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Coagulopathic bleeding during and after cardiac surgery is associated with increased morbidity and mortality. Viscoelastic testing is increasingly used instead of laboratory testing. Our aim was to compare a new viscoelastic point-of-care device, the Quantra® System, with thromboelastography and standard laboratory testing. After ethical approval and with written informed consent, we prospectively recruited adult patients undergoing urgent cardiac surgery at increased risk of bleeding. Clot time and clot stiffness values were compared before, during and after cardiopulmonary bypass. We prospectively recruited 52 patients, of whom 34 (65%) were transfused with red blood cells. Our usual transfusion thresholds for fibrinogen (1.5 g.l-1 ), platelets (100,000.μl-1 ), prothrombin time (20 s), activated partial thromboplastin time (48 s) and maximum amplitude on thromboelastography (50 mm) corresponded to Quantra values of fibrinogen clot stiffness 2.0 hPa, platelet clot stiffness 13.5 hPa, clot time 159 s, clot time 183 s and clot stiffness 17.0 hPa, respectively. These Quantra thresholds showed high negative predictive value for low platelets (platelet clot stiffness, 97.4%), prolonged activated partial thromboplastin time (clot time, 92.6%) and reduced maximum amplitude on thromboelastography (clot stiffness, 93.6%). The Quantra predicted clinical need for transfusion of platelets (area under the curve 0.71, p = 0.001) but all tests performed poorly at predicting the need for fresh frozen plasma transfusion. We have shown that point-of-care testing using the novel Quantra system provides useful data for guiding transfusion management. [ABSTRACT FROM AUTHOR]

Cardiac surgery and cardiopulmonary bypass are associated with haemodilution, activation of haemostasis and blood transfusion. We undertook a randomised controlled trial that included 53 patients in order to compare autotransfusion of residual cardiopulmonary bypass blood with residual blood concentrated using the novel Hemosep® device. There was no difference in patients' mean ( SD) haemoglobin concentration after autotransfusion of unprocessed blood compared with Hemosep; 103.5 (10.2) g.l−1 vs 106.2 (12.4) g.l−1, respectively, p = 0.40. The mean ( SD) change in haemoglobin concentration after autotransfusion was 5.9 (5.3) g.l−1 in the control group compared with 4.9 (6.3) g.l−1 in the Hemosep group, p = 0.545. Adjusted for baseline haemoglobin concentrations, the estimated mean (95% CI) difference in change in haemoglobin concentration (control vs Hemosep) was 0.57 (−2.65 to 3.79) g.l−1, p = 0.72. This was despite Hemosep's reducing the weight of the blood from a mean ( SD) of 778.7 (243.0) g to 607.3 (248.2) g, p < 0.001. The haemoglobin concentration in the processed blood increased from a mean ( SD) of 87.0 (15.1) g.l−1 to 103.7 (17.4) g.l−1, p < 0.001. We conclude that Hemosep is capable of haemoconcentration when employed to process residual cardiopulmonary bypass blood, but that this is insufficient to increase patient haemoglobin. [ABSTRACT FROM AUTHOR]

Peptides participating in the hypothalamic control of feeding behaviour are also involved in the central autonomic control of gastrointestinal functions, such as secretion and motility. An anatomical interaction and functional relationship in the central nervous system between the feeding-related peptides neuropeptide Y and ghrelin is well documented. Furthermore, it has been shown that feeding-related peptides can influence digestive function via central corticotrophin-releasing factor (CRF) pathways. In the present study, we investigated the role of ghrelin in the central autonomic control of colonic motility. Furthermore, we addressed the hypothesis that ghrelin is involved in the hypothalamic control of colonic motor function, utilizing central neuropeptide Y receptors and hypothalamic CRF pathways. Ghrelin (0.03, 0.06 and 0.12 nmol) bilaterally microinjected into the paraventricular nucleus (PVN) induced a significant stimulation of colonic propulsion. In particular, the colonic transit time decreased from 312 ± 7 min to 198 ± 12 min. Microinjection of the neuropeptide Y1 receptor antagonist, BIBP-3226 (200 pmol), or the nonselective CRF receptor antagonist, astressin (30 pmol), into the PVN abolished the stimulatory effect of ghrelin injected into the PVN on colonic transit time, whereas pretreatment with the selective CRF2 receptor, antisauvagine-30 (28 pmol), failed to affect the effect of PVN-ghrelin injection on colonic propulsion. These results suggest that ghrelin can act as central modulator of gastrointestinal motor functions at the level of the PVN via neuropeptide Y1- and CRF1 receptor-dependent mechanisms. [ABSTRACT FROM AUTHOR]

