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Giuseppe FERRO, Bruno RICCIARDELLI, Luigi SACCÁ, Massimo CHIARI ...
1980 Volume 21 Issue 6 Pages
765-771
Published: 1980
Released on J-STAGE: December 09, 2008
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Systolic time intervals (STI) are regarded as good indices of cardiac performance in many heart diseases. It must be considered, however, that they are temporally related to the cardiac contraction cycle and, therefore, may be modified by heart rate changes. Thus, it is necessary to define the possible relationship between STI and heart rate changes. In this study, changes in heart rate were induced by atrial and ventricular pacing. Tachycardia caused a proportional decrease of left ventricular ejection time (LVET) (y=275.142-1.0025x, r=0.76, p<0.001 for atrial pacing and y=298.28-0.691x, r=-0.75, p<0.001 for ventricular pacing, respectively), but did not modify the pre-ejection period (PEP) and the isometric contraction time (ICT) and the electromechanical interval (QS
1).
These results demonstrate that while LVET must be corrected for the changes in heart rate, no correction of PEP and ICT is necessary.
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Rajat K. MAHAPATRA, Jai B. AGARWAL, Prem CHOPRA
1980 Volume 21 Issue 6 Pages
773-777
Published: 1980
Released on J-STAGE: December 09, 2008
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The results of 62 autopsies of patients with rheumatic heart disease have been analyzed. The patients were 14-56 years old (mean 26 years). Thirteen patients had evidence of systemic thromboembolism (STE). All 13 patients had renal infarction, 2 had cerebral infarction, and 1 had a splenic infarction. Only 1 case with cerebral infarct was diagnosed clinically. Seven of 30 patients with atrial fibrillation had STE as did 6 of 32 patients with sinus rhythm. The type of valve involved and previous commissurotomy did not positively correlate with STE. It was observed that in this selected group of chronically ill patients who were autopsied, the elderly male patients with atrial fibrillation demonstrated increased incidence of STE.
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Takeo SAKURAI, Hideaki HOSHINO, Yoshio SUZUKI, Hideki YOKOI, Kozo SAKA ...
1980 Volume 21 Issue 6 Pages
779-792
Published: 1980
Released on J-STAGE: December 09, 2008
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Since 1973, the balloon catheter test with a Swan-Ganz, DotterLukas or Fogarty catheter has been attempted in our department in cases of atrial septal defect (ASD) and patent ductus arteriosus (PDA) during cardiac catheterization and operation.
Accurate informations concerning size, number and location of ASD were obtained during cardiac catheterization studies by using the balloon catheter. The difference between the size of the defect measured at catheterization and at operation was less than 1mm in diameter. Size of the defect ranged from 13 to 44mm in diameter (25.7mm on the average) and became larger with patient's age. Measurement of left-to-right shunt ratios before and after the temporary balloon occlusion of the defect was of help in making a preoperative diagnosis of ASD with multiple defects. Size of foramen ovale ranged from 3 to 13mm in diameter (5.2mm on the average) and was not related to age.
Size of the ductus in cases with PDA was measured during cardiac catheterization by using the balloon catheter. The difference between the size of the ductus measured with the balloon technique at catheterization and with a measuring rule at operation was less than 4mm in diameter. The difference revealed the extensibility of the ductus. The temporary balloon occlusion of the ductus aided in determining presence of other cardiac anomalies. In cases of isolated PDA, the murmur became inaudible with the occlusion of the ductus.
A balloon catheter inflated with radiopaque dye was used for measurements at cardiac catheterization and at operation. Persistent arrhythmias or other adverse effects of this procedure were not observed.
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Yutaka IMAI, Keishi ABE, Yoichi OTSUKA, Yutaka SAKURAI, Toru ITO, Maki ...
1980 Volume 21 Issue 6 Pages
793-802
Published: 1980
Released on J-STAGE: December 09, 2008
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Captopril (SQ 14225), an orally active converting enzyme inhibitor, was administered in a dose of 50mg to 12 normotensive subjects (Group I), 26 essential hypertensive patients (Group II), and 8 renovascular hypertensive patients (Group III). In Group III, 5 of the 8 patients had control plasma renin activity (PRA) similar to those in Groups I and II patients, but the PRA response to the administration of captopril was greater in 7 of the 8 patients than those in Groups I and II. These 7 patients had either bilateral or unilateral main renal artery stenosis. Captopril caused no increase in PRA in the remaining 1 who had unilateral renal artery stenosis with contralateral renal aplasia.
