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UNLABELLED [1-Carbon-11]acetate has been used as a tracer for oxidative metabolism with PET. The aim of this study was to validate, in humans, a previously proposed two-compartment model for [1-11C]acetate for the noninvasive measurement of myocardial oxygen consumption (MVO2) and myocardial blood flow (MBF) with PET. METHODS Twelve healthy volunteers(More)
The effects of altitude on coronary patients with impaired left ventricular function are virtually unknown and the question arises whether an exposure to altitude poses a risk to such patients. Twenty-three patients with coronary artery disease (mean age 51 +/- 9 years; group H) with a mean ejection fraction of 39 +/- 6% were compared with 23 normal(More)
UNLABELLED PET with 13N-ammonia permits the noninvasive quantification of myocardial blood flow (MBF) in humans. The present study was done to assess the reproducibility of quantitative blood flow measurements at rest and during pharmacologically induced hyperemia in healthy individuals. METHODS Thirty healthy volunteers (26 men, 4 women) were studied.(More)
BACKGROUND Cardiovascular conditioning reduces resting myocardial oxygen demand by lowering systolic blood pressure and heart rate. Lower myocardial oxygen demand at rest would be expected to be associated with a decrease in resting myocardial blood flow and, consequently, an increase in myocardial flow reserve as the ratio of hyperemic to resting blood(More)
BACKGROUND This investigation examines the effects of inotropic stimulation on myocardial blood flow (MBF) and glucose metabolism (MRGlc) in dysfunctional myocardium through the use of positron emission tomography (PET). METHODS AND RESULTS Nineteen patients with chronic coronary artery disease and 12 normal volunteers were studied with 13N-ammonia,(More)
BACKGROUND Cigarette smoking is a major preventable risk factor for coronary artery disease and sudden cardiac death. However, the effect of acute and long-term cigarette smoking on coronary vasodilatory capacity and myocardial flow reserve has not been quantified in humans. METHODS AND RESULTS To examine the effect of short-term and long-term smoking,(More)
UNLABELLED The beta 1 receptor blockade reduces cardiac work and may thereby lower myocardial blood flow (MBF) at rest. The effect of beta 1 receptor blockade on hyperemic MBF is unknown. METHODS To evaluate the effect of selective beta 1 receptor blockade on MBF at rest and during dipyridamole induced hyperemia, 10 healthy volunteers (8 men, 2 women,(More)
Physical stress might modulate myocardial blood flow in near-maximally dilated coronary arteries by increasing coronary perfusion pressure, myocardial contractility, and heart rate. The net effect of these changes on hyperemic blood flows has not yet been defined in humans. To quantify the effect of physical exercise on pharmacologically induced hyperemia,(More)
UNLABELLED Although [1-11C]acetate has been validated as a PET tracer for myocardial oxygen consumption (MVO2) in animals and humans, mono- and biexponential fitting of the tissue time-activity curve yields only estimates of MVO2. This study attempts to develop and validate a simple tracer kinetic model in vivo for estimation of regional MVO2. METHODS(More)
UNLABELLED Stress testing with intravenous injection of dipyridamole is frequently used for noninvasive detection of coronary artery disease (CAD) with PET or SPECT. Dietary intake of caffeinated food, beverages or medication might alter both resting and dipyridamole-induced hyperemic blood flow, thereby compromising the diagnostic sensitivity of(More)