Chronic thromboembolic pulmonary hypertension (CTEPH) results from an incomplete resolution of acute pulmonary embolism, leading to occlusive organized thrombi, vascular remodeling, and associated microvasculopathy with pulmonary hypertension (PH). A definitive CTEPH diagnosis requires PH confirmation by right-heart catheterization and evidence of chronic thromboembolic pulmonary disease on imaging studies. Surgical removal of the organized fibrotic material by pulmonary endarterectomy (PEA) under deep hypothermic circulatory arrest represents the treatment of choice. One-third of patients with CTEPH are not deemed suitable for surgical treatment, and medical therapy or interventional balloon pulmonary angioplasty presents alternative treatment options. Pulmonary endarterectomy in patients with technically operable disease significantly improves symptoms, functional capacity, hemodynamics, and quality of life. Perioperative mortality is <2.5% in expert centers where a CTEPH multidisciplinary team optimizes patient selection and ensures the best preoperative optimization according to individualized risk assessment. Despite adequate pulmonary artery clearance, patients might be prone to perioperative complications, such as right ventricular maladaptation, airway bleeding, or pulmonary reperfusion injury. These complications can be treated conventionally, but extracorporeal membrane oxygenation has been included in their management recently. Patients with residual PH post-PEA should be considered for medical or percutaneous interventional therapy., Competing Interests: Declaration of Competing Interest None., (Copyright © 2023. Published by Elsevier Inc.)

Modern four-factor prothrombin complex concentrate was designed originally for rapid targeted replacement of the coagulation factors II, VII, IX and X. Dosing strategies for the approved indication of vitamin K antagonist-related bleeding vary greatly. They include INR and bodyweight-related protocols as well as fixed dose regimens. Particularly in the massively bleeding trauma and cardiac surgery patient, four-factor prothrombin complex concentrate is used increasingly for haemostatic resuscitation. Members of the Transfusion and Haemostasis Subcommittee of the European Association of Cardiothoracic Anaesthesiology performed a systematic literature review on four-factor prothrombin complex concentrate. The available evidence has been summarised for dosing, efficacy, drug safety and monitoring strategies in different scenarios. Whereas there is evidence for the efficacy of four-factor prothrombin concentrate for a variety of bleeding scenarios, convincing safety data are clearly missing. In the massively bleeding patient with coagulopathy, our group recommends the administration of an initial bolus of 25 IU.kg -1 . This applies for: the acute reversal of vitamin K antagonist therapy; haemostatic resuscitation, particularly in trauma; and the reversal of direct oral anticoagulants when no specific antidote is available. In patients with a high risk for thromboembolic complications, e.g. cardiac surgery, the administration of an initial half-dose bolus (12.5 IU.kg -1 ) should be considered. A second bolus may be indicated if coagulopathy and microvascular bleeding persists and other reasons for bleeding are largely ruled out. Tissue-factor-activated, factor VII-dependent and heparin insensitive point-of-care tests may be used for peri-operative monitoring and guiding of prothrombin complex concentrate therapy., (© 2020 Association of Anaesthetists.)

