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Von Willebrand factor (VWF) is an emerging risk factor in acute coronary syndromes. Platelet Function Analyzer (PFA-100) with Collagen/Epinephrine (CEPI) is sensitive to functional alterations of VWF and also identifies patients with high on-treatment platelet reactivity (HPR). The objective of this study was to verify the effect of double dose (DD) of aspirin and clopidogrel on HPR detected by PFA-100 and its relation to VWF and to its regulatory metalloprotease ADAMTS-13. Between 2009 and 2011 we enrolled 116 consecutive patients with ST elevation myocardial infarction undergoing primary PCI with HPR at day 5 after PCI. Patients recruited were then randomized between a standard dose (SD,n=58) or DD of aspirin and clopidogrel (DD,n=58), maintained for 6 months follow-up. Blood samples for PFA-100, light transmittance aggregometry, and VWF/ADAMTS-13 analysis were collected after 5, 30, and 180 days (Times 0, 1, and 2). At Times 1 and 2 we observed a significantly higher CEPI closure times (CT) in DD as compared to SD (P<0.001). Delta of CEPI-CT(T1-T0)was significantly related to VWF (P<0.001) and inversely related to ADAMTS-13 (0.01). Responders had a significantly higher level of VWF atT0. Finally, in a multivariate model analysis, VWF and ADAMTS-13 in resulted significant predictors of CEPI-CT response (P=0.02). HRP detected by PFA-100 in acute myocardial infarction is reversible by DD of aspirin and clopidogrel; the response is predicted by basal levels of VWF and ADAMTS-13. PFA-100 may be a useful tool to risk stratification in acute coronary syndromes given its sensitivity to VWF.

Background: Neutrophil-granulocyte and mononuclear-cell functional changes occur during cardiopulmonary bypass and cardiovascular surgery. In particular, leukocyte–platelet interaction, leading to generation of heterotypic coaggregates, represents an amplification mechanism of the local inflammatory response and tissue damage. Methods: Samples of 20 patients were drawn from venous coronary sinus before cardioplegic arrest and immediately after reperfusion, as well as from peripheral blood at 5 and 24 h postoperatively. The granulocyte and monocyte surface expression of CD162, CD15s, CD18, and CD11b were quantified by flow cytometry at the different times. Parallel variations of circulating leukocyte–platelet conjugates (percentages) and a derived (cell number-normalized) leukocyte–platelet adhesion index were measured using a combination of antibodies against CD45, CD14, and CD41a. The evaluation of platelet functional state was carried out using antibodies against CD62P (P-selectin) and PAC-1. Results: Monocyte and granulocyte cell number increased markedly in coronary blood at reperfusion and in peripheral blood postoperatively when compared with measurements done before cardioplegia. A very different course characterized the changes of the leukocyte–platelet adhesion index with respect to the variations of circulating leukocyte–platelet coaggregates (percentages). Leukocyte molecules expression showed no significant variations for CD15s on both the leukocyte subsets, while a significant up-modulation for CD162 was observed on monocytes at 24 h after extracorporeal circulation (P = 0.0002), and for CD11b on granulocytes at 5 h postoperatively (P = 0.033). A loss of CD162 expression was observed in coronary blood at reperfusion (P = 0.0038) on granulocytes, associated to a down-modulation of CD18 (P = 0.0033) and CD11b (P = 0.0184) in peripheral blood at 24 h postoperatively. No significant up-regulation of platelet activatory molecules expression was found at coronary reperfusion, as well as postoperatively in the peripheral blood, when compared with the before-cardioplegia derived data. Conclusions: The over time variations of a normalized leukocyte–platelet adhesion index seem to reflect the cumulative leukocyte–platelet functional interaction more accurately than the parallel measurements of cellular conjugates. The absence of platelet activation suggests that the leukocyte membrane modifications play a main role in controlling the formation and stability of heterotypic leukocyte–platelet coaggregates after cardiac surgery with extracorporeal circulation. © 2006 International Society for Analytical Cytology

In animal models of conotruncal heart defects, an abnormal calcium sensitivity of the contractile apparatus and a depressed L-type calcium current have been described. Sarcoplasmic reticulum (SR) Ca(2+) ATPase (SERCA) is a membrane protein that catalyzes the ATP-dependent transport of Ca(2+) from the cytosol to the SR. The activity of SERCA is inhibited by phospholamban (PLN) and sarcolipin (SLN), and all these proteins participate in maintaining the normal intracellular calcium handling. Ryanodine receptors (RyRs) are the major SR calcium-release channels required for excitation-contraction coupling in skeletal and cardiac muscle. Our objective was to evaluate SERCA2a (i.e., the SERCA cardiac isoform), PLN, SLN, and RyR2 (i.e., the RyR isoform enriched in the heart) gene expression in myocardial tissue of patients affected by tetralogy of Fallot (TOF), a conotruncal heart defect. The gene expression of target genes was assessed semiquantitatively by RT-PCR using the calsequestrin (CASQ, a housekeeping gene) RNA as internal standard in the atrial myocardium of 23 pediatric patients undergoing surgical correction of TOF, in 10 age-matched patients with ventricular septal defect (VSD) and in 13 age-matched children with atrial septal defect (ASD). We observed a significantly lower expression of PLN and SLN in TOF patients, while there was no difference between the expression of SERCA2a and RyR2 in TOF and VSD. These data suggest a complex mechanism aimed to enhance the intracellular Ca(2+) reserve in children affected by tetralogy of Fallot.

