OBJECTIVE To examine the role of the sympathetic nervous system in regulating insulin's action on coronary perfusion in uncomplicated type 1 diabetes by blocking centrally mediated sympathetic activity with dexamethasone. METHODS Positron emission tomography and oxygen 15 labelled water were used to quantify myocardial blood flow basally and during adenosine infusion with or without simultane...

Disclaimer This health technology scientific literature review was prepared by the Medical Advisory Secretariat, Ontario Ministry of Health and Long-Term Care arising from analysis, interpretation and comparison of scientific research and/or technology assessments conducted by other organizations. While every effort has been made to do so, this document may not fully reflect scientific research...

Patients with atrial fibrillation (AF) frequently present with symptoms suggestive of myocardial isch- aemia, even in the absence of significant CAD, that seem to be attributable to abnormalities of myocardial perfusion and perfusion reserve. According to the results of recent human and previous experimen- tal studies the increase in coronary artery blood flow during AF is smaller, while the co...

BACKGROUND Myocardial perfusion reserve can be noninvasively assessed with cardiovascular MR. In this study, the diagnostic accuracy of this technique for the detection of significant coronary artery stenosis was evaluated. METHODS AND RESULTS In 15 patients with single-vessel coronary artery disease and 5 patients without significant coronary artery disease, the signal intensity-time curves ...

Background Our study compares the effect of acute proximal stenosis of a coronary artery supplying a myocardial perfusion bed with that of stenosis of an adjacent artery resulting in collateral flow diversion supplied by the same perfusion bed. These alterations in coronary physiology were quantified by digital angiographic impulse response analysis of contrast material mean transit time for th...

In severe coronary artery disease (CAD), it has been shown that intramyocardial inotropic reserve as assessed with tagged magnetic resonance imaging (MRI) is uniformly distributed among positron emission tomography (PET) patterns reflecting normal or concomitant reductions in perfusion and glucose metabolism. This preliminary study aimed to delineate the relationship between preoperative values...

Background and Purpose—Patients with carotid occlusive disease and stage 2 cerebral hemodynamic failure, characterized by an increased oxygen extraction fraction (OEF) as measured by positron emission tomography (PET) and otherwise known as misery perfusion, have a high risk of cerebral ischemia and subsequent stroke. In clinical practice, the detection of patients with misery perfusion through...

BACKGROUND AND PURPOSE Patients with carotid occlusive disease and stage 2 cerebral hemodynamic failure, characterized by an increased oxygen extraction fraction (OEF) as measured by positron emission tomography (PET) and otherwise known as misery perfusion, have a high risk of cerebral ischemia and subsequent stroke. In clinical practice, the detection of patients with misery perfusion through...

Background Echo and nuclear studies have shown that coronary flow changes with the cold pressor test (CPT). CPT has been used to measure coronary flow response because it provides an endothelium-dependent coronary vasodilation that is sensitive for detecting early changes in coronary endothelial function. There was also a study showed myocardial perfusion increases during CPT with first pass pe...