Bivalirudin, a direct thrombin inhibitor with a fast onset of action and short half-life, is often referred to as an alternative anticoagulant to a heparin/protamine regimen. Bivalirudin demonstrated promising results as an anticoagulant in cardiac surgery with and without cardiopulmonary bypass, postcardiotomy extracorporeal membrane oxygenation, interventional cardiology and endovascular procedures, and particularly in the treatment of patients with heparin-induced thrombocytopenia undergoing high-risk cardiac surgery. Currently, bivalirudin in cardiac surgery with cardiopulmonary bypass has a limited clinical spectrum, likely because the still obvious advantages of its competitor, heparin, outweigh it in terms of medical costs, established point-of-care monitoring systems, and availability of protamine as a reversal agent. The unique pharmacology of the drug also requires adjustment of surgical and perfusion strategy. In contrast, in off-pump coronary artery surgery, established protocols from interventional cardiology can be easily translated into the operating room. In this setting bivalirudin has the potential for a more important role in the future. Through a triple mechanism of action-inhibition of plasma thrombin, clot bound thrombin, and collagen-induced platelet activation-bivalirudin may perform better than heparin by attenuating the immediate postoperative prothrombotic state and thus positively impacting the early coronary graft patency after off-pump coronary artery bypass grafting. Further studies are necessary to better evaluate this niche field and discover further applications for this unique anticoagulant., Competing Interests: Declaration of Competing Interest The authors have no conflicts of interest to disclose., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Coagulopathic bleeding during and after cardiac surgery is associated with increased morbidity and mortality. Viscoelastic testing is increasingly used instead of laboratory testing. Our aim was to compare a new viscoelastic point-of-care device, the Quantra ® System, with thromboelastography and standard laboratory testing. After ethical approval and with written informed consent, we prospectively recruited adult patients undergoing urgent cardiac surgery at increased risk of bleeding. Clot time and clot stiffness values were compared before, during and after cardiopulmonary bypass. We prospectively recruited 52 patients, of whom 34 (65%) were transfused with red blood cells. Our usual transfusion thresholds for fibrinogen (1.5 g.l -1 ), platelets (100,000.μl -1 ), prothrombin time (20 s), activated partial thromboplastin time (48 s) and maximum amplitude on thromboelastography (50 mm) corresponded to Quantra values of fibrinogen clot stiffness 2.0 hPa, platelet clot stiffness 13.5 hPa, clot time 159 s, clot time 183 s and clot stiffness 17.0 hPa, respectively. These Quantra thresholds showed high negative predictive value for low platelets (platelet clot stiffness, 97.4%), prolonged activated partial thromboplastin time (clot time, 92.6%) and reduced maximum amplitude on thromboelastography (clot stiffness, 93.6%). The Quantra predicted clinical need for transfusion of platelets (area under the curve 0.71, p = 0.001) but all tests performed poorly at predicting the need for fresh frozen plasma transfusion. We have shown that point-of-care testing using the novel Quantra system provides useful data for guiding transfusion management., (© 2019 Association of Anaesthetists.)

Background: Pulmonary endarterectomy (PEA) is a curative treatment option for more than 60% of patients with chronic thromboembolic pulmonary hypertension (CTEPH). For selected inoperable patients, interventional balloon pulmonary angioplasty (BPA) has recently been established in addition to medical treatment. This approach disrupts scar tissue occluding the pulmonary arteries, leading to an improvement in parenchymal perfusion. CTEPH is occasionally heterogeneous, with operable disease on one side but peripheral, inoperable changes on the contralateral side. Performing unilateral PEA (on the operable side only) in these patients may lead to a worse hemodynamic outcome and increased mortality compared with patients who that can be surgically corrected bilaterally. We sought to determine the feasibility, safety, and benefits of BPA applied to the contralateral lung in several patients with predominantly unilateral disease that was amenable to treatment by PEA., Methods: Standard unilateral PEA in deep hypothermic circulatory arrest was performed in 3 CTEPH patients with poor pulmonary hemodynamics, and inoperability of the contralateral pulmonary artery obstructions was confirmed. The inoperable side was treated by BPA. The intervention was performed during the rewarming phase of cardiopulmonary bypass., Results: A dramatic improvement in pulmonary hemodynamics, with a mean reduction in pulmonary vascular resistance of 842 dyne · sec/cm(5), was achieved in all patients. World Health Organization Functional Class was also significantly improved at the midterm follow-up., Conclusions: The combination of surgical PEA and interventional BPA is a new treatment option for highly selected high-risk CTEPH patients. A multidisciplinary CTEPH expert team is a basic pre-requisite for this complex concept., (Copyright © 2016 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.)

