1) The hemodynamics in 42 old hypertensive subjects without complications of cardiac origin or of any other cause was examined using dye-dilution method. 2) The hemodynamics in old hypertensive subjects showed, in general, the slightly-10w cardiac output-high peripheral vascular resistance pattern. 3) When the effect of age was examined in these old hypertensive subjects, a decrease in stroke index was evident with advancing age. The wasting influence of aging on the left ventricular function became more marked after seventy, though the latter was fairly well maintained without apparent signs of cardiac decompensation. 4) Both cardiac index and stroke index decreased when mean blood pressure became higher. It was suggested that the left ventricle was "relatively over-loaded". 5) Age, per se, was a most important factor in determining the hemodynamics in old hypertensive subjects. It was suggested, moreover, that systolic blood pressure affected the left ventricular function, especially stroke index, much more than diastolic blood pressure did.

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The bidirectional ultrasonic Doppler method enables one to detect transcutaneously the flow patterns in blood vessels. The velocity spectrum consisting of various velocity components in the vessel can be shown by sound spectrography. 2. In healthy subjects, the arterial blood flow pattern of a single pulse cycle consisted of a rapid early forward flow which was usually followed by a small reverse phase, and a subsequent forward flow in diastole. It was noted that the conversion phase of flow direction showed a simultaneous existence of forward and reverse in the vessel. 3. The arterial flow pattern in such diseases as aortic regurgitation, aortitis syndrome and idiopathic hypertrophic subaortic stenosis showed respective features. 4. Venous flow patterns were also examined. The flow pattern in the internal jugular vein consisted of two peaks in a pulse cycle. This fundamental pattern was easily modified by certain physiological or pathological conditions.

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When venous return to the right heart was acutely impeded in anesthetized dogs with intact vagus nerves by inflating a balloon in the right atrium, the mean circulatory pressure rose, indicating a decrease in the capacitance of the circulatory system, thus confirming the present author's earlier observation. Since this response could be elicited to an equal extent after the elimination of the carotid sinus reflex, this response is probably due to mechanisms other than the carotid sinus reflex. When venous return to the left heart was impeded similarly by a balloon in the left atrium, the mean pulmonary arterial wedge and left atrial pressure rose, in the absence of appreciable changes in the volume of blood measured as existing between the pulmonary artery and left atrium, suggesting a decrease in the capacitance of the pulmonary circulatory system. An equation was derived that gives, under several simplifying assumptions. the slope (static) compliance. ΔV/ΔP, of the pulmonary "venous" system in terms of hemodynamic parameters measurable from pulmonary arterial wedge pressure tracings. On this basis, relative distensibility, (ΔV/ΔP)/V, of the pulmonary "veins" of anesthetized dogs was tentatively estimated to be about 0.026 (mmHg)^-1 at mean pulmonary artery wedge pressure of about 8 mmHg.

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1. A theoretical and a transformed formula was derived as to what extent RV outflow tract stenosis should be relieved to lower RV/LV pressure ratio below a certain value post-operatively in corrective surgery of tetralogy of Fallot. Values obtained from the theoretical formula correlated well with actual values in thirteen cases operated on. Relationship between degree of constriction and pulmonary flow was analyzed graphically. Experiments showed that critical stenosis was reached at the smaller degree of circumference constriction at greater thickness to circumference ratio of the pulmonary artery. Theoretical and experimental results were not concordant as to flow through Blalock and Waterston anastomosis. Further study should be required.

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Considering the configulation of the stenotic mitral valve orifice as a sort of pipe orifice in the hydraulic system, the above-mentioned formula has been derived from the usual form of continuity equation and energy equation. Vena contracta has not been cuased by the configulation of mitral orifice in about fifty-one percent of mitral stenosis. This result is different from Gorlin's one. The reasons why vena contracta was not brought about in the small mitral valve orifice as follow; the greater part of the mitral valve orifices were situated downward from the annulus and considered as so-called nozzled shape; there are little precision in the measurement of blood flow and pressure; mitral valve orifices themselves have various configulations. And so flow coefficient C is not constant such as Gorlin's formula, but a function of Reynolds number and throat area ratio. This coefficient is attributable to the configulation of the mitral orifice, the velocity of mitral valve flow and the viscosity of blood flow.

