanical valve. METHODS: This prospective, observational registry follows patients receiving warfarin targeted at an INR of 1.8 (range 1.5-2.0) plus daily aspirin (75-100 mg) after On-X aortic valve replacement. The primary end point is a composite of thromboembolism, valve thrombosis and major bleeding. Secondary end points include the individual rates of thromboembolism, valve thrombosis and major bleeding, as well as the composite in subgroups of home or clinic-monitored INR and risk categorization for thromboembolism. The control was the patient group randomized to standard-dose warfarin (INR 2.0-3.0) plus daily aspirin 81 mg from the PROACT trial. RESULTS: A total of 510 patients were enroled at 23 centres in the UK, USA and Canada. Currently, the median follow-up duration is 3.4 years, and median achieved INR is 1.9. The primary composite end point rate in the low INR patients is 2.31% vs 5.39% (95% confidence interval 4.12-6.93%) per patient-year in the PROACT control group, constituting a 57% reduction. Results are consistent in subgroups of home or clinic-monitored, and high-risk patients, with reductions of 56%, 57% and 57%, respectively. Major and total bleeding are decreased by 85% and 73%, respectively, with similar rates of thromboembolic events. No valve thrombosis occurred. CONCLUSIONS: Interim results suggest that warfarin targeted at an INR of 1.8 (range 1.5-2.0) plus aspirin is safe and effective in patients with an On-X aortic mechanical valve with or without home INR monitoring.

Prophylaxis of microvascular thrombosis using direct oral anticoagulants (DOAC) in microvascular free tissue transplantation - a pilot study.

INTRODUCTION: We conducted this pilot study to assess direct oral anticoagulants (DOACs) in the prevention of microvascular thrombosis. MATERIALS AND METHODS: Five patients undergoing microvascular free tissue transplantation received rivaroxaban or apixaban (depending on their home medication). We compared this group to 19 patients who received enoxaparin subcutaneously. We evaluated the rate of graft loss due to microvascular thrombosis and the number of transfusions administered intra- and postoperatively. RESULTS: There was no graft loss due to microvascular thrombosis in either of the groups. There was no significant difference in the number of intraoperative (study group mean 1.00 (SE 0.32) vs. control group mean 1.11 (SE 0.59); p = 0.876) and postoperative (study group mean 1.2 (SE 0.37) vs. control group mean 1.74 (SE 0.34); p = 0.310) red blood cell transfusions. CONCLUSION: Based on our results in this pilot study, DOACs can be used with microvascular flaps. Further studies with larger sample sizes should be performed to find an optimal medication regimen both for patients already taking DOACs and perhaps even for those not taking DOACs.

Nutrition and Cardiovascular Disease: The Potential Role of Marine Bioactive Proteins and Peptides in Thrombosis Prevention.

Thrombus and cardiovascular diseases pose a significant health threat, and dietary interventions have shown promising potential in reducing the incidence of these diseases. Marine bioactive proteins and peptides have been extensively studied for their antithrombotic properties. They can inhibit platelet activation and aggregation by binding to key receptors on the platelet surface. Additionally, they can competitively anchor to critical enzyme sites, leading to the inhibition of coagulation factors. Marine microorganisms also offer alternative sources for the development of novel fibrinolytic proteins, which can help dissolve blood clots. The advancements in technologies, such as targeted hydrolysis, specific purification, and encapsulation, have provided a solid foundation for the industrialization of bioactive peptides. These techniques enable precise control over the production and delivery of bioactive peptides, enhancing their efficacy and safety. However, it is important to note that further research and clinical studies are needed to fully understand the mechanisms of action and therapeutic potential of marine bioactive proteins and peptides in mitigating thrombotic events. The challenges and future application perspectives of these bioactive peptides also need to be explored.

The thrombotic risk in Cushing's syndrome-questions, answers, and the algorithm to consider in its assessment: part I-thrombotic risk not related to surgery.