Objectives: The differential diagnosis between iron deficiency anaemia (IDA) and anaemia of chronic disease (ACD) with or without associated iron deficiency can be challenging. We assessed the use of different parameters, both classical like ferritin, transferrin saturation and stainable bone marrow iron stores, and novel markers such as low haemoglobin density (LHD) and hepcidin to help discriminate between the three entities. This would allow the detection of patients with ACD with associated iron deficiency, which could benefit from iron supplementation that would have otherwise remained undetected., Materials and Methods: Prospective and observational cohort study from 2012 to 2013 where 200 anaemic cardiac surgical patients were recruited and 165 were studied. Detailed blood and bone marrow analyses were performed to establish the aetiology of anaemia., Results: Seventy-four patients (44.8%) had ACD and 29 (39%) of these had an elevated LHD indicating concomitant iron deficiency. Hepcidin was inappropriately normal or increased in the IDA and ACD group. Mean hepcidin was however lower in the group with IDA (4.8 ng/mL) than in the ACD group (15.0 ng/mL; p=0.002). Median hepcidin was lower in patients with ACD and iron restriction as indicated by LHD >4% (17.5 ng/mL) than on those with no iron restriction (25.9 ng/mL; p=0.045). In patients with ACD there was no concordance between Perl's stain and LHD., Conclusions: LHD was superior to hepcidin and bone marrow iron stores in identifying patients with ACD and associated iron deficiency, which would potentially benefit from parenteral iron therapy., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Background: Administration of coagulation factor concentrates to treat bleeding after cardiac surgery with cardiopulmonary bypass might be a strategy for reducing allogeneic blood transfusions, particularly for patients treated with warfarin preoperatively. We performed an exploratory analysis on whether the use of prothrombin complex concentrate (PCC) is safe and effective compared with fresh frozen plasma (FFP) to treat coagulopathy after pulmonary endarterectomy surgery with deep hypothermic circulatory arrest., Methods: Consecutive adult patients who underwent pulmonary endarterectomy surgery between January 2010 and September 2012 and received PCC or FFP to treat coagulopathy were studied. Blood loss during the first 12 hours of admission to the intensive care unit and patient outcomes were compared with propensity score adjustment., Results: Three hundred fifty-one patients underwent pulmonary endarterectomy surgery, all of whom had warfarin discontinued for up to 5 days before surgery; bleeding complications requiring transfusion of blood products were observed in 108 (31%) patients. Of those, 55 received only FFP and 45 received only PCC, whereas 8 received both. Blood loss was significantly greater in the FFP group compared with the PCC group after 12 hours (median [interquartile range], 650 mL [325-1075] vs 277 mL [175-608], P = 0.008). However, there was no difference in the frequency of patients receiving a red blood cell transfusion (number [percent], 44 [80%] vs 34 [76%], P = 0.594) or in the number of units of red blood cells transfused (median [interquartile range], 2 [1-4] vs 3 [1-5] units, P = 0.181). The final propensity score included preoperative international normalized ratio, postoperative activated partial thromboplastin time, and postoperative platelet count. After inclusion of the propensity score in the regression analyses, there were no differences between patients receiving only PCC and patients receiving only FFP in the need for renal replacement therapy (odds ratio [OR] 2.39, 95% confidence interval [CI] 0.51-11.20, P = 0.27), 30-day-mortality (OR 0.32, 95% CI 0.03-3.36, P = 0.35), intracranial hemorrhage (OR 0.73, 95% CI 0.14-3.89, P = 0.71), hospital length of stay (hazard ratio 0.77, 95% CI 0.50-1.19, P = 0.24), or duration of intensive care stay (hazard ratio 0.91, 95% CI 0.59-1.40, P = 0.66)., Conclusions: This retrospective analysis suggests that PCC may be an alternative to FFP in patients previously treated with warfarin who are coagulopathic after major cardiac surgery. Randomized controlled studies powered to evaluate efficacy and important postoperative outcomes for patients receiving PCC versus FFP for coagulopathic bleeding after cardiopulmonary bypass are warranted.

