The effect of sympathetic alpha-receptor coronary vasoconstriction on myocardial oxygen tension was studied in open- and closed-chest, chloralose-anesthetized dogs. Blood oxygen tension in the coronary sinus and blood flow in the circumflex coronary artery were continuously measured in a three-part experiment. With stimulation of the left stellate ganglion (15 Hz, 3 msec, 4-7 v, 90-second train...

BACKGROUND Phase contrast (PC) cine-magnetic resonance imaging (MRI) of the coronary sinus allows for noninvasive evaluation of coronary flow reserve (CFR), which is an index of left ventricular microvascular function. The objective of this study was to investigate coronary flow reserve in patients with heart failure with preserved ejection fraction (HFpEF). METHODS AND RESULTS We studied 25 ...

Changes in intramyocardial tissue pressure modulate the relationship between coronary pressure and flow during the cardiac cycle. The present study compared the relation between measured and calculated diastolic subendocardial tissue pressure and coronary pressure at zero flow in anesthetized dogs after modulation of either coronary sinus (i.e. Fogarty catheter) or left ventricular intracavity ...

By integrating phasic coronary sinus flow curves in such a way that volume flow during systole plus isometric contraction and that during the remainder of diastole can be compared, the relative contribution of ventricular compression and coronary resistance to mean coronary flow can be assessed. It was found that anoxia, adenylic acid, compression of the aorta or pulmonary artery reduces corona...

I read with interest the article of De Paulis et al. “Coronary flow characteristics after a Bentall procedure with or without sinuses of Valsalva” in the July 2004 issue of the European Journal of Cardiothoracic Surgery [1], which examines the effects of the pseudosinuses of a ‘new conduit’ with pseudosinuses (Gelweave Valsalvae, Terumo Vascutek, Renfrewshire, Scotland, UK) upon coronary blood ...

The echocardiographic features of the enlarged coronary sinus are described in eight patients with a left superior vena cava draining to the coronary sinus and two patients with total anomalous pulmonary venous connection to the coronary sinus. The diagnosis was confirmed in each patient by cardiac catheterization and surgery. On the M-mode echocardiogram, a dense echo was present posterior to ...

Cardiac magnetic resonance imaging (CMR) demonstrated a sinus of Valsalva aneurysm (SVA) with severe dilatation of the right coronary sinus in association with a congenital bicuspid aortic valve (BAV) and sub-aortic membrane. The SVA had not been apparent on echocardiography as the dilatation was outside standard echo image planes. On both CMR and echo, blood flow was eccentrically directed int...

Control of the coronary circulation by the carotid sinus was studied in intact, unanesthetized dogs instrumented with Doppler ultrasonic flow probes on the left circumflex coronary artery, miniature pressure gauges in the aorta, and stimulating electrodes on the carotid sinus nerves. A radiofrequency pacemaker was used to stimulate the nerves in dogs at rest, during sleep, exercise, and after a...

OBJECTIVE To assess the importance of 2,3-diphosphoglycerate (2,3-DPG) and oxygen-haemoglobin binding to oxygen transport in patients with congestive heart failure. METHODS In 30 patients with severe congestive heart failure, arterial, mixed venous, and coronary sinus venous blood concentrations of 2,3-DPG were measured and systemic output and coronary sinus blood flow were measured by a ther...