Cardiovascular research
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Cardiovascular research · Jan 2002
Randomized Controlled Trial Comparative Study Clinical TrialThe effect of preconditioning (ischemic and pharmacological) on myocardial necrosis following coronary artery bypass graft surgery.
Ischemic preconditioning is known to protect the human heart from ischemic injury during coronary artery bypass graft (CABG) surgery but is not practised routinely. Adenosine A1 receptor agonists may confer protection in this setting by mimicking preconditioning. The aim of this study was to compare preconditioning, by ischemia or an adenosine A1 receptor agonist (GR79236X), with an established method of myocardial protection in CABG, namely intermittent cross-clamp fibrillation. ⋯ Ischemic preconditioning is superior to the other techniques at limiting myocardial necrosis during CABG. Pharmacological preconditioning may confer some benefit but this was not statistically shown using a specific adenosine A1 agonist (GR79236X).
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Cardiovascular research · Nov 2001
Randomized Controlled Trial Clinical TrialShort-term effects of transdermal nicotine on acute tissue plasminogen activator release in vivo in man.
Cigarette smoking impairs peripheral endothelium-dependent vasodilatation and acute tissue plasminogen activator (t-PA) release in man. The aim of the study was to determine if this endothelial dysfunction is, in part, mediated by the effects of nicotine. ⋯ Short-term transdermal nicotine treatment does not affect endothelium-dependent vasomotion but does increase substance-P-induced t-PA release in vivo in man. This suggests that nicotine administration alters specific aspects of endothelial function and enhances the acute endogenous fibrinolytic capacity in vivo. The long-term effects of nicotine exposure, including the potential to cause depletion of endothelial t-PA stores, now needs to be assessed.
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Cardiovascular research · Jan 1997
Randomized Controlled Trial Clinical TrialHaemodynamic and endocrine effects of type 1 angiotensin II receptor blockade in patients with hypoxaemic cor pulmonale.
Angiotensin II (ANG II) is known to be a potent vasoconstrictor agent in the pulmonary circulation. Furthermore, type 1 ANG II receptor blockade with losartan attenuates acute hypoxic pulmonary vasoconstriction in normal subjects. The aim of this study was therefore to evaluate the haemodynamic and endocrine sequelae of type 1 ANG II receptor blockade in patients with hypoxaemic cor pulmonale. ⋯ Thus, selective type 1 ANG II receptor blockade appears to have beneficial pulmonary and endocrine effects, suggesting a possible therapeutic role in the management of hypoxaemic cor pulmonale.
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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 · Nov 1994
Randomized Controlled Trial Comparative Study Clinical TrialDofetilide reduces the incidence of ventricular fibrillation during acute myocardial ischaemia. A randomised study in pigs.
The aim was to investigate whether dofetilide, a new selective cardiac potassium channel blocker, would reduce the incidence of ischaemia induced ventricular fibrillation in closed chest pigs. ⋯ Dofetilide significantly reduces the incidence of ischaemia induced ventricular fibrillation in closed chest pigs.