Epicardial coronary venous pressures: autonomic responses.

Intramyocardial, ventricular, aortic, and central and peripheral coronary artery as well as peripheral and central coronary venous pressures were measured simultaneously in dog hearts. A gradient of coronary vascular pressures was detected and quantitated. Stellate stimulation increased all pressures. Isoproterenol induced outflow tract obstructions so that aortic and central coronary artery pressures were unchanged while the other pressures increased. Vagal stimulation dissociated the intramyocardial venous pressure relationship in as much as arterial pressures decreased while epicardial coronary venous pressure was increased. These data suggest that coronary venous pressure in response to sympathetic stimulation increases as intramyocardial pressure increases. However, vagal stimulation permits a dissociation of these effects suggesting that coronary venous pressure regulation is complex.