BACKGROUND: Literature on the preferred anticoagulant for treating left ventricular thrombus (LVT) is lacking. Thus, our objective was to compare the efficacy of DOACs versus warfarin in treating LVT.
METHODS: Databases were searched for RCTs and adjusted observational studies that compared DOAC versus warfarin through March 2024. The primary efficacy outcomes of interest were LVT resolution, systemic embolism, composite of stroke, and TIA. The primary safety outcomes encompassed all-cause mortality and bleeding events.
RESULTS: Our meta-analysis including 31 studies demonstrated that DOAC use was associated with higher odds of thrombus resolution (OR: 1.08, 95% CI: 0.86-1.31, p: 0.46). A statistically significant reduction in the risk of stroke/TIA was observed in the DOAC group versus the warfarin group (OR: 0.65, 95% CI: 0.48-0.89, p: 0.007). Furthermore, statistically significant reduced risks of all-cause mortality (OR: 0.68, 95% CI: 0.47-0.98, p: 0.04) and bleeding events (OR: 0.70, 95% CI: 0.55-0.89, p: 0.004) were observed with DOAC use as compared to warfarin use.
CONCLUSIONS: Compared to VKAs, DOACs are noninferior as the anticoagulant of choice for LVT treatment. However, further studies are warranted to confirm these findings.

Unfractionated heparin (UFH) and its low-molecular-weight fragments (LMWH) are widely used as anticoagulants for surgical procedures and extracorporeal blood purification therapies such as cardiovascular surgery and dialysis. The anticoagulant effect of heparin is essential for the optimal execution of extracorporeal blood circulation. However, at the end of these procedures, to avoid the risk of bleeding, it is necessary to neutralize it. Currently, the only antidote for heparin neutralization is protamine sulphate, a highly basic protein which constitutes a further source of serious side events and is ineffective in neutralizing LMWH. Furthermore, dialysis patients, due to the routine administration of heparin, often experience serious adverse effects, among which HIT (heparin-induced thrombocytopenia) is one of the most severe. For this reason, the finding of new heparin antagonists or alternative methods for heparin removal from blood is of great interest. Here, we describe the synthesis and characterization of a set of biocompatible macroporous cryogels based on poly(2-hydroxyethyl methacrylate) (pHEMA) and L-lysine with strong filtering capability and remarkable neutralization performance with regard to UFH and LMWH. These properties could enable the design and creation of a filtering device to rapidly reverse heparin, protecting patients from the harmful consequences of the anticoagulant.

We recently reported the potential application of recombinant prothrombin activator ecarin (RAPClot™) in blood diagnostics. In a new study, we describe RAPClot™ as an additive to develop a novel blood collection prototype tube that produces the highest quality serum for accurate biochemical analyte determination. The drying process of the RAPClot™ tube generated minimal effect on the enzymatic activity of the prothrombin activator. According to the bioassays of thrombin activity and plasma clotting, γ-radiation (>25 kGy) resulted in a 30-40% loss of the enzymatic activity of the RAPClot™ tubes. However, a visual blood clotting assay revealed that the γ-radiation-sterilized RAPClot™ tubes showed a high capacity for clotting high-dose heparinized blood (8 U/mL) within 5 min. This was confirmed using Thrombelastography (TEG), indicating full clotting efficiency under anticoagulant conditions. The storage of the RAPClot™ tubes at room temperature (RT) for greater than 12 months resulted in the retention of efficient and effective clotting activity for heparinized blood in 342 s. Furthermore, the enzymatic activity of the RAPClot™ tubes sterilized with an electron-beam (EB) was significantly greater than that with γ-radiation. The EB-sterilized RAPClot™ tubes stored at RT for 251 days retained over 70% enzyme activity and clotted the heparinized blood in 340 s after 682 days. Preliminary clinical studies revealed in the two trials that 5 common analytes (K, Glu, lactate dehydrogenase (LD), Fe, and Phos) or 33 analytes determined in the second study in the γ-sterilized RAPClot™ tubes were similar to those in commercial tubes. In conclusion, the findings indicate that the novel RAPClot™ blood collection prototype tube has a significant advantage over current serum or lithium heparin plasma tubes for routine use in measuring biochemical analytes, confirming a promising application of RAPClot™ in clinical medicine.