Introduction: Recently, it has been reported that there is a great diversity in strategies used for thromboprophylaxis in patients with Cushing's syndrome (CS). An aim of this review was to discuss these practices in light of the existing data on the thrombotic risk in patients with CS and guidelines for medically ill patients. Methods: The four relevant topics and questions on thrombotic risk in CS were identified. The current guidelines on prevention and diagnosis of venous thromboembolism (VTE) were reviewed for the answers. An algorithm to consider in the assessment of the thrombotic risk in patients with CS was proposed. Results: To address both generic and CS-specific risk factors for VTE, the algorithm includes the stepwise approach consisting of Padua Score, urine free cortisol, and CS-VTE score, with no indication for routine thrombophilia testing in the prediction of an index VTE episode. Having confirmed VTE, selected patients require thrombophilia testing to aid the duration of anticoagulant treatment. The separate part of the algorithm is devoted to patients with ectopic adrenocorticotropic hormone syndrome in whom exclusion of VTE precedes introducing routine thromboprophylaxis to prevent VTE. The cancer-related VTE also prompts thromboprophylaxis, with the possible vessel invasion. The algorithm presents a unifactorial and multifactorial approach to exclude high-bleeding risks and safely introduce thromboprophylaxis with low-molecular-weight heparin. Summary: Our article is the first to present an algorithm to consider in the thrombotic risk assessment among patients with Cushing's syndrome as a starting point for a broader discussion in the environment. A plethora of factors affect the VTE risk in patients with CS, but no studies have conclusively evaluated the best thromboprophylaxis strategy so far. Future studies are needed to set standards of care.

Effect of corticosteroids on ischemia-reperfusion injury of deep inferior epigastric perforator flap after re-exploration for anastomosis thrombosis: A prospective randomized trial.

Patients undergoing breast reconstruction with the deep inferior epigastric perforator (DIEP) flap are at risk of arterial and venous thrombosis, necessitating flap salvage surgery. However, this carries the risk of ischemia-reperfusion injury (IRI) and potential significant partial or complete flap loss. The objective of this study was to evaluate the potential benefit of corticosteroids in reducing IRI related complications in DIEP flaps that are returned to the operation theater for attempted salvage after venous or arterial failure. A double-blinded prospective randomized study was conducted between January 2012 and January 2023 on patients scheduled for secondary unilateral breast reconstruction using the DIEP flap technique. Patients were included if they developed post-operative venous or arterial flap thrombosis and experienced DIEP flap IRI following operative take-back and anastomosis revision. The treatment group (TG) received a 5-day course of corticosteroids, while the control group (CG) did not receive any specific treatment. Forty-six patients were enrolled in the study. In the CG, two cases of total flap loss and eight cases of partial flap necrosis were observed, while the TG had only 1 case of partial flap necrosis (p < 0.05). The complete resolution of clinical signs of IRI occurred within 13 ± 2.1 days for the TG and 21 ± 3.5 days for the CG (p = 0.00001). The TG had a significantly shorter hospital stay (11.13 ± 0.38 days) compared with the CG (15.47 ± 1.27 days; p < 0.0001). Targeted corticosteroid therapy following a salvage procedure for vascular thrombosis in DIEP flaps has shown promise as an effective treatment for subsequent IRI. This approach may be considered as a viable option for managing IRI in free flaps. However, further studies involving a larger number of patients are required to substantiate our hypothesis.

[Mid-term analysis of prospective cohort study of rivaroxaban in preventing CRT in breast cancer].

