The present investigation was undertaken to study cardiac release of adenosine and prostacyclin (prostaglandin [PG] I2) in patients with ischemic heart disease (IHD), and to assess coronary vascular resistance before and after inhibition of synthesis in such patients. In 48 patients with IHD, arterial and coronary sinus blood samples were taken at rest, during atrial pacing to angina, and after...

We examined the late coronary vascular response to carotid chemoreceptor reflex activation in normal, conscious dogs instrumented for the measurement of right main and left circumflex coronary artery blood flows, arterial and right ventricular pressures, and arterial and coronary sinus blood gases and O2 contents. With heart rate held constant by electrical stimulation, and with respiration con...

Assessment of coronary blood flow and the vasodilator reserve capacity of individual coronary arteries in the catheterization laboratory has been hampered by methodologic limitations. We have developed and validated a small Doppler catheter that can subselectively measure phasic coronary blood flow velocity (CBFV). In seven anesthetized calves, CBFV was varied from 0.1 to 5.7 times control CBFV...

Phasic red cell velocity and diameters of coronary arterioles, capillaries, and venules were measured in the beating turtle and dog heart using high-speed cinematography with transillumination of the left ventricle. In the turtle, arteriolar red cell velocity was diminished during systole, but during diastole arteriolar inflow increased, especially during the rapid and the slow filling period. ...

We report the case of a rare anomaly of the right coronary artery (RCA) arising from the left aortic sinus, having a single ostium with the left coronary artery, associated with documented episodes of inferior ischemia, in which surgical treatment with a right internal thoracic artery to RCA bypass graft and the corresponding ligation provided greater stability to the coronary blood flow and go...

Assessment of coronary blood flow and the vasodilator reserve capacity of individual coronary arteries in the catheterization laboratory has been hampered by methodologic limitations. We have developed and validated a small Doppler catheter that can subselectively measure phasic coronary blood flow velocity (CBFV). In seven anesthetized calves, CBFV was varied from 0.1 to 5.7 times control CBFV...

We tested the hypothesis that potassium ion (K+) is involved in the local control of the coronary circulation. The left coronary artery was perfused at constant flow in closed-chest, anesthetized dogs. Step increases in heart rate caused transient (six dogs) or sustained (three dogs) increases in coronary sinus plasma [K+] averaging 0.53 mEq/liter. When the effects of vascular transit delay wer...

Background Previous studies using positron emission tomography demonstrated that decrease in global coronary flow reserve (CFR) predisposes to major cardiac events in patients with coronary artery disease. However, the value of MR assessment of CFR has not been clarified for predicting future cardiac events in hypertrophic cardiomyopathy (HCM). The purpose of this study was to evaluate a progno...

ATP-sensitive potassium (K+ATP) channels have been shown to play a role in the maintenance of basal coronary vascular tone in vivo. K+ATP channels are also involved in the coronary vasodilator response to adenosine. The aim of this study was to determine the role of K+ATP channels in local metabolically mediated increases in coronary blood flow during cardiac electrical paired pacing without ca...

Coronary artery anomalies are among the neglected topics in cardiology. Anomalous origin of the left main coronary artery from the right sinus of valsalva is a rare coronary anomaly observed in 0.15% of patients. During exercise, the distended aorta and pulmonary artery with increased blood flow may squeeze the Left Main Coronary Artery (LMCA) between them. Even though arrhythmias are common ca...