Cardiovascular research
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Cardiovascular research · Jan 1994
Randomized Controlled Trial Comparative Study Clinical TrialEffects of a nitric oxide synthase inhibitor in humans with septic shock.
Studies in animals have indicated that increased production of nitric oxide from an inducible isoform of nitric oxide synthase contributes to the pathophysiology of endotoxic and cytokine induced shock. The aim of this study was to determine the role of nitric oxide in septic shock in humans. ⋯ Low doses of L-NMMA cause a widespread increase in vascular tone and raise blood pressure in patients with septic shock. Overproduction of nitric oxide appears to be an important mechanism in septic shock in patients, and inhibition of nitric oxide synthesis might provide a novel therapeutic approach to this condition. However, L-NMMA produced a fall in cardiac output and it is possible that this would worsen tissue perfusion. Larger studies examining the effects of L-NMMA on mortality and morbidity are now required.
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Cardiovascular research · Jan 1994
Left ventricular remodelling and disparate changes in contractility and relaxation during the development of and recovery from experimental heart failure.
Canine pacing induced heart failure is characterised by impaired left ventricular contractility and relaxation, and clinical recovery after cessation of pacing. It is unclear whether the impairment is responsive to adrenergic stimulation. The aim of this study was to assess left ventricular contractility and relaxation and their response to beta adrenergic stimulation during heart failure and after recovery. ⋯ In pacing induced heart failure, there is a dissociation between the normal ability of beta adrenergic stimulation to augment contractility and shorten relaxation, and a differential capacity for recovery of contractility and relaxation.