The left ventricle as confocal prolate spheroids
Tóm tắt
A model of left ventricle is described which takes into account the physiologic variations of thickness, a function of time and distance prior to and during ejection, by assuming that the prolate spheroids are confocal at a given instant. The hyperbolic segment of arc between innermost and outermost spheroids, confocal with the latter, defines a so-called functional thickness, for which a derivation is given. Results show that this model operates in a range of eccentricity wherein thickness change per unit internal volume change are greatest.
Tài liệu tham khảo
Brady, A. J. 1968. “Active State in Cardiac Muscle”.Physiol. Rev.,48, 570–600.
Dieudonné, J. M. 1969. “La détermination expérimentale des contraintes myocardiques.”J. Physiol. (Paris), (In press).
Feigl, E. D. and D. L. Fry. 1964. “Myocardial Mural Thickness During the Cardiac Cycle.”Circulation Res.,14, 541–545.
Fisher, V. J., R. J. Lee, A. Gourin, H. Bolooki, J. H. Stuckey and F. Kavaler. 1966. “Muscle Fiber Length, a Determinant of Left Ventricular Contraction Pattern”.Am. J. Physiol.,211, 301–306.
Hawthorne, E. W. 1961. “Instantaneous Dimensional Changes of the Left Ventricle in Dogs”.Circulation Res.,9, 110–119.
— 1966. “Dynamic Geometry of the Left Ventricle”.Am. J. Cardiol.,18, 566–573.
Sandler, H., and H. T. Dodge. 1963. “Left Ventricular Tension and Stress in Man”.Circulation Res.,13, 91–104.
Scher, A. M. and A. C. Young. 1956. “The Pathway of Ventricular Depolarization in the Dog”.Circulation Res.,4, 461.
Vayo, H. W. 1967. “Fourier Series Analysis of Ventricular Dimensions”. InFactors Influencing Myocardial Contractility. New York: Academic Press. pp. 141–148.