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The spatial velocity electrocardiogram (SVECG) was recorded in 61 subjects of normal men by the spatial velocity electrocardiograph manufactured by Mori et al. using Frank system simultaneously recorded with its scalar ECG's. Atrial component of the SVECG was analyzed quantitatively as well as qualitatively. The normal atrial SVECG is composed of three patterns: two-peaked, three-peaked and four-peaked patterns. The third and/or fourth peaks are the tallest in normal subjects. It can be considered that the first peak reflects the excitation of the right atrium, the second peak do those of the interatrial septum and both atria, and the third and fourth peaks reflect principally the depolarization of the left atrium and a part of the atrial repolarization. Two-peaked pattern is also recorded in few cases of normal subjects. In the two-peaked group the first peak contains the right or both atrial components and the second peak reflects mainly the left atrial excitation, and then both peaks cannot be thought simply to reflect the activation of right and left atria. The two-peaked pattern manifests the uniformity in inscription velocity of the efferent and afferent limbs of the spatial P loop because of its smooth and elliptic or linear configuration.

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The SVECG was recorded in grand total of 119 cases with mitral stenosis in 35 cases, atrial septal defect in 51 cases, tetralogy of Fallot in 22 cases and pulmonary stenosis in 11 cases, and the correlation with hemodynamic data in 107 cases and operation findings in 78 cases was investigated. The atrial SVECG in atrial overloadings is composed of 3 types as seen in normal subjects: two-peaked, three-peaked and four-peaked patterns. In the atrial SVECG of left atrial overloading, the first peak was considered to reflect the activation of right atrium and did not increase significantly in amplitude compared with normal subjects. The spatial velocity and time interval of the third and/or fourth peaks, which were considered to reflect mainly the depolarization of the left atrium, increased significantly. The P₃/P₁ and P₄/P₁ ratios had positive correlates with the mitral valvular area ascertained at surgical operation. The atrial SVECG represents the right atrial overloading as a two-peaked pattern. Its incidence was high as in ASD group (65%) as in TF (73%) and PS (73%) groups in spite of significantly lower right ventricular systolic pressure in ASD group than in TF and PS groups (P<0.01 and P<0.01 respectively). In TF group the right ventricular systolic pressure was significantly higher in the two-peaked subgroup than in the three-peaked one (P<0.05).

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For the evaluation of cardiac function in patients with cardiovascular diseases, classification of functional capacity by New York Heart Association (NYHA) based on subjective symptoms is available. However, the evaluation of cardiac function should be carried out as objectively as possible. Miyake from this Department used Master's 2-steps to give a load for 3 and 10 minutes and reported that a long term loading is not always necessary for the evaluation of cardiac function and loading for a prolonged period could be dangerous. In order to examine the problem of the duration of loading more objectively, the author used a thredmill, instead of Master's 2-steps to give a load for 3 and 10 minutes to the same patient with cardiovascular disease. Along with 12 healthy normal subjects, 9 patients with hypertension, 19 patients with valvular heart diseases, and 25 patients with coronary heart diseases under treatment on ambulant basis or during hospitalization were studied. According to the NYHA classification of functional capacity, 13 were classified as I, 22 as II, 18 as III and 12 as normal, giving the total of 65 cases. Loading was given on a treadmill with a grade of 5° and 30 meters per minute for 3 and 10 minutes. Continuous recording was carried out Evaluation of Cardiac Function, with 2-channel electrocardiograph. Expired air was obtaind into Douglas-bag before, during and after exercise for analysis with Scholander's microgas-analyzer to calculate relative metabolic rate (RMR), physical fitness index (PFI), oxygen debt and oxygen pulse. Arterial blood gas was analyzed using capillary blood and lactic acid in the venous blood was also analyzed. As the signs for stopping exercise, marked dyspnea, palpitation or chest pain were chosen and exercise was immediately stopped upon appearance of these symptoms. The criterion for discontinuation of exercise was set at ST depression or elevation of 2.0 mm more than the pre-loading level, and upon frequent occurrence of premature beats or appearance of paroxysmal tachycardia. Repro-ducibility of these loadings was also studied.

