Isoproterenol, epinephrine, and norepinephrine, intracoronarily injected with the coronary artery catheterization, produced a. marked "ischemic" change in ECG, while phenylephrine failed to do so. This change was inhibited by the pretreatment with propranolol, but not by that with phenoxybenzamine. No marked change was produced in the coronary blood flow by these catecholamines, but a change occurred in blood pressure pulse pattern recordable from the carotid artery in association with ECG changes. When the magnitude of the "ischemic" change in ECG produced by graded-dose administration of epinephrine was quantitated in terms of ST·T-Area, it was found that the change in ST·T-Area depended on the dose of epinephrine used; norepinephrine produced changes in ECG with nearly equal potency to epinephrine. ECG changes caused by epinephrine in dose of 1 μg was completely inhibited by the pretreatment with about 125 μg of DL-propranolol, L-propranolol or ICI 50172, but 400 μg of D-propranolol was required to produce the same blocking effect. On the other hand, procaine had no such inhibitory effect. From these results it is suggested that the epinephrine-induced ECG changes of "ischemic" type appear to represent a beta-adrenergic response. When the ST and T changes were quantitated in terms of ST·T-Area, propranolol exerted a blocking action on such epinephrine-induced ECG changes, and D-propranolol was one third as potent in this respect as L-propranolol.

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Phonocardiographic, hemodynamic and angiocardiographic study in thirty two patients with isolated aortic insufficiency or accompanied by other valvular lesions or congenital defects were carried out with special reference to the correlation between configuration of the diastolic murmur and regurgi-tant percent, and between Q-1 interval and end-diastolic volume of the left ventricle. 1. Regurgitant percent may be assumed as the 'most adequate index of the severity of aortic insufficiency. No correlation was found between regurgi-tant percent and diastolic pressure or pulse pressure of the aorta. 2. The interval between second heart sound and maximum amplitude of the diastolic murmur, and between the maximum amplitude and half of it correlated significantly with regurgitant percent, the former more significantly. 3. Q-1 interval was correlated with end-diastolic volume and electrical mechanical interval. Q-1 interval had no correlation with total ventricular activation time. Therefore, prolongation of the Q-1 interval in aortic insuffici-ency may be due to the prolongation of the electrical mechanical interval.

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Purpose: To elucidate the role of myocardial storage energy during exercise, the change of coronary arterio-sinus differences of inorganic and creatine were measured before and exercise loading. And the data were compared with coronary circulation, myocardial metabolism of oxygen and carbohydrates, to make clear the myocardial metabolism of phosphocreatine during exercise in patients with circulatory diseases. Methods and Materials: Coronary sinus catheterization and brachial artery needling were carried out. The samples of coronary sinus and artery were taken before and during exercise. The exercise was performed by bicycle ergometer at a level of 50 watts for 15 minutes. The inorganic phosphorus and creatine were measured by Fiske-Subbarow and Folin-Wumodification methods respectively. The patients studied were 4 patients with neurocirculatory asthenia (N.C.A.), 7 patients with hypertension without any sign of coronary insufficiency (H.T.), 9 patients with coronary insufficiency who had angina pectoris or ischemic ECG changes at rest or during exercise (C.H.D.) and 8 patients with the other cardiac diseases, for example valvaral diseases etc (H.D.). Results: A) Metabolism of inorganic phosphorus; 1) The arterial concentration of inorganic phosphorus in 28 patients at resting state was 3.17 ± 0.58 mg/dl on average. The arterial concentration of inorganic phosphorus was increased during exercise in 27 out of 28 patients, being 3.72 ± 0.57 mg/dl at mean value, and the increase was statistically significant. But there was no significant difference in arterial concentration of inorganic phosphorus among disease groups at rest and during exercise. 2) The coronary arterio-sinus difference of inorganic phosphorus was statistically significant in patients with N.C.A. and with H.D. at rest, but there was no significant difference in these values among disease groups. By exercise, the from 0.092 ± 0.028 mg/dl to 0.157 ± 0.076 mg/dl in N.C.A. and from 0.060 ± 0.070 mg/dl to 0.120 ± 0.082 mg/dl in H.T., but these changes were not significant. While in C.H.D. it decreased from 0.068 ± 0.102 mg/dl to -0.107 ± 0.149 mg/dl and in H.D. from 0.095 ± 0.101 mg/dl to -0.074 ± 0.058 mg/dl. This decrease was statistically significant.

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In the detection of shunt and regurgitation in cardiac diseases or in the measurement of cardiac output by dye dilution method, an intuitive interpretation of the shape of obtained curves is unavoidable. Therefore, 'the results obtained are not always accurate. Especially, the curves recorded through ear piece after injection of the dye into the peripheral veins are sometimes equivocal and less accurate than those obtained by injection of dye in the large central vessels, although the former procedure is much simple and does not inflict much discomfort to the patients. Accordingly, it would be very advantageous for us to develop a means for deriving the useful information sufficient for clinical diagnosis from the curves obtained by the former method. In this respect, the writer has developed a method, in which the dye dilution curves recorded through ear piece is measured automatically and the presence or absence of shunt or regurgitation is determined by a computer. Calculation of cardiac output is, of course, included in the procedure. The dye dilution curves, which were used for the present study, were recorded by the Cam-bridge's Dye Dilution Curve Recorder using an ear piece. The employed dye was Coomassie blue, 40 mg of which was injected into the antecubital vein. In recording the dye dilution curve, generally t_o, t_i, t_p, t_L, t_r, t_d, c_p, c_t, c_r and the terminal concentration (E_t) have 'been measured hitherto. In writer's experience, however, the ascending and descending limbs also show outstanding characteristic in some of the diseases. Accordingly, the maximum slope of the ascending limb (maxS₁) and its average slope (meanS₁) during the period of 3 sec. (1.5 sec. before and 1.5 sec. after the point of the maximum slope), the maximum slope of the descending limb (maxS₂) and its average slope (meanS₂) were added to measuring items. When shunt or regurgitation exists, the calculation of t_d becomes inaccurate, so that the point (t_d, ) where meanS₂ intersects the baseline was used in place of t_d, A ratio of C_p/E_t was also added. Thus, a total of 19 items were used. The dye dilution curve was digitized by A-D converter at a sampling rate of 6 per second. The curves, which had been recorded on the sheets previously, were put in the tape recorder using a pencil follower, then delivered also to an A-D converter.

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