It is concluded that this provocation test is useful as a screening procedure for the diagnosis of renovascular hypertension.
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Seiya TSUCHIYA, Kouichi OGAWA, Tatsuo SATAKE
1980 Volume 21 Issue 6 Pages
803-815
Published: 1980
Released on J-STAGE: December 09, 2008
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We studied plasma levels of cyclic nucleotides and their responses to submaximal exercise as an endogenous adrenergic stimulation in normal subjects, untreated and treated patients with essential hypertension to assess the roles of various hormones and the autonomic nervous system in essential hypertension.
Plasma c-AMP level was significantly higher in untreated, diuretic-treated patients and those treated with propranolol than in normal subjects, but plasma c-GMP level was comparable in normal subjects and untreated patients. Plasma c-AMP decreased significantly, whereas plasma c-GMP increased significantly, after chronic propranolol therapy. Plasma c-AMP increased significantly after submaximal exercise in normal subjects, untreated patients and those treated with propranolol, but plasma c-GMP increased significantly only in normal subjects. The increase in plasma c-AMP was significantly higher in untreated patients than in normal subjects and patients treated with propranolol. Moreover, the percent increase in plasma c-AMP was significantly higher in untreated patients than in those treated with propranolol.
Therefore, it is suggested that the sympathetic nervous system may be hyperactive, and that a hyperreactivity of the β-adrenergic receptors may play an important role in essential hypertension.
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Lower Digoxin Concentration in Myocardial Microsornal Fraction in Infant Rats
Kazuto SAITO, Hiromitsu TANAKA, Tomoyoshi KASHIMA, Nobuyuki TANAKA
1980 Volume 21 Issue 6 Pages
817-825
Published: 1980
Released on J-STAGE: December 09, 2008
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To clarify the mechanism responsible for age-related differences in tolerance to digitalis, we studied the potassium contents of serum and myocardium and the digoxin concentrations of serum, myocardium, and myocardial microsomal fraction in infant and adult rats. While serum potassium concentration was the same in both infant and adult rats, the potassium content of myocardium found in the infant rats was significantly higher than that in the adult ones. Digoxin concentration of serum in infant rats was lower than that in the adult ones after a bolus injection of the same dose of digoxin per kilogram of body weight was given. Digoxin concentration of microsomal fraction, obtained 1 hour after the administration of 0.2mg/Kg of digoxin in infant rats, was lower than that obtained 1 hour after the administration of 0.1mg/Kg of digoxin in adult ones even though the digoxin concentrations of serum and myocardium in infant rats were significantly higher than those obtained in adult ones. Thus, less sensitivity to digitalis found in infant rats may be attributable to the higher potassium content of myocardium and the lower digoxin concentration of microsomal fraction.
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Hideharu HAYASHI, Hiromi SASSA, Midori OBA, Tetsuaki FUKAYA, Mitsuru O ...
1980 Volume 21 Issue 6 Pages
827-836
Published: 1980
Released on J-STAGE: December 09, 2008
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The acute hemodynamic effects of oral prazosin were investigated in 7 patients with chronic refractory heart failure. A single dose of 1 to 3mg prazosin produced a significant increase in cardiac index (+17.6%, p<0.01) associated with substantial decreases in pulmonary arterial diastolic pressure (-31.6%, p<0.02), systemic vascular resistance (-29.7%, p<0.01), and double product (-24.1%, p<0.02). Plasma renin activity was significantly elevated (+42.4%, p<0.02). These effects were found maximum at 2 hours and persisted for 8 hours.
The chronic hemodynamic effects in 5 patients with chronic refractory heart failure were evaluated by administration of 1 to 2mg prazosin 3 times daily for 8 weeks, and ventricular function was assessed by echocardiography and carotid pulse recording. All the patients showed improvement in the clinical symptoms of heart failure. Peripheral venous pressure decreased slightly (-12.5%). ET/PEP increased (+24.5%) without any significant changes in EF and mVcf. Plasma renin activity also slightly increased (+17.8%).
Thus, prazosin possesses sustained nitroprusside-like actions, and is effective in the management of chronic congestive heart failure refractory to conventional therapy. While, further investigation is necessary to define the effect of prazosin on plasma renin activity.
