The characteristic ultrasono-cardiographic (UCG) findings of prolapsed mitral valve were studied in 9 cases by means of ultrasono-cardiotomography (UCT). The changes in degree and shape of the prolapsed valve were examined and the leaflet involved was identified.
Of the 9 cases, 5 had prolapse of anterior, 3 had that of posterior leaflet and 1 had both. In all cases with midsystolic click and late systolic murmur or pansystolic murmur with late systolic accentuation, the prolapse of anterior leaflet was observed on UCT, and though UCG disclosed midsystolic buckling it was difficult to determine the exact timing of the prolapse by UCG alone.In the cases with rheumatic mitral regurgitation, the prolapse of posterior leaflet and the ballooning of anterior leaflet could easily be found on UCT, but the detection of the above-mentioned 2 findings was difficult by UCG alone.
Three of the 9 cases were found to have prolapse of posterior leaflet by left ventriculography, whereas these 3 had prolapse of anterior leaflet on UCT. Hence, the diagnosis of prolapsed mitral valve based on the cineangiography may require re-evaluation.

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With the use of bidirectional echocardiography, the isometric contraction (ICT) and relaxation times (IRT) of both ventricles were measured in 14 normal subjects (N), 6 cases with right ventricular (RV) diastolic overloading (DO), and 5 cases with RV systolic overloading (SO). The RVDO group consisted of patients with atrial septal defect of ostium secundum type who had large left-to-right shunting, and the RVSO group those with pulmonary hypertension of various origins. The mean ICT and IRT in N were 28.5±4.8 and 43.8±1.7msec for RV, and 43.3±5.6 and 60.9±9.0msec for left ventricle (LV), respectively. The RVDO group showed no significant change in the mean ICT and IRT of RV (29.7±4.6 and 54.3±11.8msec, respectively), but significantly greater means of ICT and IRT of LV (58.5±9.5 and 83.6±14.1msec, respectively). In the RVSO group, the mean ICT and IRT were 51.0±4.1 and 86.8±8.2msec for RV, and 72.4±12.2 and 116.0±20.4msec for LV, respectively. These values were all significantly greater than the means for both N and RVDO groups, except that the mean ICT of LV was insignificantly different between the RVDO and RVSO groups. It was noted that the intervals of LV tended to increase with the increasing intervals of RV, suggesting the changes in LV function secondarily due to RV overloading. It was concluded that the measurement of ICT and IRT of both ventricles is of clinical value for evaluation of overall cardiac function in the patients with RV overloading.

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Sixty-four blood samples from 28 uremic patients were analyzed for total calcium (Ca), inorganic phosphate (P), total protein (TP), and albumin in the serum. In these patients Ca had no significant correlation with either TP or albumin as was generally postulated, but showed significant correlation only with P. The regression analysis revealed that the residuals were of the same order of magnitude in both linear and non-linear formulation.
It was also found that the product, Ca×P, increased along with BUN in uremic patients.

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The hemodynamic effects of a new adrenergic β-receptor blocking agent, Kö 1366 were investigated in normotensive and hypertensive elderly subjects. This study, in its important part, was carried out to clarify whether the intrinsic sympathomimetic activity of Kö 1366 modified the hemodynamic changes due to β-adrenergic blocking action or not. Hemodynamic changes elicited by intravenously administered Kö 1366 (0.05mg/Kg) were correlated with age, cardiac index, and electro-cardiographic findings, respectively.
With reference to age in normoteinsve subjects, Kö 1366 caused no significant differences in rate of changes of various hemodynamic items between 3 age groups. Normotensive elderly subjects were divided into 3 groups according to cardic index. Cardiac index decreased greatly in high cardiac index group, slightly in normal cardiac index group, whereas it increased greatly in low cardiac index group. Stroke volume index showed the same tendency as cardiac index. Hypertensive elderly subjects were, also divided into 2 groups according to cardiac index. Again, cardiac index decreased in higher cardiac index group, while it increased in lower cardiac index group, though a statistical evaluation showed only a tendency of significant difference be-tween 2 groups. In the next, hypertensive elderly subjects were divided into 2 groups according to electrocardiographic findings of left ventricular hypertrophy. Cardiac index decreased in the subjects without electro-cardiographic changes, while it increased in the subjects with electro-cardiographic changes. Stroke volume index of both groups increased: a greater increase in the subjects with electrocardiographic changes and a tendency of significant difference between 2 groups was recognized.
These results suggested that Kö 1366 exhibited the intrinsic symathomimetic activity on the inotropism in the hearts with depressed contractile function of both normotensive and hypertensive subjects, thereby canceling the negative chronotropic action of this agent. This could be a more advantageous point of Kö 1366 in the treatment of elderly subjects with cardiac diseases than other agents without the intrinsic sympathomimetic activity.

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The effects of Ca⁺⁺ and Mg⁺⁺ infusion on the cardiovascular system were studied in 96 normotensive subjects and 85 hypertensive patients.
The results obtained were as follows:
(1) The effects of Ca++ infusion on the systolic time intervals were characterized by the shortening of QS₂I, PEPI, and ICT, and increase in ET/PEP. The responses of the systemic hemodynamics were elevation of mean blood pressure and increase in cardiac index and stroke index. The heart rate was not altered.
(2) These results support that Ca++ has a positive inotropic action and increases the left ventricular performance.
(3) The effects of Mg⁺⁺ infusion on the systolic time intervals were characterized by the prolongation of QS₂I, PEPI, and ICT. The responses of systemic hemodynamics were elevation of mean blood pressure and increase in heart rate. The ET/PEP and cardiac index tended to decrease, but these changes were not significant.
(4) From these results it is suggested that Mg++ depresses myocardial contractility and has a positive chronotropic action.
(5) There were no significant differences in the systolic time intervals and hemodynamic responses to the infusion of Ca⁺⁺ and Mg⁺⁺ between normotensives and hypertensives.