Cardiac surgery and cardiopulmonary bypass are associated with haemodilution, activation of haemostasis and blood transfusion. We undertook a randomised controlled trial that included 53 patients in order to compare autotransfusion of residual cardiopulmonary bypass blood with residual blood concentrated using the novel Hemosep(®) device. There was no difference in patients' mean (SD) haemoglobin concentration after autotransfusion of unprocessed blood compared with Hemosep; 103.5 (10.2) g.l(-1) vs 106.2 (12.4) g.l(-1), respectively, p = 0.40. The mean (SD) change in haemoglobin concentration after autotransfusion was 5.9 (5.3) g.l(-1) in the control group compared with 4.9 (6.3) g.l(-1) in the Hemosep group, p = 0.545. Adjusted for baseline haemoglobin concentrations, the estimated mean (95% CI) difference in change in haemoglobin concentration (control vs Hemosep) was 0.57 (-2.65 to 3.79) g.l(-1), p = 0.72. This was despite Hemosep's reducing the weight of the blood from a mean (SD) of 778.7 (243.0) g to 607.3 (248.2) g, p < 0.001. The haemoglobin concentration in the processed blood increased from a mean (SD) of 87.0 (15.1) g.l(-1) to 103.7 (17.4) g.l(-1), p < 0.001. We conclude that Hemosep is capable of haemoconcentration when employed to process residual cardiopulmonary bypass blood, but that this is insufficient to increase patient haemoglobin., (© 2015 The Association of Anaesthetists of Great Britain and Ireland.)

Objectives: Preoperative anaemia is associated with increased morbidity and mortality. We sought to determine the relative frequencies of the different causes of anaemia including absolute and functional iron deficiency, and the association of different haematological parameters, including plasma hepcidin, a key protein responsible for iron regulation, with outcomes after cardiac surgery., Methods: Prospective observational study between January 2012 and 2013; 200 anaemic cardiac surgical patients were recruited and 165 were studied. Detailed blood and bone marrow analysis was performed. Primary outcome was days alive and out of hospital., Results: Mean (SD) haemoglobin (Hb) was 102 (8) g/L for women and 112 (11) g/L for men. Regarding outcomes, 137 (83%) patients were transfused at least one unit of red blood cells; 30-day mortality was 1.8% (three patients). Functional iron deficiency was diagnosed in 78 patients (47%). Plasma hepcidin concentration was the only haematological variable associated with outcome, with mean days alive and out of hospital 2.7 (95% CI 0.4 to 5.1) days less if hepcidin ≥20 ng/mL compared with <20 ng/mL (p=0.024). Multivariable analysis showed that the association between hepcidin and outcome was independent of risk (European System for Cardiac Operative Risk Evaluation), transfusion and Hb., Conclusions: Functional iron deficiency was the most common cause of anaemia but was not associated with outcome. The only haematological parameter that was associated with outcome was hepcidin concentration, which is a novel finding and introduces further complexity into our understanding of the role of iron and its regulation by hepcidin. We propose that future research should target patients with elevated hepcidin., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Background: Coagulopathy is common after cardiopulmonary bypass (CPB), and platelet dysfunction is frequently considered to be a major contributor to excessive bleeding. Exposure to hypothermia may exacerbate the platelet function defect. We assessed platelet function during and after deep hypothermia with multiple electrode aggregometry (Multiplate(®); Verum Diagnostica GmbH, Munich, Germany)., Methods: Twenty adult patients undergoing pulmonary endarterectomy for chronic pulmonary hypertension were cooled on CPB to 20°C and deep hypothermic arrest was used to facilitate surgery. We analyzed platelet aggregation in whole blood samples at 12 measuring points during and after the procedure. Platelet aggregation was stimulated via the thrombin receptor (TRAPtest) at the patient's actual body temperature (AUC-CT) and after rewarming the samples to 37°C (AUC-37). In addition, we tested samples at 2 time points after 2 minutes of in vitro incubation with 20 μg protamine (0.067 μg/μL). Results are expressed as area under the aggregation curve (AUC)., Results: Cooling resulted in a marked decrease of platelet aggregation to a minimum AUC-CT of 20.5 (95% confidence interval [CI] 8.9-32.1) at 20°C body temperature. AUC-CT was significantly different from baseline (92.8, 95% CI 82.5-103.1) for temperatures of ≤28°C (P < 0.001), whereas the change in AUC-37 only became significant at the lowest body temperature (59.4, 95% CI 41.3-77.4). After rewarming to 36°C, AUC-CT and AUC-37 had recovered to 67.6 (95% CI 53.9-81.3) and 71.7 (95% CI 52.5-90.8), respectively. The mean AUC-CT was significantly lower than the mean AUC-37 from cooling at 28°C to warming at 24°C inclusive, and the relationship with temperature during cooling was significantly different between AUC-CT and AUC-37 (regression coefficients 4.7 [95% CI 4.2-5.2] vs 1.3 [95% CI 0.7-1.9]; P < 0.0001). After administration of protamine, mean aggregation decreased significantly for both measurements by 38.2 (95% CI -27.9 to -48.5; P < 0.001) and 44.5 (95% CI -58.5 to -30.5; P < 0.001), respectively. Similarly, adding protamine in vitro resulted in a decrease of mean aggregation by 35.1 (95% CI -71.0 to 0.8; P = 0.055) when measured after administration of heparin, and 56.5 (95% CI -94.5 to -18.5; P = 0.005) at the end of CPB., Conclusion: Platelet aggregation, assessed by multiple electrode aggregometry (Multiplate), was severely affected during deep, whole-body hypothermia. This effect was partially reversible after rewarming, and was distinct from a general decline of platelet aggregation during CPB. Protamine also caused a significant decrease in platelet aggregation in vivo and in vitro.