Objective: To explore the efficacy and safety of Rivaroxaban in preventing catheter related thrombosis (CRT) in patients with breast cancer who are undergoing central venous catheter chemotherapy, and provide basis for making standardized prevention and treatment strategies. Methods: In this research, a prospective cohort study was adopted, and breast cancer patients who received central venous catheter chemotherapy in Sanhuan Cancer Hospital during September 2020 to March 2022 were selected as a treatment group to take the rivaroxaban anticoagulation therapy with 10 mg.po.qd for one month. The control group got no preventive anticoagulation therapy. Vascular ultrasound examination was taken to confirm the occurrence of CRT, and a chi-square test was done for comparison the disparity between the groups. Logistic regression was applied to analyze the univariate and multivariate factors for the formation of CRT. Results: In the research, a total of 235 patients were selected, and there were a total of 19 035 days of catheterization with 81 days of catheterization on average. While in the control group, the incidence of CRT was 28.0% (33/118), the incidence of CRT in the treatment group was 20.5% (24/117), the difference was no significant (P=0.183). Subgroup analysis results showed that the peripherally inserted central catheter (PICC) was performed in 165 cases with the CRT incidence of 18.2% (30/165) and thrombosis was mostly seen around axillary vein, accounting for 63.3%. Subclavian vein catheterization was performed in 63 cases with the CRT incidence of 39.7% (25/63), and thrombosis was mostly seen around subclavian vein, accounting for 88.0% (22/25). Implantable venous access port was implanted in 7 cases around subclavian vein and internal jugular vein with the CRT incidence of 28.6% (2/7). The patients who developed CRT within 30 days after catheterization accounted for 54.4% (31/57), 22.8% (13/57) in a period during 30 days and 60 days) and 22.8% (13/57) in a period during 60 days and 180 days). The diagnosed CRT patients had been treated with rivaroxaban 15 mg.bid.po for 3 months. During the 3 months, 100.0% of the thrombosis waned, 71.9% (41/57) of the thrombosis waned within 30 days, 19.3% (11/57) in a period during 30 and 60days and 8.8% (5/57) in a period during 60 days and 90 days. Univariate and multivariate analysis indicated that the risk of CRT in subclavian vein catheterization was higher than that in PICC, respectively (OR=2.898, 95% CI:1.386-6.056 P=0.005), and the type of catheterization was an independent factor for the formation of thrombosis. Safety analysis result showed that in the prevention of CRT, rivaroxaban treatment did not induce drug-related bleeding, liver function damage, bone marrow suppression or any other side effects. While CRT diagnosed patients were treated with anticoagulation, they kept the central venous catheter, and the infusion was smooth. These patients all finished the anti-tumor treatment as planned, and no abnormalities like new thrombosis or pulmonary embolism were observed. Conclusions: In the mid-term analysis, the proportion of Rivaroxaban in preventing anticoagulant CRT decreases, but it don't reach statistical significance. The sample size should be further increased for observation. Rivaroxaban is proved effective and very safe in the treatment of CRT, and does not affect the concurrent chemotherapy. Medical personnel should carry out the policy of "early prevention, early detection and early treatment" for CRT so as to improve the patients' quality of life.

In situ formed depot of elastin-like polypeptide-hirudin fusion protein for long-acting antithrombotic therapy.

Thrombosis, induced by abnormal coagulation or fibrinolytic systems, is the most common pathology associated with many life-threatening cardio-cerebrovascular diseases. However, first-line anticoagulant drugs suffer from rapid drug elimination and risk of hemorrhagic complications. Here, we developed an in situ formed depot of elastin-like polypeptide (ELP)-hirudin fusion protein with a prodrug-like feature for long-term antithrombotic therapy. Highly secretory expression of the fusion protein was achieved with the assistance of the Ffu312 tag. Integration of hirudin, ELP, and responsive moiety can customize fusion proteins with properties of adjustable in vivo retention and controllable recovery of drug bioactivity. After subcutaneous injection, the fusion protein can form a reservoir through temperature-induced coacervation of ELP and slowly diffuse into the blood circulation. The biological activity of hirudin is shielded due to the N-terminal modification, while the activated key proteases upon thrombus occurrence trigger the cleavage of fusion protein together with the release of hirudin, which has antithrombotic activity to counteract thrombosis. We substantiated that the optimized fusion protein produced long-term antithrombotic effects without the risk of bleeding in multiple animal thrombosis models.

Efficacy of Micronized Purified Flavonoid Fraction in the Posthemorrhoidectomy Period Trial: Open-Label Randomized Controlled Trial.

