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Background: Hepcidin-25 is a potential marker for iron disorders with a demand for accessible assays. This study aimed to evaluate a commercial competitive enzyme-linked immunosorbent assay (cELISA) for hepcidin quantitation., Methods: Serum samples; 95 healthy subjects (HS), six patients with iron deficiency (ID), 84 patients with liver disorders (LD) and 220 hemodialysis patients (HD), were analyzed. Controls were used for imprecision, while accuracy was evaluated by quantitating hepcidin-25 with LC-MS/MS in 149 samples. Cross-reactivity for hepcidin-20 and hepcidin-22 was tested. Hepcidin-mRNA expression in 37 liver biopsies was measured., Results: S-hepcidin ranged from 8-76 and 2-31 μg/L in healthy men and women. Levels in ID, LD and HD significantly differed from HS. Total coefficients of variation (CV) for controls were 24% and 22%. Within-sample CV was 10%. Despite a good correlation with LC-MS/MS (r = 0.89), the cELISA showed higher values and detected hepcidin-20 and hepcidin-22. Hepcidin-mRNA correlated well with S-hepcidin using cELISA and LC-MS/MS (r = 0.69 and 0.64)., Conclusions: The correlation with LC-MS/MS is good and the examined kit can differentiate between patient groups although it is not specific for hepcidin-25. Considering ELISA's capacity to readily be set up, the investigated kit can be applied. Specific reference ranges are required.

Objectives: Ticagrelor reduces thrombotic events compared with clopidogrel in patients with acute coronary syndrome, but may also increase bleeding complications. Coronary artery bypass grafting (CABG)-related bleeding complications have not previously been compared in clopidogrel and ticagrelor-treated patients outside the controlled environment of clinical trials., Methods: Four hundred and five consecutive CABG patients with acute coronary syndrome were included in a prospective observational study. The patients were treated with aspirin and ticagrelor (n = 173) or aspirin and clopidogrel (n = 232). Ticagrelor/clopidogrel was discontinued 5 days before surgery whenever deemed possible. Major bleeding complications according to modified blood conservation using antifibrinolytics in a randomized trial criteria (postoperative blood loss >1500 ml/12 h, re-exploration, red blood cell transfusion >10 units or death because of bleeding) were compared in all patients and when ticagrelor/clopidogrel was discontinued ≥5 days (n = 280), 2-4 days (n = 40) or 0-1 day before surgery (n = 85)., Results: Major bleeding complications did not differ significantly between ticagrelor- and clopidogrel-treated patients when all patients were compared (14.5 vs 13.8%, P = 0.89). Likewise, there were no significant differences between ticagrelor and clopidogrel when either drug was discontinued ≥5 days before surgery (6.8 vs 9.9%, P = 0.40) or 2-4 days before surgery (6.3 vs 25.0%, P = 0.21). When ticagrelor/clopidogrel was discontinued 0-1 day before surgery, there was a strong trend towards higher incidence of major bleeding in ticagrelor-treated patients (41.0 vs 21.7%, P = 0.063)., Conclusions: There was no difference in major bleeding complications overall or when ticagrelor or clopidogrel was used in accordance with guidelines. In patients on dual antiplatelet medication up to 1 day before surgery, there tended to be more bleeding complications in ticagrelor-treated patients., (© The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Introduction: Bleeding after cardiac surgery may be caused by surgical factors, impaired haemostasis, or a combination of both. Transfusion of blood products is used to improve haemostasis, but little is known about what combination is optimal. We hypothesized that addition of both fibrinogen and platelets to blood samples from cardiac surgery patients would improve clot formation and platelet aggregation to a greater extent than if the components were added separately., Materials and Methods: Increasing doses of fibrinogen concentrate (+0.5, 1.0, and 1.5 g · l(-1)) and/or platelet concentrate (+46, 92, and 138 × 10(9) platelets l(-1)) were added to postoperative blood samples from 15 cardiac surgery patients. Clot formation was assessed with rotational thromboelastometry and platelet aggregation was assessed with multiple-electrode aggregometry before and after addition of the blood products. The effects of the different additives were compared., Results and Conclusions: Ex vivo supplementation with fibrinogen or