The complex formation of malvidin-3-O-glucoside with several polyphenols, the so-called "copigmentation" phenomenon, was studied in aqueous solutions. To simulate the copigmentation process during fermentation, the stability of the formed complexes was examined in dependence of the ethanol content of the aqueous solution. Results indicate that stronger and larger complexes are formed, when the ethanol content exceeds a critical margin of 8vol.% However, the size of complexes of malvidin/procyanidin and malvidin/epicatechin is drastically reduced above this critical concentration. Fluorescence lifetime and solvent relaxation measurements give insight into the particular processes at molecular level and will help us comprehend the first important steps during winemaking in order to recommend an optimized winemaking technology to ensure extraordinary colour stability in red wines.

The interaction of malvidin-3-O-glucoside with ellagic acid was studied in aqueous solutions in dependence of the ethanol content of the samples. The results show significant changes of the thermodynamic parameters when the ethanol content exceeds 8%vol. The quantum chemical calculations and the solvent relaxation measurements validate that the solvatation shell of the malvidin-ellagic acid complexes changes from water to ethanol around this critical alcoholic concentration. The change of the solvate shell is accompanied by increasing copigmentation; i.e., higher "multi-sandwich" complexes are formed. According to the considerable role of this interaction (namely copigmentation) in the formation of color in red wines, our results have several consequences for the winemaking process with regard to the stabilization of wine color.

In order to identify novel protein kinases, which are involved in signal transduction processes after exposure of cells to ionizing radiation we screened HL-60 cells using an in-gel renaturation assay. Using this approach we identified a renaturable serine/threonine kinase with an apparent molecular mass of 90 kDa (pK90). The activity of pK90 dropped within minutes after exposure to a dose of 10 Gy. It reached a minimum 15-30 min after irradiation and increased back to pre-treatment values 6h later. A down-regulation of the kinase activity was detectable after a dose of 1 Gy. Failure of H(2)O(2) to down-regulate pK90 activity indicates a requirement for DNA double-strand-breaks to modulate the kinase activity. In contrast to the molecular mass of 90 kDa in SDS-PAGE we found a molecular mass of around 450 kDa for the native protein using gel filtration chromatography, indicating that pK90 forms a multi-protein complex under native conditions. To identify pK90 we partially purified the protein by three affinity chromatography steps (heparin-Sepharose, phosphate metal affinity, and Cibacron-Blue-F3G-A-Sepharose). Mass spectrometric analysis of the purified 90 kDa fraction showed that pK90 is identical to Tlk1, which was verified by immunoprecipitation.