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Yasuyuki FURUKAWA, Miyoharu KOBAYASHI, Shigetoshi CHIBA
1980 Volume 21 Issue 6 Pages
837-844
Published: 1980
Released on J-STAGE: December 09, 2008
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Effects of temperature for inducing cardiac arrest by cooling and the reactivation by rewarming were investigated in the spontaneously beating canine atrium. Moreover, effects of temperature on paced atria and ventricles were also studied. By cooling, atrial rate was linealy decreased from 111 beats/min and then sinus arrest occurred at 20±0.3°C (mean±SE). Just before the arrest, sinus rate was 29±2.7 beats/min in 6 atrial preparations. On the other hand, atrial contraction was rather increased until about 25°C and then slightly decreased by cooling. In paced preparations, contraction of the atrium and ventricle initially increased and then decreased with pulsus alternans below the control level by cooling. Finally, pacing failure usually occurred.
When the reactivation was induced by rewarming after atrial arrest, atrial rhythm was suddenly recovered at about 25°C, but the contraction was minimum and gradually recovered to the control level.
From these results, it is suggested that atrial arrest by cooling may be due to sinoatrial conduction block and that the sinoatrial junction area may have an important role on the reactivation by rewarming. Moreover, the recovery of contraction by rewarming may be affected by several factors which may depress the tension development.
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Takeshi OTORII, Yumi KATANO, Keisuke TAKEDA, Shoichi IMAI
1980 Volume 21 Issue 6 Pages
845-857
Published: 1980
Released on J-STAGE: December 09, 2008
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Piridoxilate is a conjugation product of pyridoxine and glyoxylic acid, which may be a physiological regulator of cell respiration. Effects of this substance on the oxidation-reduction state of the pyridine nucleotides in the heart were studied using the canine heart-lung preparation supported by a donor dog. The oxidation-reduction state of the heart was estimated using the following 2 parameters: 1) myocardial redox potential and 2) NADH fluorescence in the heart muscle.
In doses above 0.4mM, piridoxilate produced a marked shift to more positive values of the myocardial redox potential and a decrease in NADH fluorescence. In contrast, ventilation of the animal with N
2 gas and infusion of NaCN into the preparation resulted in a shift to more negative values of myocardial redox potential and an increase in NADH fluorescence of the heart muscle. After pretreament of the preparation with piridoxilate, the depression of redox potential and the increase in NADH fluorescence produced by N2 gas inhalation or by NaCN infusion were clearly reduced. These findings suggest a protective action of piridoxilate against hypoxia which may be attributable to rearrangement of the myocardial metabolism.
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With Special Reference to Calcium Ion
Youichi TAKEYAMA, Koh OZAWA, Takashi KATAGIRI
1980 Volume 21 Issue 6 Pages
859-872
Published: 1980
Released on J-STAGE: December 09, 2008
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1. Alterations in subcellular distribution of electrolytes were studied with particular emphasis on Ca
++ in normal and ischemic myocardium produced by ligating the coronary artery in the dog, by means of the histochemical method using potassium pyroantimonate.
2. In the normal myocardium, the antimonate precipitates were observed most abundantly in TC of SR and on N-line within sarcomeric I-band, but found scarcely in mitochondria, M-line, Z-line, intercalated disc or T-system.
3. In the infarcted myocardium, the precipitates were strikingly increased in both number and size in disrupted mitochondria, while they were markedly decreased in swollen TC with the progress of ischemia.
4. Most of the precipitates in TC and on N-line were removed by chelation with EGTA but a few larger precipitates were consistently found mainly on N-line. And the presence of Ca
++ in the antimonate precipitates was confirmed by energy dispersive X-ray microanalysis.
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Yasuyuki FURUKAWA, Miyoharu KOBAYASHI, Shigetoshi CHIBA
1980 Volume 21 Issue 6 Pages
873-882
Published: 1980
Released on J-STAGE: December 09, 2008
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Electrical stimulation on the posterior portion in the caval margin of the right atrium caused a biphasic chronotropic and inotropic response, i.e., a negative response followed by a positive response, in the isolated blood-perfused canine atrial preparation. The threshold of pulse duration for inducing negative responses was approximately 0.05msec at 2v and 20Hz, but that for inducing positive responses was approximately 0.5msec. When the voltage and pulse duration of electrical stimulation were increased, both the degree of negative and positive responses became greater. However, muscle contracture was frequently induced by increasing the voltage or pulse duration. The optimal frequency was 20 to 40Hz for inducing marked chronotropic and inotropic responses.