BACKGROUND: Frequent early postoperative complications of hemorrhoidectomy are thrombosis and edema of mucocutaneous "bridges." OBJECTIVE: This study aimed to investigate the efficacy of micronized purified flavonoid fraction in preventing complications after elective hemorrhoidectomy. DESIGN: Prospective unicentral open-label randomized controlled trial. SETTINGS: 2021-2022 at the Clinic of Colorectal and Minimally Invasive Surgery at Sechenov University (Moscow, Russia). PATIENTS: Patients who underwent hemorrhoidectomy for grade III and IV hemorrhoids. INTERVENTIONS: After hemorrhoidectomy, patients were randomly assigned either to standard treatment (peroral nonsteroid anti-inflammatory drugs and local anesthetics, topical steroids, psyllium, warm sitz baths, and nifedipine gel), referred to as the control group, or to standard treatment with micronized purified flavonoid fraction, referred to as the study group, and followed up for 60 days. MAIN OUTCOME MEASURES: Thrombosis or edema of mucocutaneous bridges and pain intensity on a visual analog scale оn postoperative days 1-7, 14, 21, and 30; quality of life and patient-assessed treatment effect оn postoperative days 1, 3, 7, 21, and 30; and perianal skin tags оn postoperative day 60. RESULTS: The data from 50 patients were analyzed (25 in each group). The visual analog scale demonstrated no differences between groups in each follow-up point. Compared to the control group, the patients in the study group had a significantly higher patient-assessed treatment effect оn postoperative days 1, 3, 7, 21, and 30 and a significantly lower rate of thrombosis or edema of mucocutaneous bridges оn postoperative days 1-7 and 14. Patients in the study group had significantly lower rates of perianal skin tags. LIMITATIONS: Unicenter open-label design. CONCLUSIONS: Micronized purified flavonoid fraction in the posthemorrhoidectomy period is an effective adjunct to standard treatment that helps reduce the rate of thrombosis and edema of mucocutaneous bridges, improves patient-assessed treatment effect, and prevents postoperative perianal skin tags formation. Micronized purified flavonoid fraction in the posthemorrhoidectomy period is not associated with additional pain relief in comparison with nonmicronized purified flavonoid fraction standard treatment. See Video Abstract . EFICACIA DE LA FRACCIN DE FLAVONOIDES PURIFICADA MICRONIZADA EN EL PERODO POSTERIOR A LA HEMORROIDECTOMA ENSAYO MOST ENSAYO CONTROLADO, ALEATORIZADO, ABIERTO: ANTECEDENTES:Una complicación postoperatoria temprana frecuente de la hemorroidectomía es la trombosis y el edema de los "puentes" mucocutáneos.OBJETIVO:Investigamos la eficacia de la fracción de flavonoides purificada micronizada en la prevención de complicaciones después de una hemorroidectomía electiva.DISEÑO:Ensayo controlado aleatorio, prospectivo, unicentral, abierto.AJUSTES:2021-2022 Clínica de Cirugía Colorrectal y Mínimamente Invasiva Universidad Sechenov (Moscú, Rusia).PACIENTES:Pacientes después de hemorroidectomía, que se realizó para hemorroides de grado III-IV.INTERVENCIONES:Después de la hemorroidectomía, los pacientes fueron asignados aleatoriamente al tratamiento estándar (antiinflamatorios no esteroides perorales y anestésicos locales, esteroides tópicos, psyllium, baños de asiento tibios, gel de nifedipina) - grupo de control, o al tratamiento estándar con flavonoide purificado micronizado. fracción (grupo de estudio) y seguido durante 60 días.RESULTADOS DE MEDIDAS PRINCIPALES:Trombosis o edema de puentes mucocutáneos e intensidad del dolor en una escala analógica visual entre el 1.º, 7.º, 14.º, 21.º y 30.º día postoperatorio; calidad de vida y efecto del tratamiento evaluado por el paciente el día 1, 3, 7, 21 y 30 del postoperatorio; Marcas cutáneas perianales en el día 60 del postoperatorio.RESULTADOS:Se analizaron los datos de 50 pacientes (25 en cada grupo). La escala analógica visual no demostró diferencias entre grupos en cada punto de seguimiento. En comparación con el grupo de control, los pacientes en el grupo de estudio tuvieron un efecto del tratamiento evaluado por el paciente significativamente mayor en los días 1, 3, 7, 21 y 30 después de la operación, una tasa significativamente menor de trombosis o edema de los puentes mucocutáneos en los días 1, 7 y 14.. Los pacientes del grupo de estudio tuvieron tasas significativamente más bajas de marcas en la piel perianal.LIMITACIONES:Diseño Unicenter de etiqueta abierta.CONCLUSIONES:La fracción de flavonoides purificada micronizada en el período posterior a la hemorroidectomía es un complemento eficaz del tratamiento estándar que ayuda a reducir la tasa de trombosis y edema de los puentes mucocutáneos, mejora el efecto del tratamiento evaluado por el paciente y previene la formación de marcas cutáneas perianales posoperatorias. La fracción de flavonoides purificados micronizados en el período posterior a la hemorroidectomía no se asocia con un alivio adicional del dolor en comparación con el tratamiento estándar con la fracción de flavonoides purificados no micronizados. (Traducción-Yesenia Rojas-Khalil ).