Basiliximab, a high-affinity chimeric monoclonal antibody, is effective in reducing acute rejection episodes in renal allograft recipients. We assessed the ability of this antibody to similarly improve the outcome in liver transplant recipients. Adult recipients of a primary cadaveric liver transplant were randomized to treatment, stratified by hepatitis C virus (HCV) seropositivity. Patients were administered 40 mg of basiliximab (n = 188) or placebo (n = 193) as two 20-mg bolus injections days 0 and 4, plus cyclosporine and steroids. Primary efficacy variables were biopsy-confirmed acute rejection and its composite end point, including death or graft loss, and were assessed at 6 and 12 months and by HCV cohort. Because of differential efficacy responses between HCV-positive and HCV-negative cohorts, an additional analysis incorporating HCV recurrence as a component of treatment failure, termed problem-free transplant, was introduced. Safety and tolerability were monitored over the 12 months of the study. All 381 patients were assessable, and no meaningful differences in background characteristics were apparent between treatment groups. Biopsy-confirmed acute rejection rates 6 months after transplantation were 35.1% in the basiliximab group versus 43.5% in the placebo group. For death, graft loss, or first biopsy-confirmed acute rejection, rates were 44.1% versus 52.8%, respectively. The reduction in rejection episodes was concentrated in the HCV-negative cohort (14.5% relative to placebo; P =.034), with a much smaller difference (2.9%) in the HCV-positive cohort. For HCV-positive patients, problem-free transplant was shown at 12 months in 26.6% of the basiliximab group versus 11.6% in the placebo group (P =.020) and for all patients at 12 months in 39.7% of the basiliximab group versus 30.1% in the placebo group (P =.035). The incidence of infection and other adverse events was similar across the two treatment groups. There were 56 deaths (25 deaths, basiliximab group; 31 deaths, placebo group) over the 12-month study. The intravenous bolus injection was well tolerated. Immunoprophylaxis with 40 mg of basiliximab, in combination with cyclosporine and steroids, reduces the incidence of acute rejection episodes with no clinically relevant safety or tolerability concerns. The influence of HCV recurrence on efficacy results can be accounted for in future trials by using the concept of problem-free transplant, incorporating recurrence as a component of treatment failure.

Background and Purpose: Radioactive stents are under investigation for reduction of coronary restenosis. However, the actual dose delivered to specific parts of the coronary artery wall based on the individual vessel anatomy has not been determined so far. Dose-volume histograms (DVHs) permit an estimation of the actual dose absorbed by the target volume. We present a method to calculate DVHs based on intravascular ultrasound (IVUS) measurements to determine the dose distribution within the vessel wall., Materials and Methods: Ten patients were studied by intravascular ultrasound after radioactive stenting (BX Stent, P-32, 15-mm length) to obtain tomographic cross-sections of the treated segments. We developed a computer algorithm using the actual dose distribution of the stent to calculate differential and cumulative DVHs. The minimal target dose, the mean target dose, the minimal doses delivered to 10 and 90% of the adventitia (DV10, DV90), and the percentage of volume receiving a reference dose at 0.5 mm from the stent surface cumulated over 28 days were derived from the DVH plots. Results were expressed as mean+/-SD., Results: The mean activity of the stents was 438+/-140 kBq at implantation. The mean reference dose was 111+/-35 Gy, whereas the calculated mean target dose within the adventitia along the stent was 68+/-20 Gy. On average, DV90 and DV10 were 33+/-9 Gy and 117+/-41 Gy, respectively. Expanding the target volume to include 2.5-mm-long segments at the proximal and distal ends of the stent, the calculated mean target dose decreased to 55+/-17 Gy, and DV 90 and DV 10 were 6.4+/-2.4 Gy and 107+/-36 Gy, respectively., Conclusions: The assessment of DVHs seems in principle to be a valuable tool for both prospective and retrospective analysis of dose-distribution of radioactive stents. It may provide the basis to adapt treatment planning in coronary brachytherapy to the common standards of radiotherapy.