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Grossly abnormal serum lipoprotein (Lp) profile which appeared as a broad-midband pattern (BMP) in PAG electrophoresis was detected in 67% of uremic patients maintained by prolonged hemodialysis therapy (hemodialysis patients). It was revealed that BMP was ascribed to the presence of a discrete series of Lps which were intermediate between β-migrating LDL and pre-β-migrating VLDL regarding buoyant density, S_f rate, chemical composition, and behavior in electrophoresis. The results in the present study indicate that the accumulation of these Lps, which may include the previously-known Lp species such as the intermediate-density Lp or the remnant particles, is taking place in hemodialysis patients.

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Noninvasive monitoring of patency of aorta-coronary bypass grafts can be achieved with reasonable accuracy using the thermocouple. This method is consisted of attaching the thermocouple to the surface of grafted vein during surgery and judging the patency by rapid injection of iced solution into peripheral vein. Patent grafted vein will show the thermal change after injecting iced solution. On the contrary, occluded graft will show no thermal change.
As this thermal curve is a thermodilution curve by a single injection and is measured from the outside of the vessel, thermal change depends on the temperature and the quantity of the injected solution, cardiac output, body temperature, and loss of indicator temperature along the way to the thermocouple. When the grafted vein is patent, the same thermal curves are recorded regardless of the amount of the flow, and zero flow resulted in disappearance of curve.
Initially, the method was evaluated in dogs and the appropriateness was verified. Subsequently, this method was applied to 16 vein grafts of 12 patients undergoing aorta-coronary bypass surgery. Ten or 15 ml of iced solution was injected through inferior vena cava or antecubital vein and the thermal change of the grafted vein was recorded for 1-4 weeks after the operation. Fourteen grafted veins were judged to be patent and 2 were occluded. The comparison of the results by this method with coronary angiography undergone at 4 weeks after the operation showed no false positive case but 1 false negative case.
This extravascular observation of the thermodilution curve is a convenient method for judging whether vein graft is patent or not.

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Effects of cardioactive substances on the post-stimulation potentiation of atrial contractility were studied in 17 isolated, blood-perfused preparations of dogs. Maximum degree of the post-stimulation potentiation was obtained over approximately 3.5Hz within 5-60 sec of stimulation. Each drug was administered directly into the cannulated sinus node artery of isolated atrium. An adequate dose of verapamil, manganese chloride, or pentobarbital which caused marked depression of contractility did not significantly suppress the post-stimulation potentiation in percent changes. The post-stimulation potentiation was not inhibited by continuous infusion of adenosine, which caused a negative inotropic effect. Tetrodotoxin, propranolol, or caffeine also never suppressed the post-stimulation potentiation but ouabain abolished it in the majority of cases.

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To investigate the hemodynamic aspects across a stenosis in the cardiovascular system, in vitro, in vivo, and clinical studies were performed. The results are summarized as follows:
1) Remarkable changes in the pressure profile were recognized downstream. The relationship between pressure gradient and flow across the stenotic orifice revealed an inverse linear relationship in in vitro studies, but showed a slight convex curve in in vivo studies.
2) The critical stenosis in in vitro and in vivo studies was 10% and 25%, respectively.
3) In the group of mitral valve area larger than 0.5cm², flow coefficient C was smaller than 1.0 and blood flow could be "vena contracta".
4) Gorlin's formula is considered to be appropriate in the cases with valve area larger than 0.5cm². But Gorlin's formula may over-estimate in the group with valve area smaller than 0.5cm².

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The effects of the agents that inhibited synthesis of prostaglandins (PGs) and thromboxanes (TXs) on cyclical reduction of blood flow in partially constricted coronary artery of anesthetized dog were examined.
The cyclical reduction of coronary blood flow was eliminated by intravenous injections of aspirin that inhibited synthesis of endoperoxides, of benzydamine that inhibited synthesis of endoperoxides and TX A₂, and of phenylbutazone that inhibited synthesis of PG E₂, but was not of reduced glutathione that inhibited synthesis of TX A₂ and accelerated synthesis of PG E₂. In the preparations in which cyclical reduction of blood flow did not occur spontaneously, intracoronary injection of PG E₂, but not of PG F_2α, induced the cyclical reduction. The cyclical reduction was also induced by intravenous injections of epinephrine and reduced glutathione that accelerated synthesis of PG E₂. The results indicate participation of PG E₂ in the cyclical reduction of coronary blood flow.

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Right atrium-femoral artery VAB without oxygenation was performed in 7 dogs at 3 different bypass ratios, 15%, 30%, and 45%. Respiration and cardiac output were controlled. Precise intra-aortic distributions of PO₂ and O₂ saturation were determined by means of a PO₂ catheter probe and an oxygen analyzer.
The following was concluded:
1) The blood pumped from dog heart produced a narrow "mixing zone" in the mid-aorta with the blood pumped from VAB. The area of the "mixing zone" was in the distal half between renal artery and bifurcation at 15% bypass ratio, in the proximal half between renal artery and bifurcation at 30% bypass ratio, and from celiac artery to below renal artery at 45% bypass ratio. It shifted proximally as the bypass ratio increased.
2) In order to supply necessary oxygen to abdominal viscera, it is recommended that the bypass flow should not exceed 30% of the baseline cardiac output.

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In a 42-year-old man with severe hypertension, stenosis of the left renal artery at its origin and occlusion of the abdominal aorta below the level of the renal arteries were observed. His past history and clinical and laboratory findings suggested that the renal artery stenosis was due to Buerger's disease which was reported to be a rare cause of renovascular hypertension.

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