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Biomedical subjects

V Ia Izakov

Publications and source records attributed to V Ia Izakov.

At least 55 records · Page 3Linked to original sources
PubMedDate not supplied

[Modeling atrial and ventricular contractility of the heart muscle. I. Modeling single contractions].

A system of differential equations describing myocardium contractions in isometric and isotonic regimes has been obtained. On the basis of these equations functioning of myocardium was modelled on an electronic computer. An effect has been revealed of the coefficients of rheological equations and activation function on isometric and isotonic contraction of the force/rate ratio. A good agreement between the results of modelling and the experimental data has been observed.

Biomechanical Phenomena↗
PubMedDate not supplied

[Influence of mechanical conditions on myocardial chronoinotropy].

The force-frequency relationships in isometric, isotonic and auxotonic regimes of contractions have been analysed in right rabbit papillary muscles. The uncorrelated Hauss input sequence of interstimulus intervals was used. For studied mechanical regimes a number of differences have been shown. These differences were in: 1) coefficients of contraction amplitude variation (with the same input stimulus dispersion); 2) dependence of mechanical activity upon the amplitude of previous contraction; 3) force-frequency relationships calculated with regression equations. The nature of revealed differences and usage of chronotropic indexes as a measure of contractility have been discussed.

Animals↗
PubMedDate not supplied

[Interaction between length and force in cardiac muscle. Electromechanical conjunction during myocardial deformation].

The influence of initial length upon the phasic and tonic components of contraction was investigated by modified sucrose gap method in myocardial specimens of frog atrium and ventriculum and in rabbit papillary muscles. The stretch of myocardial specimens was found to cause the shift in "current-force of contraction" curves towards lower values of depolarizing current. The relationship between phasic and tonic components was shown to depend upon the initial length of the heart muscle. It was suggested that changes in the membrane potential and proposed additional calcium activation play a major role in the myocardial length-tension relationship, as well as myofilaments overlapping.

Animals↗