Cardiovascular research
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Cardiovascular research · Jan 1997
Comparative StudyCardiopulmonary bypass tubes and prime solutions stimulate neutrophil adhesion molecules.
To evaluate effects of the material of the cardiopulmonary bypass (CPB) tubes (polyvinyl chloride, PVC) and prime solutions on expression of neutrophil adhesion molecule CD11b and L-selectin. ⋯ Mixing blood with acidic prime solution and/or exposing it to PVC tubes causes up-regulation of neutrophil adhesion molecule CD11b and down-regulation of L-selectin. Neutralisation of the prime solution reduces the extent of neutrophil activation, whereas haemodilution has no effect. Increasing plasma water is stimulating to the neutrophil. Modulation of prime solutions and the material of CPB tubes may reduce neutrophil activation which may reduce patient morbidity.
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Cardiovascular research · Sep 1996
Inhibition of beta- but not alpha 1-mediated adrenergic responses in isolated hearts and cardiomyocytes by nitric oxide and 8-bromo cyclic GMP.
The study was carried out to assess the effect of nitric oxide (NO) generation or inhibition of NO synthase on the cardiac response to beta- and alpha 1-adrenergic agonists. In addition, we determined the effects of the cell-permable analogue of cGMP, 8-bromo-cGMP (8Br-cGMP). ⋯ The present study demonstrate that NO as well as guanylate cyclase inhibitors and, to a lesser extent, 8Br-cGMP attenuate beta-receptor-mediated cardiac responses and supports the concept that NO serves as an endogenous regulator of beta-mediated effects of catecholamines in the heart. In addition, our findings suggest that the antiadrenergic effects of NO are restricted to these receptors but likely do not involve alpha 1-mediated effects.
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Cardiovascular research · Jul 1996
Electrical alternans and the onset of rate-induced pulsus alternans during acute regional ischaemia in the anaesthetised pig heart.
Electrical alternans and mechanical alternans are both associated with cardiac ischaemia and in the case of electrical alternans there is a strong link with serious ventricular arrhythmia. We elected to investigate the relationship between electrical and mechanical alternans in control and acutely ischaemic myocardium in the intact porcine heart to determine the nature of their interaction and in particular to determine if abnormal mechanical events play a role in arhythmogenesis as has been suggested in non-ischaemic preparations. ⋯ Pulsus alternans during acute ischaemia is associated with electrical alternans that can be out of phase in control and ischaemic areas. This could increase electrical dispersion which may be pro-arrhythmic.
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Cardiovascular research · Apr 1996
Randomized Controlled Trial Comparative Study Clinical TrialUltrafiltration after cardiopulmonary bypass in children: effects on hemodynamics, cytokines and complement.
The purpose of the study was to evaluate the clinical and hemodynamic effect of intraoperative extracorporeal ultrafiltration (UF) and its potential in reducing the plasma concentration of circulating cytokines and complement activation products following open heart surgery in children. ⋯ In this study no clinical or hemodynamic effect was registered after UF. TNF and C3a were occasionally detected in the ultrafiltrate but we were unable to demonstrate reduction of these or any of the other markers tested in the group subjected to ultrafiltration.
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Cardiovascular research · Feb 1996
Comparative StudyRight and left ventricular geometry and myocyte contractile processes with dilated cardiomyopathy: myocyte growth and beta-adrenergic responsiveness.
Comparison of the effects of supraventricular tachycardia-induced dilated cardiomyopathy on left and right ventricular isolated myocyte geometry and function. ⋯ This study demonstrated differences in left and right ventricular myocyte growth with supraventricular tachycardia-induced dilated cardiomyopathy and this differential growth response was associated with changes in contractile performance. Thus, in this model of cardiomyopathic disease, left and right ventricular growth and changes in contractile performance are not a homogenous process.