Improvement of thrombosis management in patients with cancer: a practical consensus document of recommendations for cancer-associated thrombosis patients' healthcare in Spain.

Cancer patients are at risk of venous thromboembolism (VTE), its recurrence, but also at risk of bleeding while anticoagulated. In addition, cancer therapies have been associated to increased VTE risk. Guidelines for VTE treatment in cancer patients recommend low molecular weight heparins (LMWH) or direct oral anticoagulants (DOAC) for the initial treatment, DOAC for VTE short-term treatment, and LMWH or DOAC for VTE long-term treatment. This consensus article arises from a collaboration between different Spanish experts on cancer-associated thrombosis. It aims to reach an agreement on a practical document of recommendations for action allowing the healthcare homogenization of cancer-associated thrombosis (CAT) patients in Spain considering not only what is known about VTE management in cancer patients but also what is done in Spanish hospitals in the clinical practice. The text summarizes the current knowledge and available evidence on the subject in Spain and provides a series of practical recommendations for CAT management and treatment algorithms to help clinicians to manage CAT over time.

Urokinase prophylactic anticoagulation in children with nephrotic syndrome: a multicenter retrospective cohort study.

OBJECTIVE: To analyze the clinical effect of urokinase on the prevention of thrombosis in children with primary nephrotic syndrome. METHODS: A total of 370 children diagnosed with primary nephrotic syndrome (PNS) in the Children's Hospital of Soochow University and Zibo Maternal and Child Health Hospital from January 2018 to December 2022 were selected as the research objects. The patients were divided into a urokinase adjuvant therapy group and non-urokinase adjuvant therapy group according to the application of drugs. The clinical data of the children were collected, including sex, age, drug application, bleeding during treatment, and telephone follow-up, to record whether thromboembolism occurred in the acute stage and remission stage. The clinical pattern of PNS, renal biopsy, histopathological type, and related laboratory indexes before and after treatment were recorded. RESULTS: A total of 313 patients were treated with urokinase and 57 patients were not. More thrombotic events was observed in non-urokinase group compared to the urokinase group(2 versus 0 episodes, p = 0.02). The thrombotic events observed included one patient had pulmonary embolism combined with right ventricular thrombosis, and another had intracranial venous thrombosis. More minor bleeding events occurred in urokinase group compared to the non-urokinase group(7 versus 1 episodes, p = 1.0). No major bleeding events occurred in either group. CONCLUSION: The rational prophylactic use of urokinase anticoagulation in children with PNS can prevent the formation of thromboembolism and has good safety.

Prolonged Proton Pump Inhibitor Use and Thrombohemorrhagic Risk in Essential Thrombocythemia and Polycythemia Vera Patients Treated with Long-Term Aspirin: A Pilot Study.

