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Iu P Zolkin

Publications and source records attributed to Iu P Zolkin.

4 recordsLinked to original sources
PubMedDate not supplied

[Methods and modern apparatus for assisted circulation. The basic trends in their development].

A systematization of methods for assisted circulation, based on the formulation of a concrete procedure, the nature of the deranged or lost function substitution and conditions for effective realization of such a substitution, is offered. This made it possible to classify the equipment for assisted circulation and to analyze the current trends of its further development. The most characteristic automation levels of the equipment under consideration and of generations of some apparatus, differing in the degree of automation, control and monitoring the process of assisted circulation, are presented in the form of tables and pictures.

Assisted Circulation↗
PubMedDate not supplied

[Methods of cardiac synchronization in assisted circulation].

In assisted circulation cardiosynchronization should be regarded as a process of monitoring the arterial blood pressure within the limits of the cardiac cycle and changes of its form with the aim of improving the energy balance of the heart. The coordination of the pumping function and that of the cardio-vascular system comes to a problem of shaping the monitoring action that depends upon three variables, viz. the time lag tepsilon, actuation of the unit relative to the base cardiosignal, duration of the pumping phase tpi and the signal level at the pump's inlet U(t). A number of researchers consider tepsilon and tpi to be a function of the cardiac contractions period and determine them in different ways, employing for this purpose extrapolation, stochastic characteristics, etc. Of late, in addition to the period of cardiac contractions extremal, mean integral values of the systolic and diastolic pressure, the level of pressure at the instant of the cardiac valves closure and others have also come in use. There are shortcomings in the proposed cardiosynchronization algorhythms: their empiric nature and also the fact that the monitoring action includes merely variables tepsilon and tpi and does not carry function U(t), which reflects the intensity of the pump's operation.

Assisted Circulation↗
PubMedDate not supplied

[Hydrodynamic stands for testing assisted circulation and artificial heart apparatus].

Problems arising in devising the assisted circulation apparatus and artificial heart can be solved only with investigations conducted on hydrodynamic models of the circulation system--the stands. An analysis of literature sources dealing with test stands justifies their classification according to the purpose, the types of tests, the specific structure and basic characteristics. It is necessary to proceed with further improvement of the stand equipment in the direction of creating a sufficiently accurate imitation of the anatomic structure and resilient properties of major arteries and veins, of constructing a geometrical and elastic model of the aorta, of pressure and flow control instruments at different points of the vessels, of the ones regulating the energy parameters, as well as of working out criteria for effectiveness of the devices to be used.

Assisted Circulation↗