Z-scores of early diastolic blood flow widths of mitral and tricuspid valves in normal fetuses and fetuses with dilated coronary sinus

alpha-Adrenergic control of the oxygen delivery to the myocardium during exercise was investigated in eight conscious dogs instrumented for chronic measurements of coronary blood flow, left ventricular (LV) pressure, aortic blood pressure, and heart rate and sampling of arterial and coronary sinus blood. After alpha-adrenergic receptor blockade a standard exercise load elicited a significantly greater increase in heart rate, rate of change of LV pressure (LV dP/dt), LV dP/dt/P, and coronary blood flow than was elicited in the unblocked state. In contrast to the response pattern during control exercise, there was no significant change in coronary sinus oxygen tension (PO2), myocardial arteriovenous oxygen difference, and myocardial oxygen delivery-to-oxygen consumption ratio. It is concluded that the normal relationship between myocardial oxygen supply and oxygen demand is modified during exercise after alpha-adrenergic blockade, whereby oxygen delivery is better matched to oxygen consumption. These results indicate that the increase in coronary blood flow and oxygen delivery to the myocardium during normal exercise is limited by alpha-adrenergic vasoconstriction.

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Krypton 85 myocardial blood flow: precordial scintillation versus coronary sinus sampling

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1965.209.4.705 ◽

1965 ◽

Vol 209 (4) ◽

pp. 705-710 ◽

Cited By ~ 34

Author(s):

Michael D. Klein ◽

Lawrence S. Cohen ◽

Richard Gorlin

Keyword(s):

Blood Flow ◽

Myocardial Blood Flow ◽

Coronary Sinus ◽

Human Subjects ◽

Radioactive Decay ◽

Empirical Correction ◽

Wide Range ◽

Actual Flow ◽

Flow Through ◽

High Degree

Myocardial blood flow in human subjects was assessed by comparative simultaneous measurement of krypton 85 radioactive decay from coronary sinus and precordial scintillation. Empirical correction of postclearance background from precordial curves yielded a high degree of correlation between flows derived from the two sampling sites (r = .889, P < .001). Comparison of left and right coronary flows in nine subjects revealed similarity in flow through the two vessels over a wide range of actual flow values (r = .945, P < .001).

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Reply to: “The importance of evaluating coronary sinus blood flow during the coronary sinus reducer treatment”

International Journal of Cardiology ◽

10.1016/j.ijcard.2021.04.056 ◽

2021 ◽

Author(s):

Francesco Giannini ◽

Francesco Ponticelli ◽

Stefano Guarracini ◽

Georgios Tzanis

Keyword(s):

Blood Flow ◽

Coronary Sinus ◽

Coronary Sinus Blood ◽

Coronary Sinus Blood Flow

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Measurement of Coronary Sinus Blood Flow by Continuous Thermodilution in Man

Circulation ◽

10.1161/01.cir.44.2.181 ◽

1971 ◽

Vol 44 (2) ◽

pp. 181-195 ◽

Cited By ~ 727

Author(s):

WILLIAM GANZ ◽

KOHJI TAMURA ◽

HAROLD S. MARCUS ◽

ROBERTO DONOSO ◽

SHINJI YOSHIDA ◽

...

Keyword(s):

Blood Flow ◽

Coronary Sinus ◽

Coronary Sinus Blood ◽

Coronary Sinus Blood Flow

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Alteration in myocardial oxygen balance during exercise after beta-adrenergic blockade in dogs

Journal of Applied Physiology ◽

10.1152/jappl.1980.49.1.28 ◽

1980 ◽

Vol 49 (1) ◽

pp. 28-33 ◽

Cited By ~ 30

Author(s):

G. R. Heyndrickx ◽

J. L. Pannier ◽

P. Muylaert ◽

C. Mabilde ◽

I. Leusen

Keyword(s):

Heart Rate ◽

Blood Flow ◽

Oxygen Consumption ◽

Myocardial Blood Flow ◽

Coronary Blood Flow ◽

Coronary Sinus ◽

Myocardial Oxygen Consumption ◽

Left Ventricular ◽

Adrenergic Blockade ◽

Oxygen Balance

The effects of beta-adrenergic blockade upon myocardial blood flow and oxygen balance during exercise were evaluated in eight conscious dogs, instrumented for chronic measurements of coronary blood flow, left ventricular pressure, aortic blood pressure, heart rate, and sampling of arterial and coronary sinus venous blood. The administration of propranolol (1.5 mg/kg iv) produced a decrease in heart rate, peak left ventricular (LV) dP/dt, LV (dP/dt/P, and an increase in LV end-diastolic pressure during exercise. Mean coronary blood flow and myocardial oxygen consumption were lower after propranolol than at the same exercise intensity in control conditions. The oxygen delivery-to-oxygen consumption ratio and the coronary sinus oxygen content were also significantly lower. It is concluded that the relationship between myocardial oxygen supply and demand is modified during exercise after propranolol, so that a given level of myocardial oxygen consumption is achieved with a proportionally lower myocardial blood flow and a higher oxygen extraction.

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