INTRODUCTION: Proton pump inhibitors (PPIs) are known to decrease the risk of gastrointestinal (GI) bleeding. However, concerns have been raised regarding the potential pharmacodynamic interactions of PPIs and antiplatelet drugs with respect to cardiovascular risk. Patients with BCR::ABL1-negative myeloproliferative neoplasms (MPNs), essential thrombocythemia (ET), and polycythemia vera (PV) often suffer from peptic ulcer disease (PUD) and frequently receive low-dose aspirin due to an intrinsically high thrombotic risk. METHOD: This retrospective multicenter study from a community setting investigated whether continuous PPI use may affect thrombohemorrhagic risk in ET and PV patients treated with long-term aspirin. RESULTS: Ninety-four aspirin-treated MPN patients (ET = 36, PV = 58) were included; median age was 69.5 years (range 21-92) and 40 (42.6%) were males. Nineteen (20.2%) patients continuously received PPIs and pantoprazole (n = 15, 78.9%) was the most frequently received PPI. PV phenotype (p = 0.085), male sex (p = 0.011), and prior thrombosis (p = 0.005) were associated with PPI use, whereas no correlations were found with respect to age, disease risk, splenomegaly, mutational status, constitutional symptoms, cardiovascular risk factors, cytoreductive treatment, or any of the blood cell counts (p > 0.050 for all analyses). The median follow-up time was 55.5 months; 19 (20.2%) thrombotic and 13 (13.8%) bleeding events occurred during this time. The use of PPIs was not associated with an increased risk of thrombosis (p = 0.158) or overall bleeding (p = 0.229) and none of the patients treated with PPIs experienced GI bleeding. CONCLUSIONS: Considering that Helicobacter pylori infection and PUD are quite frequent in ET and PV patients, these preliminary results may provide some reassurance to physicians regarding the absence of thrombohemorrhagic risk associated with prolonged PPI use in MPN patients treated with long-term aspirin. Our observations may be even more important in the light of recent evidence suggesting suboptimal platelet inhibition in ET with once-daily when compared to twice- or triple-daily aspirin which may also cause more abdominal discomfort. Limitations of this study are its retrospective design, limited number of patients included, and the lack of pharmacodynamic and pharmacokinetic assessments.

Photo-induced universal modification of small-diameter decellularized blood vessels with a hemocompatible peptide improves in vivo patency.

Decellularized vessels (DVs) have the potential to serve as available grafts for small-diameter vascular (<6 mm) reconstruction. However, the absence of functional endothelia makes them likely to trigger platelet aggregation and thrombosis. Luminal surface modification is an efficient approach to prevent thrombosis and promote endothelialization. Previously, we identified a hemocompatible peptide, HGGVRLY, that showed endothelial affinity and antiplatelet ability. By conjugating HGGVRLY with a phenylazide group, we generated a photoreactive peptide that can be modified onto multiple materials, including non-denatured extracellular matrices. To preserve the natural collagen of DVs as much as possible, we used a lower ultrahydrostatic pressure than that previously reported to prepare decellularized grafts. The photoreactive HGGVRLY peptide could be modified onto DV grafts via UV exposure for only 2 min. Modified DVs showed improved endothelial affinity and antiplatelet ability in vitro. When rat abdominal aortas were replaced with DVs, modified DVs with more natural collagen demonstrated the highest patent rate after 10 weeks. Moreover, the photoreactive peptide remained on the lumen surface of DVs over two months after implantation. Therefore, the photoreactive peptide could be efficiently and sustainably modified onto DVs with more natural collagens, resulting in improved hemocompatibility. STATEMENT OF SIGNIFICANCE: We employed a relatively lower ultrahydrostatic pressure to prepare decellularized vessels (DVs) with less denatured collagens to provide a more favorable environment for cell migration and proliferation. The hemocompatibility of DV luminal surface can be enhanced by peptide modification, but undenatured collagens are difficult to modify. We innovatively introduce a phenylazide group into the hemocompatible peptide HGGVRLY, which we previously identified to possess endothelial affinity and antiplatelet ability, to generate a photoreactive peptide. The photoreactive peptide can be efficiently and stably modified onto DVs with more natural collagens. DV grafts modified with photoreactive peptide exhibit enhanced in vivo patency. Furthermore, the sustainability of photoreactive peptide modification on DV grafts within bloodstream is evident after two months of transplantation.

Finding a common definition of heparin resistance in adult cardiac surgery: communication from the ISTH SSC subcommittee on perioperative and critical care thrombosis and hemostasis.