The negative chronotropic and inotropic response to subthreshold electrical stimulation was significantly suppressed by the treatment with tetrodotoxin, hexamethonium or atropine, while it was enhanced by physostigmine treatment. These suggest that subthreshold electrical stimulation readily caused a release of acetylcholine by excitation of parasympathetic preganglionic fibers in this atrial preparation.
The positive chronotropic and inotropic response was significantly suppressed not only by treatment with propranolol but also by tetrodotoxin, while it was enhanced by imipramine, hexamethonium, or atropine.
From these results, it is indicated that this blood-perfused preparation is very suitable to evaluate both cardiac mechanisms controlled by autonomic nervous system and drug actions on effects of endogenous hormone.
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A Case Report
Massoud S. ALIPOUR, Ghodssi SHADKHOO, Cyavoush TARBIAT
1980 Volume 21 Issue 6 Pages
883-890
Published: 1980
Released on J-STAGE: December 09, 2008
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Clinical, hemodynamic, angiographic, and echocardiographic as well as operative findings of a 19 years old girl are presented who had the unique combination of severe pulmonary valvular and infundibular stenosis with Ebstein's anomaly of the tricuspid valve. Pulmonary stenosis was relieved by infundibular resection and valvotomy. The atrial septal defect was closed with plication of atrialized ventricle and insertion of a porcine tricuspid prosthesis. Recatheterization 2 months postoperativery revealed disappearance of characterestic angiographic findings and slight residual gradient.
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Yasushi KOIWAYA, Yasuhiko ORITA, Motoomi NAKAMURA, Tsuneo HIRATA
1980 Volume 21 Issue 6 Pages
891-896
Published: 1980
Released on J-STAGE: December 09, 2008
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Echocardiographic studies of a 23-year-old man with Ebstein's anomaly and type B Wolff-Parkinson-White syndrome showed almost simultaneous closure of the tricuspid and mitral valve. After administration of edrophonium chloride, the tricuspid valve closed 20msec earlier than the mitral valve. However, the closure of the mitral valve preceded that of the tricuspid valve after administration of ajmaline and atropine sulfate by 90msec and 60msec, respectively, concomitant with obliteration of preexcitation. From these observations, the simultaneous closure of the tricuspid and mitral valve of this case appears to depend on the preexcitation of the right ventricle.
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A Case Report
Kenji NAKAMURA, Shin SUZUKI, Shigeru SAKAKIBARA, Yukio KOMATSU, Sanae ...
1980 Volume 21 Issue 6 Pages
897-902
Published: 1980
Released on J-STAGE: December 09, 2008
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In a patient with patent ductus arteriosus, a pulmonary regurgitant murmur developed after the treatment of endocarditis. M-mode echocardiograms showed abnormal echo mass, characterized by fine diastolic fluttering, in the right ventricular outflow tract during diastole which were continuous with anterior pulmonary leaflet and thick pedunculated lesions attached to the anterior pulmonary leaflet were seen to be moving freely by cross-sectional echocardiography. At autopsy the destruction of the pulmonary valve was confirmed.
This study suggests that diagnosis of flail pulmonary valve is feasible by M-mode and cross-sectional echocardiography.
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Clinical, Echocardiographic, Angiographic, and Pathological Features
Kensuke HARADA, Ichiro SEKI, Hiroshi KOBAYASHI, Masahiko OKUNI, Isamu ...
1980 Volume 21 Issue 6 Pages
903-910
Published: 1980
Released on J-STAGE: December 09, 2008
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A 7-year-old boy presented with intermittent systolic murmur and syncope. Chest roentgenogram revealed mild cardiomegaly. Electrocardiogram showed right bundle branch block and abnormal T-waves. Right ventricular angiography demonstrated a filling defect at the anterior portion of the right ventricular cavity and histological examination of biopsy specimen revealed lipoma. At operation, the tumor could not be totally resected. Histological examination of surgical specimen showed marked proliferation of mature fat cells between cardiac muscle fibers. Postoperatively he has been remained asymptomatic. Postoperative standard M-mode and two-dimensional echocardiogram demonstrated a mass from right ventricular wall, abnormal motion of the interventricular septum and small left atrial cavity. The patient has been followed by serial echocardiography.
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