BACKGROUND: We aimed to summarise the existing knowledge regarding antithrombotic medications following surgical aortic valve replacement (SAVR) using a biological valve prosthesis.
METHODS: We performed a meta-analysis of studies that reported the results of using antithrombotic medication to prevent thromboembolic events after SAVR using a biological aortic valve prosthesis and recorded the outcomes 12 months after surgery. Since no randomised controlled trials were identified, observational studies were included. The analyses were conducted separately for periods of 0-12 months and 3-12 months after surgery. A random effects model was used to calculate pooled outcome event rates and 95% confidence intervals (CIs).
RESULTS: The search yielded eight eligible observational studies covering 6727 patients overall. The lowest 0- to 12-month mortality was observed in patients with anticoagulation (2.0%, 95% CI 0.4-9.7%) and anticoagulation combined with antiplatelet therapy (2.2%, 95% CI 0.9-5.5%), and the highest was in patients without antithrombotic medication (7.3%, 95% CI 3.6-14.2%). Three months after surgery, mortality was lower in anticoagulant patients (0.5%, 95% CI 0.1-2.6%) than in antiplatelet patients (3.0%, 95% CI 1.2-7.4%) and those without antithrombotics (3.5%, 95% CI 1.3-9.3%). There was no eligible evidence of differences in stroke rates observed among medication strategies. At 0- to 12-month follow-up, all antithrombotic treatment regimens resulted in an increased bleeding rate (antiplatelet 4.2%, 95% CI 2.9-6.1%; anticoagulation 7.5%, 95% CI 3.8-14.4%; anticoagulation combined with antiplatelet therapy 8.3%, 95% CI 5.7-11.8%) compared to no antithrombotic medication (1.1%, 95% CI 0.4-3.4%). At 3- to 12-month follow-up, there was up to an eight-fold increase in the bleeding rate in patients with anticoagulation combined with antiplatelet therapy when compared to those with no antithrombotic medication. Overall, the evidence certainty was ranked as very low.
CONCLUSIONS: Although this meta-analysis reveals that anticoagulation therapy has a beneficial tendency in terms of mortality at 1 year after biological SAVR and suggests potential advantages in continuing anticoagulation beyond 3 months, it is limited by very low evidence certainty. The imperative for cautious interpretation and the urgent need for more robust randomised research underscore the complexity of determining optimal antithrombotic strategies in this patient population.

OBJECTIVE: To estimate the strength of association between exposure to selected classes of prescribed medications and the risk of developing iron deficiency anaemia (IDA), specifically considering oral anticoagulants (OACs), antidepressants, antiplatelet agents, proton pump inhibitors (PPIs) and non-steroidal anti-inflammatories.
METHODS: A case-control study involving the analysis of community repeat prescriptions among subjects referred with IDA, and unmatched controls referred as gastroenterology fast-tracks for other indications. Multivariable logistic regression modelling was used to calculate ORs for the association between IDA presentation and each medication class, adjusted for age, sex and coprescribing. For those classes showing significance, it was also used to calculate risk differences between those in the IDA group with or without haemorrhagic lesions on investigation.
RESULTS: A total of 1210 cases were analysed-409 in the IDA group, and 801 in the control group. Significant associations were identified between presentation with IDA and long-term exposure to PPIs (OR 3.29, 95% CI: 2.47 to 4.41, p<0.001) and to OACs (OR 2.04, 95% CI: 1.29 to 3.24, p=0.002). IDA was not associated with long-term exposure to any of the other three drug classes. In contrast to the relationship with PPIs, the association with OACs was primarily in the IDA sub-group with haemorrhagic lesions.
CONCLUSIONS: Long-term exposure to PPIs and OACs are independently associated with the risk of developing IDA. There are grounds for considering that these associations may be causal, though the underlying mechanisms probably differ.