Background Neutrophil and mononuclear cell functional changes represent a hallmark of inflammation during cardiopulmonary bypass and cardiovascular surgery. Knowledge of mechanisms underlying monocyte functional modulation in coronary blood may be useful to develop protective interventions that can limit ischemia/reperfusion injury. Methods Samples of 13 patients were drawn from venous coronary sinus before cardioplegic arrest and after reperfusion. The following parameters were studied: surface molecules expression (CD18, CD11b, CD44, CD162, CD15s, CD80, CD86, CD16, CD49d, CD29, CD25, HLA-DR, Toll-like receptor-4 [TLR-4], CXCR1, CCR2, CCR5, CX3CR1), oxidative burst response, monocyte-platelet conjugates (using antibodies against CD45, CD14, CD41a), and platelet activation (CD62P, PAC-1). Enzyme-linked immunosorbent assays were performed to measure levels of interleukin (IL)-1β, IL-6, IL-8, IL-10, and tumor necrosis factor-α (TNF-α). Results Coronary reperfusion down-modulated monocyte molecules expression, especially for CD18 (P = 0.048), CD44 (P = 0.0035), CD49d (P = 0.0029), CD29 (P = 0.032), HLA-DR (P < 0.0001), TLR-4 (P = 0.0109), CCR2 (P = 0.0184), CCR5 (P = 0.0396), and CX3CR1 (P < 0.0001). A marginal increase (P = 0.062) of a normalized adhesion index between monocytes and platelets was observed at reperfusion. No variations were detected for the monocyte oxidative burst and platelet activation. Increased levels of IL-6 (P = 0.013), TNF-α (P = 0.0272), and IL-10 (P = 0.0008) were measured after cardioplegia. Conclusions The lack of CD11b and CD25 variations and of the oxidative burst exclude monocyte activation at reperfusion. The high after-cardioplegia level of IL-10, the decreased expression of HLA-DR and TLR-4, and the absence of IL-1β and IL-8 suggest an IL-10–mediated functional depression of monocyte, including their adhesive and migratory capacities. The lack of an after-cardioplegia orientation toward IL-10 producing a “macrophage-like” CD14+/CD16+ phenotype might mean that myocardial infiltrating lymphocytes are the main source of IL-10. Moreover, the increased after-cardioplegia levels of IL-6 and TNF-α might be due to myocardial and endothelial activations. The increased adhesion index between monocyte and platelets, without receptor variations, suggests a monocyte membrane modification induced by extracorporeal circulation. © 2005 Wiley-Liss, Inc.

The non-thyroidal illness syndrome (NTIS) is considered a transient and completely reversible phenomenon, but it has been shown that it may last for several days postoperatively after coronary artery bypass grafting (CABG) surgery. This study was undertaken to assess thyroid function 6 months after uncomplicated CABG. The thyroid profile was evaluated in 40 consecutive patients undergoing CABG preoperatively, at 0, 12, 48, and 120 h postoperatively, and at 6-month follow-up. Triiodothyronine (T3), free T3 (FT3), free thyroxine (FT4) and thyroid stimulating hormone (TSH) were assayed using a microparticle enzyme immunoassay. T4 and total serum thyroid hormone-binding capacity (T-uptake) were measured on the same samples using a fluorescence polarization immunoassay. Patients with severe systemic illness and patients treated with amiodarone were excluded. All patients were euthyroid at admission. Mean age was 67.4+/-9.0 years. There were 31 (77.5%) men. Typical NTIS was observed in all patients, and the FT3 concentration was still reduced by postoperative day 5 (p

Background Cardiovascular surgery with cardiopulmonary bypass (CPB) induces systemic inflammation and postoperative complications depending on pro- and anti-inflammatory mechanisms. Activated polymorphonuclear cells and monocytes may be responsible for morbidity associated with CPB. Knowledge of the monocyte functional state in particular may help to develop protective interventions. Methods Samples were drawn from venous peripheral blood (basal condition, at 4 and 24 h after CPB) and coronary blood (before and after cardioplegic arrest) of 14 patients undergoing cardiac surgery. The following phenotypic and functional parameters of the monocyte population were studied by flow cytometry: surface molecules expression (CD18, CD11a, CD11b, CD14, CD15, CD45, HLA-DR, and Toll-like receptor [TLR]-4), myeloperoxidase (MPO) content, and intracellular cytokine production (tumor necrosis factor [TNF]-α, interleukin [IL]-1β, IL-6, and IL-8). Results Cardiac surgery with CPB induced down-modulation of surface molecules expression on peripheral monocytes, especially at 24 h after CPB, for CD18, CD11a, and CD11b (P < 0.003) and for the CD15 adhesive cluster (P = 0.0028) and HLA-DR (P < 0.001). At 4 h after CPB, downregulation was observed for CD14 (P = 0.004), CD45 (P = 0.014), and CD15 (P = 0.0056). A loss of MPO was detected in venous peripheral (at 24 h after CPB, P = 0.01) or coronary (at reperfusion, P < 0.02) blood. The CD15 cluster complex exhibited a down-modulation in coronary blood (at reperfusion, P = 0.0003). Spontaneous intracellular production of IL-1β, IL-6, and IL-8 decreased at 24 h after CPB (P < 0.05). Conclusions The down-modulation of integrins and adhesive receptor expression and the loss of MPO suggest a strong activation and shedding reaction of circulating monocyte after CPB, further exacerbated by contact with coronary ischemic vessels. The changes of differentiation antigens may reflect the appearance of a partially immature population immediately after CPB. The reduced proinflammatory cytokine production, observed at 24 h after CPB, suggests a functional polarization of circulating monocytes. © 2003 Wiley-Liss, Inc.