Role of mechanical factors in the etiology of coronary insufficiency
Novikova, E.B.
Kardiologiia 16(2): 147-157
1976
ISSN/ISBN: 0022-9040 PMID: 787615 Document Number: 102630
Heart contractions create an obstacle for penetration of blood into coronary vessels. Under normal physiological conditions this hindrance is compensated by the functional and morphological characteristics of the coronary system of the endocardium and filling of the vessels during diastole. The hindrance, which is overcome in the norm, becomes a pathological factor when the coronary system loses its great reserve for expansion. As a result of loss of vasomotor regulation the mechanical conditions of the advance of the blood along the coronary vessels become the only regulating factor. They become worse upon intensification of cardiac activity and increase of the end diastolic pressure in the left ventricle. In this case the deterioration of perfusion is combined with an increase of the energy requirements of the heart, which leads to the occurrence of an acute O2 deficit. This mechanism of occurrence of ischemia of the myocardium during angina is confirmed by recent investigations of human coronary circulation.