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In order to study the problem whether it is possible to differentiate normal subjects from class I or class I from class II in classification of functional capacity by New York Heart Association (NYHA) through increasing the amount of loading, though the report I showed the difficulty of such differentiation by moderate exercise load, multiple load test using treadmill was carried out in patients with cardiovascular diseases of class I, II and III of NYHA, along with normal subjects. Whether or not steady state exercise may be developed in cases of class III, with relatively poor cardiac function, through decreasing exercise load was also studied. Along with 8 normal subjects, 15 patients with hypertension, 25 patients with coronary heart disease and 16 patients with valvular heart diseases under treatment on ambulant basis or during hospitalization were employed. According to NYHA classiflcation of cardiac function, 18 were classified as I, 25 as II, 13 as III, and 8 as normal, giving the total of 64 cases. Loading was given on a treadmill with a grade of 5° and 30 meters per minutes for 10 minutes (moderate). In cases in which 10 minutes loading was completed, loading at a grade 10° and 50 meters per minute for 10 minutes (intense) was given after more than 30 minutes of rest. In cases in which 10 minutes moderate exercise could not be carried out. loading at a grade of 2.5° and 20 meters per minute for 10 minutes (mild) was given. As descrived in report I, continuous observation with the use of 2-channel ECG was carried out. Expired air was continuosly sampled before, during and after loading and analyzed with Scholander's microgas-analyzer, to calculate relative metabolic rate (RMR), physical fitness index (PFI), oxygen debt and oxygen pulse.

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Glucagon, a polypeptide hormone produced chiefly by the alpha cells of the pancreas, has been used clinically for the treatment of heart failure and cardiogenic shock because of its positive inotropic capabilities. In almost of the previous investigations, glucagon in dosis of 50-70μg/Kg was infused in the patient by an infusion pump over a two minute period and the evaluation of its effects was carried out with maximum response of hemodynamics. However, peak effect of glucagon infusion was only between 10 and 15 minutes, and the previous evaluation of effects of glucagon had some problems on the special case who needs prolonged effect of glucagon. In the preliminary study, the authors found that glucagon (50μg/Kg) produced a serious tachycardia in the dogs. The purpose of this study was done to determine the adequate method and dose of glucagon administration for the treatment of hemodynamical disorders in acute myocardial infarction, cardiogenic shock. Material and Method Twenty-five mogorel dogs, weighing from 7 to 14Kg, were anesthetized with intravenous sodium pentobarbital (25/Kg). An intratracheal tube was inserted and ventilation was carried out by a piston type respilator with room air. The heart was exposed by 4th intercostal thoracotomy. Myocardial infarction was produced by serial ligations of branches of the left circumflex coronary artery until a drop in the femoral arterial systolic pressure between 60 and 70% of the initial value was observed. Four dogs were died of serious arrythmia and cardiogenic shock soon after the ligation of the coronary artery and were rejected. Thirty minutes after the ligation of the coronary artery, glucagon (10μg/Kg) was administered intravenously as one shot over a two minute period in 5 dogs and glucagon (3-5 μg/Kg) in 6 dogs, and a continuous intravenous infusion in dosis of 0.5 μg/Kg/min was continued for I hours in 5 dogs. Heart rate, femoral arterial pressure, central venous pressure, cardiac output and left ventricular dp/dt were recorded with multipurpose polygraph (RM-150, Nihonkoden) before and 30 minutes after ligation of the coronary artery, and then 10 and 60 minutes after glucagon administration. Cardiac index (ml/Kg), stroke index (ml/Kg), left ventricular work and total peripheral vascular resistance were calculated.

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