BACKGROUND: Left ventricular assist devices (LVADs) have emerged as a successful treatment option for patients with end-stage heart failure. Compared with the best medical therapy, LVADs improve survival and enhance functional capacity and quality of life. However, two major complications compromise this patient population\'s outcomes: thrombosis and bleeding. Despite technological innovations and better hemocompatibility, these devices alter the rheology, triggering the coagulation cascade and, therefore, require antithrombotic therapy. Anticoagulation and antiplatelet therapies represent the current standard of care. Still, inconsistency in the literature exists, especially whether antiplatelet therapy is required, whether direct oral anticoagulants can replace vitamin K antagonists and even whether phosphodiesterase type 5 inhibitors with their antithrombotic effects could be added to the regimen of anticoagulation.
METHODS: We will perform a living systematic review with network meta-analysis and indirect comparison between current antithrombotic therapies, which have and have not been directly compared within clinical trials and observational studies. We will systematically search the following electronic sources: Cochrane Central Register of Controlled Trials (CENTRAL), Medical Literature Analysis and Retrieval System Online (MEDLINE) and Excerpta Medica Database (EMBASE). We will exclusively examine studies published in English from 2016 to the present. Studies conducted before 2016 will be omitted since our primary focus is evaluating continuous flow devices. Two independent reviewers will assess the articles by title, abstract and full text; any disagreement will be resolved through discussion, and a third reviewer will be involved if necessary. The Cochrane Risk of Bias tool will be used to assess the risk of bias. We will then conduct a pairwise meta-analysis; if the assumption of transitivity is satisfied, we will proceed with network meta-analysis using Bayesian methodology.
BACKGROUND: Formal ethical approval is not required as no primary data are collected. This systematic review and network meta-analysis will delineate the risks of stroke, thromboembolic events, pump thrombosis, gastrointestinal bleeding and mortality in patients equipped with LVADs who are subjected to various antithrombotic regimens. The findings will be disseminated via a peer-reviewed publication and presented at conference meetings. This will enhance clinical practice and guide future research on anticoagulation strategies within this distinct patient cohort.
UNASSIGNED: CRD42023465288.

BACKGROUND: Unfractionated heparin (UFH) is used in most centres for extracorporeal membrane oxygenation (ECMO) anticoagulation. When standard doses do not achieve desired target values, heparin resistance is reported, most commonly defined as doses of UFH >35,000 IU/day.
OBJECTIVE: To study the incidence of heparin resistance and its association with thromboembolic complications in patients requiring ECMO support.
METHODS: In this observational cohort study, we included adults who received venovenous (VV), venoarterial (VA) ECMO, and extracorporeal CO2-removal (ECCO2R) between January 2010 and May 2022. Main risk factor was heparin resistance (UFH >35,000 IU/day or >20 IU/kg/h), the outcome was thromboembolism. Multivariable Poisson regression was used to estimate the effects of heparin resistance, adjusted for several clinical variables on the thromboembolism rate per 100 ECMO patient-days.
RESULTS: Of the 197 patients included, 33 (16.8%) required UFH >35,000 IU/day, and 14 (7.1%) required >20 IU/kg/h. Thromboembolic complications occurred at a rate of 5.89/100 ECMO days. Heparin resistance was not associated with thromboembolic events (incidence rate ratio (IRR) 0.93, 95% confidence interval (CI) 0.14 to 5.82), whereas COVID-19 (IRR 2.33, CI 1.4 to 3.96, p<0.001) and ECMO type (VA ECMO: IRR 2.29, CI 1.34 to 3.92, p=0.002; ECCO2R: IRR 2.89, CI 1.46 to 5.59, p=0.002; reference VV ECMO) were significantly associated with the risk of thromboembolic events.
CONCLUSIONS: A significant proportion of patients fulfilled the common definition of heparin resistance. However, this did not influence the occurrence of thromboembolic events.

OBJECTIVE: Atezolizumab and bevacizumab (Atezo/Bev) combination immunotherapy regimens and direct oral anticoagulants (DOACs) are both associated with bleeding. Therefore, combining Atezo/Bev regimens with DOACs may exacerbate the bleeding risk. This study investigated the feasibility of the Atezo/Bev regimen in patients taking DOACs.
METHODS: This retrospective study included 141 patients with unresectable hepatocellular carcinoma (HCC) or advanced lung cancer (LC) treated with Atezo/Bev regimens. Patients who used antithrombotic agents other than DOACs were excluded. Bleeding events during the Atezo/Bev regimen were analyzed.
RESULTS: The incidence rates of bleeding of any grade in the DOAC (n = 11) and no antithrombotic agent (NAA) (n = 130) groups were 9.1% and 10.8%, respectively, with no significant differences. Moreover, no significant difference was found in the frequency of bleeding of grade ≥3 between the DOAC and NAA groups. No patients in the DOAC group discontinued the Atezo/Bev regimen because of severe bleeding. Although serum albumin levels, with a hazard ratio (HR) of 0.298 (95% confidence interval [CI]: 0.105-0.847), independently contributed to bleeding events (p = 0.023), DOAC administration did not (HR: 1.357; 95% CI: 0.157-10.54; p = 0.770). Among only patients with HCC (n = 59), none of the five patients taking DOACs experienced bleeding events. A high albumin-bilirubin score (HR: 9.083, 95% CI: 1.118-73.76) was associated with bleeding events (p = 0.039).
CONCLUSIONS: DOACs did not have a considerable effect on bleeding events in the Atezo/Bev regimens for HCC or LC. Under careful surveillance for bleeding, Atezo/Bev regimens may be feasible in patients receiving DOACs.

