The paper starts with a descripition of the development and the present status of the academy, laboratory and academic journals of Space Medicine, introduces an attempt to systemize the science, and goes on to review the new objectives of space medicine in the following order, based on the influence of weightlessness, the mechanism of life-support system and the influences of prolonged space life which were adopted as the next themes of the Bioastronautics Committee of the International Astronautical Federation, freely utilizing the findings of processors and the author himself.
1. Problems of hypodynamics.
2. Influences of prolonged exposure to high g.
3. The principles of locomotion in outer space.
4. Progress of the life support systems.
5. Biological problems in long termed space life, especially chronobiological problems.
6. Miscellaneous, drawing attention to the problems of radiation and the magnetic field, and introducing the actual monitoring of physiological functions during space mission.
7. Detection of primitive life.
I have endeavoured to show through the above how much depends on the technics of medical electronics, from remote control on information relaying by telemeteres, and disposal of data by computers to the physical and chemical analysis. It may be said that space medicine is the science of artificial environment which must be perfected by the cream of scientists in biotechnology.
By explaining the unique position and system of space medicine, I hope that a better understanding can be reached on space medicine as one applied field of medical electronics and biotechnology.

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This paper describes a new method and some results of automatic detection and classification of arrhythmias in coronary care unit, on a small scale NEAC-3200 computer.
There are many kinds of arrhythmias, but in this paper we deal with important arrhythmias, for example, cardiac arrest, ventricular fibrillation, paroxysmal ventricular tachycardia and so on, that are monitored in coronary care unit.
With each sample, the results have been satisfactory and the time required for computer diagnosis of arrhythmia was less than 0.45 seconds.
As a result of these studies, it became clear that automatic monitoring in coronary care units can be practised continuously by a small scale computer and be a boon to doctors and nurses, reducing their workload and strengthening their check on patients.

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This paper presents two approaches, which we tried, in order to raise the efficiency of assisting the left ventricle, by counterpulsation; 1) Devising a powerful pump; and 2) An ideal timing control of the pumping. Our pump is a pulsator, driven by compressed air, capable of flexible sucking and ejecting manoeuver.
Analyzing the parameters which contribute to the efficiency of assistance, we estimated mathematically, the pumping time adjustment, which would diminish the left ventricular work to the minimal degree. The parameters evaluated include : 1) Position of the catheter tip; 2) Optimal pump stroke volume, as a function of the cardiac stroke volume; 3) Timing of the sucking on; and 4) Sucking phase duration.
From these findings we have calculated and present η as the counterpulsation gain coefficient. Encouraged by experimental data, which well correlate with our estimation, automation by analogue computer has been done to obtain optimal η. By these procedures we have been able to decrease the left ventricular, TTI to about 10%. In other words, we have achieved atrialization of the left ventricle, and thus in this paper, we present more information concerning η.

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Algebraic and graphical analysis were performed for physical equilibriums in the circulatory system, in relation to the blood pressure regulation. 1. Linear relations for the small changes in pressures and volumes of major compartments of the circulatory system was studied, and the blood distribution to the compartments were obtained for the small change in the blood volume, and a concept of equivalent impedance of the heart was introduced. 2. Graphical analysis was shown for the nonlinear relation of the arterial pressure v. s. cardiac output, and for the blood distribution to the arterial and the venous system. 3. Equilibrium conditions of the colloid osmotic pressure and the capillary pressure were studied. Assuming that the cardiac function was unchanged, it is shown that a stable equilibrium condition was uniquely determined for any content of total plasma protein. 4. Graphical analysis was shown for the recovery process of plasma volume after hemorrhage.

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Time course of the changes in left ventricular pressure-volume coefficient in a cardiac cycle, defined as e (t) =p (t) /v (t), where t=time from the beginning of the cardiac cycle, p (t) = systolic intraventricular pressure and v(t) = systolic intraventricular volume, is studied on anesthetized and thoracotomized dogs. For actual computation, v (t) = (1-ρ) ^-1·v_s-∫^t₀i (t)dt, where ρ=residual volume ratio of the left ventricle measured by a thermodilution method, v_s= stroke volume and i(t) = ascending aortic blood flow by an electromagnetic flowmeter. It is demonstrated that e(t) is approximately independent from intraventricular end-diastolic volume and from conditions of the arterial system, but is characteristically dependent on the strength of cardiac sympathetic stimulation and heart rate.
A model of the left ventricular pumping is proposed with e(t), and the results of its theoretical analysis are in satisfactory agreement with many investigated relationships among circulatory variables in cardiovascular physiology.

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