Segmental blood flow through intramyocardial coronary arteries during ventricular systole.
The presented hypothesis assumes, in contrast with the currently prevailing view, that blood continues to flow through the coronary vascular bed even during systole. The contraction of differently oriented myocardial layers closes the penetrating branches of the coronary arteries in the interlayer boundaries. Coronary arteries of a different caliber are during systole under equal intramyocardial pressure. In accordance with the theory of elasticity, the action of an equal external pressure decreases with the lumen of the vessel and, thus, the net effect of these forces will push the blood into smaller vessels within the segment in the layer. This hydrodynamic effect empties the larger coronary arteries during systole so that they are ready for the subsequent massive influx of blood during diastole. The possible applications of this hypothesis in various physiological and pathological conditions are compatible with the present knowledge and might contribute to a more precise understanding of implicated pathophysiological mechanisms.
Hulín
I
I
Department of Clinical Pathophysiology of Medical School, Comenius University, Bratislava, Slovakia.
Slavkovský
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P
D001783:Blood Flow Velocity; D001794:Blood Pressure / Q000502:physiology; D003326:Coronary Circulation; D003331:Coronary Vessels / Q000502:physiology*; D006801:Humans; D013599:Systole / Q000502:physiology*