BACKGROUND: This study evaluates the cost-effectiveness of Apixaban and Rivaroxaban, compared to Warfarin, for stroke prevention in patients with non-valvular atrial fibrillation in Iran.
METHODS: A Markov model with a 30-year time horizon was employed to simulate and assess different treatment strategies\' cost-effectiveness. The study population comprised Iranian adults with NVAF, identified through specialist consultations, hospital visits, and archival record reviews. Direct medical costs, direct nonmedical, and indirect costs were included. Quality-adjusted life years (QALY) were assessed using an EQ-5D questionnaire. This study utilized a cost-effectiveness threshold of $11 134 per QALY.
RESULTS: Apixaban demonstrated superior cost-effectiveness compared to Rivaroxaban and Warfarin. Over 30 years, total costs were lower in the Apixaban and Rivaroxaban groups compared to the Warfarin group ($126.18 and $109.99 vs. $150.49). However, Apixaban showed higher total QALYs gained compared to others (0.134 vs. 0.133 and 0.116). The incremental cost-effectiveness ratio for comparing Apixaban to Warfarin was calculated at -1332.83 cost per QALY, below the threshold of $11 134, indicating Apixaban\'s cost-effectiveness. Sensitivity analyses confirmed the robustness of the findings, with ICER consistently remaining below the threshold. Over 5 years (2024-2028) of Apixaban usage, the incremental cost starts at USD 70 250 296 in the first year and gradually rises to USD 71 770 662 in the fifth year. DSA and PSA were assessed to prove the robustness of the results.
CONCLUSIONS: This study shows that Apixaban is a cost-effective option for stroke prevention in non-valvular atrial fibrillation patients in Iran compared to Warfarin.

Despite their evolutionary novelty, lizard venoms are much less studied in comparison to the intense research on snake venoms. While the venoms of helodermatid lizards have long been assumed to be for defensive purposes, there is increasing evidence of toxic activities more useful for predation than defence (such as paralytic neurotoxicity). This study aimed to ascertain the effects of Heloderma, Lanthanotus, and Varanus lizard venoms on the coagulation and cardiovascular systems. Anticoagulant toxicity was demonstrated for the Varanus species studied, with the venoms prolonging clotting times in human and bird plasma due to the destructive cleavage of fibrinogen. In contrast, thromboelastographic analyses on human and bird plasmas in this study demonstrated a procoagulant bioactivity for Heloderma venoms. A previous study on Heloderma venom using factor-depleted plasmas as a proxy model suggested a procoagulant factor was present that activated either Factor XI or Factor XII, but could not ascertain the precise target. Our activation studies using purified zymogens confirmed FXII activation. Comparisons of neonate and adult H. exasperatum, revealed the neonates to be more potent in the ability to activate FXII, being more similar to the venom of the smaller species H. suspectum than the adult H. exasperatum. This suggests potent FXII activation a basal trait in the genus, present in the small bodied last common ancestor. This also indicates an ontogenetic difference in prey preferences in the larger Heloderma species paralleing the change in venom biochemistry. In addition, as birds lack Factor XII, the ability to clot avian plasma suggested an additional procoagulant site of action, which was revealed to be the activation of Factor VII, with H. horridum being the most potent. This study also examined the effects upon the cardiovascular system, including the liberation of kinins from kininogen, which contributes to hypotension induction. This form of toxicity was previously described for Heloderma venoms, and was revealed in this study was to also be a pathophysiological effect of Lanthanotus and Varanus venoms. This suggests that this toxic activity was present in the venom of the last common ancestor of the anguimorph lizards, which is consistent with kallikrein enzymes being a shared toxin trait. This study therefore uncovered novel actions of anguimorph lizard venoms, not only contributing to the evolutionary biology body of knowledge but also revealing novel activities to mine for drug design lead compounds.