Ensuring adequate anticoagulation for patients requiring cardiac surgery and cardiopulmonary bypass (CPB) is important due to the adverse consequences of inadequate anticoagulation with respect to bleeding and thrombosis. When target anticoagulation is not achieved with typical doses, the term heparin resistance is routinely used despite the lack of uniform diagnostic criteria. Prior reports and guidance documents that define heparin resistance in patients requiring CPB and guidance documents remain variable based on the lack of standardized criteria. As a result, we conducted a review of clinical trials and reports to evaluate the various heparin resistance definitions employed in this clinical setting and to identify potential standards for future clinical trials and clinical management. In addition, we also aimed to characterize the differences in the reported incidence of heparin resistance in the adult cardiac surgical literature based on the variability of both target-activated clotting (ACT) values and unfractionated heparin doses. Our findings suggest that the most extensively reported ACT target for CPB is 480 seconds or higher. Although most publications define heparin resistance as a failure to achieve this target after a weight-based dose of either 400 U/kg or 500 U/kg of heparin, a standardized definition would be useful to guide future clinical trials and help improve clinical management. We propose the inability to obtain an ACT target for CPB of 480 seconds or more after 500 U/kg as a standardized definition for heparin resistance in this setting.

Systemic Arterial and Venous Thrombotic Events Associated With Anti-Vascular Endothelial Growth Factor Injections: A Meta-Analysis.

PURPOSE: To compare the risk of systemic arteriovenous thrombotic events between intravitreal anti-vascular endothelial growth factor (anti-VEGF) and sham injections. DESIGN: Random-effects meta-analysis. METHODS: A systematic search was performed on OVID MEDLINE, Embase, and Cochrane Library from January 2005 to August 2023. Our inclusion criteria were randomized controlled trials (RCTs) reporting on systemic arteriovenous events for standard dose intravitreal anti-VEGF agents for any indication. RESULTS: A total of 20 RCTs reporting on 12,833 eyes were included. There was no significant difference in the risk of any thrombotic event between bevacizumab 1.25 mg and ranibizumab 0.5 mg (Risk ratio (RR) = 0.96, 95% CI = 0.52-1.75, P = .89). There was no significant difference between bevacizumab and ranibizumab when restricting to arterial thrombotic events (RR= 0.88, 95% CI = 0.60-1.30, P = .53) or venous thrombotic events (RR = 1.99, 95% CI =86 0.68-5.82], P = .21). The risk of arterial thrombotic events was similar between aflibercept and bevacizumab (RR = 1.11, 95% CI = 0.60-2.07, P = .74), between aflibercept and ranibizumab (RR= 0.77, 95% CI = 0.49-1.21, P = .26), between brolucizumab and aflibercept (RR= 0.67, 95% CI = 0.32-1.38, P = .27), and between aflibercept and faricimab (RR = 0.96, 95% CI = 0.43-2.17, P = .93). Compared to sham, neither dose of ranibizumab (0.5 mg or 0.3 mg) showed a higher risk of arterial thrombotic events. CONCLUSIONS: There was a similar risk of systemic arteriovenous thrombotic adverse events between anti-VEGF agents and between ranibizumab and sham injections.

Pharmacological and clinical appraisal of factor XI inhibitor drugs.

The evolution of anticoagulation therapy, from vitamin K antagonists to the advent of direct oral anticoagulants (DOACs) almost two decades ago, marks significant progress. Despite improved safety demonstrated in pivotal trials and post-marketing observations, persistent concerns exist, particularly regarding bleeding risk and the absence of therapeutic indications in specific subgroups or clinical contexts. Factor XI (FXI) has recently emerged as a pivotal contributor to intraluminal thrombus formation and growth, playing a limited role in sealing vessel wall injuries. Inhibiting FXI presents an opportunity to decouple thrombosis from haemostasis, addressing concerns related to bleeding events while safeguarding against thromboembolic events. Notably, FXI inhibition holds promise for patients with end-stage renal disease or cancer, where clear indications for DOACs are currently lacking. Various compounds have undergone design, testing, and progression to phase 2 clinical trials, demonstrating a generally favourable safety and tolerability profile. However, validation through large-scale phase 3 trials with sufficient power to assess both safety and efficacy outcomes is needed. This review comprehensively examines FXI inhibitors, delving into individual classes, exploring their pharmacological properties, evaluating the latest evidence from randomized trials, and offering insights into future perspectives.