Effect of Heart Rate and Intracoronary Isoproterenol, Levarterenol, and Epinephrine on Coronary Flow and Resistance

Lewis, F; Coffman, Jay D.; Gregg, Donald E.

doi:10.1161/01.res.9.1.89

Cited by 42 publications

(10 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Similar findings have been reported by other investigators (12,19,21). In view of the known relationships between heart rate and other cardiac contractile events, myocardial oxygen consumption, and coronary blood flow (1,16,17,22,23), these actions of propranolol would be expected to reduce the cardiac work load, myocardial oxygen requirement, and therefore, the metabolic stimulus for compensatory dilatation of the coronary vascular bed (24). The resulting "passive" coronary vasoconstriction, supplemented by blockade of /3-adrenergic vasodilator receptors in the coronary vascular bed (4,25), could account for the increase in coronary vascular resistance observed after propranolol in this and previous reports, and for the reduction in coronary blood flow reported by other investigators (2,6,12,19).…”

Section: Discussionsupporting

confidence: 88%

“…The negative inotropic and depressor responses to propranolol occurred during the period when heart rate was maintained constant; only negligible changes occurred when electrical pacing was stopped and the heart rate was allowed to decrease. The secondary increase in coronary resistance is presumably due to a lower myocardial oxygen consumption associated with the reduced heart rate (16,17), rather than to any physical influence of the negative chronotropic action. The total increase in coronary vascular resistance (+40.3%) agrees with that obtained in the control group (Table 1).…”

Section: Effects Of Intravenous D|propranololmentioning

confidence: 99%

See 1 more Smart Citation

Effects of Propranolol and Its Stereoisomers upon Coronary Vascular Resistance

Whitsitt

Lucchesi

1967

Circulation Research

View full text Add to dashboard Cite

Responses of the coronary vascular bed to propranolol and its stereoisomers were studied in dogs anesthetized with allobarbital and urethane. The circumflex coronary artery was cannulated and perfused at a constant rate with blood from a femoral artery, coronary perfusion pressure being monitored as an index of coronary vascular resistance. dl -Propranolol (0.5 mg/kg iv) increased coronary vascular resistance and simultaneously reduced myocardial contractile force, heart rate, and systemic blood pressure. Approximately two thirds of the increase in coronary resistance was associated with the negative chronotropic action of propranolol. Intracoronary injections of dl -propranolol and l -propranolol increased coronary vascular resistance; d -propranolol increased resistance after an initial transient coronary dilatation. Intracoronary injections reduced contractile force in the pump-perfused area, but were without effects on heart rate and blood pressure. Reserpine pretreatment reduced, but did not abolish, the coronary vascular response to systemic propranolol; the chronotropic and inotropic responses were abolished. The responses to intracoronary d -propranolol were not altered. It was concluded that the increase in coronary vascular resistance following propranolol is due largely to the negative chronotropic effect of the drug and to an action of the drug which is unrelated to specific β-adrenergic receptor blockade.

show abstract

Section: Discussionsupporting

confidence: 88%

Section: Effects Of Intravenous D|propranololmentioning

confidence: 99%

Effects of Propranolol and Its Stereoisomers upon Coronary Vascular Resistance

Whitsitt

Lucchesi

1967

Circulation Research

View full text Add to dashboard Cite

show abstract

“…In contrast, isoprenaline, because of its powerful beta-adrenergic effects, would be expected to dilate coronary arterial vessels. This effect has been reported in previous studies (Lewis et al, 1961;Greenfield et al, 1972). Tuttle and Mills (1975) showed that dobutamine, unlike dopamine, exerts its inotropic effect directly on the myocardium and not by the release of endogenous catecholamines.…”

Section: Discussionsupporting

confidence: 84%

Haemodynamic effects of dobutamine with special reference to myocardial blood flow. A comparison with dopamine and isoprenaline.

Stephens¹,

Ead²,

Spurrell³

1979

Heart

View full text Add to dashboard Cite

SUMMARY The haemodynamic effects of dobutamine (2.5 to 10 ug/min per kg) were determined in 5 patients without cardiac failure who were undergoing cardiac catheterisation for suspected coronary disease. Myocardial blood flow was determined by the coronary sinus thermodilution technique. Data were compared with those from two groups of 5 patients who received dopamine (4-8 ,ug/min per kg) and isoprenaline (0.005-0.025 ,ug/min per kg). Each drug was given in a lower and a higher dose, and all increased mean cardiac index (dobutamine, 18% and 39%; dopamine, 11% and 23%; isoprenaline, 15% and 44%). These increases were associated with significant increases in mean myocardial oxygen consumption (dobutamine, 38% and 61%; dopamine, 25% and 62%; isoprenaline, 20% and 45%). Mean myocardial blood flow was increased by each drug but mean myocardial oxygen extraction was decreased by isoprenaline, was increased by dopamine, and was unchanged by dobutamine. Each inotropic agent has a similar effect on myocardial oxygen consumption, but isoprenaline has a direct coronary vasodilator action while dopamine has a coronary vasoconstrictor action. Dobutamine has no direct effect upon coronary vascular tone.

show abstract

“…• Isoproterenol increases coronary flow when coronary perfusion pressure is maintained constant by artificial systems (1,2). With the circulation intact, however, the initial marked increase in coronary flow is often interrupted by a sharp decrease in flow to near control levels, and this can occur when other effects of isoproterenol such as heart rate are reaching peak level.…”

Section: Additional Abstractmentioning

confidence: 99%

Limitation of Myocardial Function by Reduced Coronary Blood Flow during Isoproterenol Action

Daniell

Bagwell

Walton

1967

Circulation Research

View full text Add to dashboard Cite

The interpolated decrease in heart force or isometric systolic tension that occurs during isoproterenol stimulation has been examined in terms of changes in coronary flow and myocardial metabolism. In 67 open-chest dogs under pentobarbital anesthesia, determinations were made of lactate, pyruvate, Po 2 and Pco 2 in arterial and coronary sinus blood; coronary flow was measured with an electromagnetic flow transducer and ventricular force with a strain gauge arch. Although the characteristic, uncomplicated effect of isoproterenol is a marked increase in coronary flow and contractile force, this is briefly interrupted by a sharp decrease in these functions, and the decrease is associated with evidence of anaerobic metabolism. This decrease is concomitant with decreased coronary perfusion pressure and is intensified by sustained infusion of isoproterenol or by lowered oxygen concentrations in the inspired air. The stage of depressed function is counteracted by mechanical maintenance of high aortic pressure or by slow, controlled heart rate. When uncontrolled, tachycardia due to isoproterenol continues without phasic interruption. The intermediate period of depressed function is interpreted in terms of sharply decreased oxygen delivery when both cardiac rate and force are increased. The hemodynamic and metabolic values for these acutely occurring, reversible extremes have been specified.

show abstract

Effect of Heart Rate and Intracoronary Isoproterenol, Levarterenol, and Epinephrine on Coronary Flow and Resistance

Cited by 42 publications

References 13 publications

Effects of Propranolol and Its Stereoisomers upon Coronary Vascular Resistance

Effects of Propranolol and Its Stereoisomers upon Coronary Vascular Resistance

Haemodynamic effects of dobutamine with special reference to myocardial blood flow. A comparison with dopamine and isoprenaline.

Limitation of Myocardial Function by Reduced Coronary Blood Flow during Isoproterenol Action

Contact Info

Product

Resources

About