platelet concentrate resulted in significantly shortened clotting time and improved clot strength in a dose-dependent manner. Combination of fibrinogen and platelets further improved the clotting time and strength. Platelet supplementation enhanced platelet aggregation in a dose-dependent manner while fibrinogen had no or reducing effect. Combining fibrinogen and platelets improved platelet aggregation less than the use of platelets alone. In conclusion, combined platelet and fibrinogen supplementation of blood samples from cardiac surgery patients had an additive effect on clot formation compared to the individual components, but it resulted in less platelet aggregation than with platelet supplementation alone. These results may have implications for clinical transfusion protocols., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Background: Transfusion of platelet concentrate is often used to treat bleeding in patients on platelet inhibitors, but little is known about its efficacy between different inhibitors. We assessed the effect of ex vivo platelet supplementation on platelet aggregability in blood samples from patients treated with acetylsalicylic acid (ASA), clopidogrel, or ticagrelor., Methods: Platelet aggregability was investigated with multiple electrode aggregometry with adenosine diphosphate (ADP), arachidonic acid (to assess ASA-dependent aggregability), and thrombin receptor activating peptide-6 (TRAP) as activators in whole-blood samples from patients treated with ASA (n=10), ASA+clopidogrel (n=15), or ASA+ticagrelor (n=15), and from healthy controls (n=10). Aggregability was measured before and after supplementation of AB0-compatible fresh apheresis platelets (+46, +92, and +138×10(9) litre(-1))., Results: Both ASA-dependent and ADP-dependent aggregability improved in a dose-dependent fashion after platelet supplementation. ASA-dependent aggregability was completely restored in all patient groups, but there was only a small improvement in ADP-dependent aggregability in patients on dual antiplatelet therapy. There was less effect of platelet supplementation on ADP- and ASA-dependent aggregability in ticagrelor-treated patients than in clopidogrel-treated patients [3.9 (95% confidence interval 1.6-6.3) vs 9.0 (5.2-12.8) AU×min (P=0.021) and 48 (36-59) vs 69 (60-78) AU×min (P=0.004), respectively, at the highest platelet dose]., Conclusions: Platelet supplementation improved platelet aggregability independently of antiplatelet therapy. The effect on ADP-dependent platelet inhibition was limited however. Reduced effect of platelet transfusion is more likely within 2 h of drug intake in patients treated with ASA+ticagrelor compared with ASA+clopidogrel.

Objective: To assess the prevalence, indications and appropriateness of antiplatelet therapy in patients operated for acute aortic dissection and its associations with bleeding complications and mortality., Design: A retrospective single-centre study comparing patients with and without ongoing antiplatelet therapy., Setting: University Hospital in Western Sweden., Patients: 133 consecutive patients operated during 2007-2011., Interventions: All patients were operated for acute aortic dissection type A., Main Outcome Measures: Indication and appropriateness of antiplatelet therapy; perioperative bleeding complications, transfusions and mortality., Results: 43 of 133 patients (32%) had ongoing platelet inhibition at the time of surgery, 19 (14%) with acetylsalicylic acid (ASA) alone and 24 (18%) with ASA and clopidogrel. Unspecific chest pain and ST depression were the most common indications (42% and 23%, respectively). 2.3% had ST elevation and 12% had elevated biomarkers for myocardial injury. Only 29% of the patients with dual antiplatelet therapy had appropriate treatment according to current guidelines. Patients with ongoing platelet inhibition had significantly larger intraoperative (1800 (IQR 950-4250) vs 800 ml (500-2500), p=0.010) and postoperative bleeding volumes (800 (420-1605) vs 500 ml (390-1070), p=0.037). 30-day mortality in patients on dual antiplatelet therapy was 30.4% compared with 13.0% in patients with no or single antiplatelet therapy (p=0.038)., Conclusions: The indication for immediate antiplatelet therapy in patients later operated for acute aortic dissection was weak or absent in the majority of cases. Patients with ongoing platelet inhibition had more bleeding complications. Dual antiplatelet therapy was associated with increased early mortality.