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Biomedical subjects

K Hirosawa

Publications and source records attributed to K Hirosawa.

At least 181 records · Page 10Linked to original sources

[Reliability and limitation of various diagnostic methods including nuclear medicine in myocardial disease (author's transl)].

Electrocardiography (ECG), echocardiography, nuclear method, cardiac catheterization, left ventriculography (LVG) and endomyocardial biopsy (biopsy) were performed in 40 cases of cardiomyopathy (CM), 9 of endocardial fibroelastosis (EFE) and 19 of specific heart muscle disease (SHMD), and the usefulness and limitation of each method was comparatively estimated. In CM, various methods including biopsy were performed. The 40 patients were classified into 3 groups, i.e., 1) hypertrophic (17), 2) dilated (20) and 3) non-hypertrophic . non-dilated (3) on the basis of left ventricular ejection fraction (LVEF) and hypertrophy of the ventricular wall assessed by LVG and/or echocardiography. The hypertrophic group was divided into 4 subgroups: 9 septal, 4 apical, 2 posterior and 2 anterior. M-mode scan was useful for detecting hypertrophy at the site of the ventricular septum and posterior wall, but not at the site of the anterior wall and apex. The hypertrophy was detected in 18 out of 20 cases using nuclear method. The posterior wall was hypertrophic but the septum was normal in 2 cases. In 2 of 3 non-hypertrophic . non-dilated cases, the left ventricle was oval in shape by LVG, echocardiography was normal, but significant pathological changes were seen in the biopsy, and there were abnormal ECG findings. There was no correlation between the ECG findings and the site of ventricular hypertrophy. Left ventricular ejection fraction measured by LVG (Kasser) had a closer correlation to LVEF obtained by nuclear method (multigated blood pool scan; r = 0.97) than LVEF by echocardiography (Teichholz; r = 0.79), although LVEF obtained by nuclear method was slightly higher than LVEF obtained by LVG. Myocardial perfusion defect was found in 10 of 20 cases of dilated cardiomyopathy (DCM) and the site of relative hypokinesis coincided with the site of the defect in 6 of 7 cases. A semi-quantitative myocardial perfusion defect index (PDI) and histo pathological contractility failure index (HCFI) obtained by the biopsy were devised. HCFI is the score of myocardial degeneration, fragmentation and fibrosis. The PDI plus HCFI had a close correlation with LVEF (r = -0.898). In 9 cases of DCM, LVEF was more reduced than right ventricular ejection fraction. The perfusion defect was also found in 4 cases of EFE and 4 cases of SHMD, i.e., sarcoidosis, postmyocarditis, Kugelberg-Welander disease and cardiac tumor. We conclude that the nuclear study is useful in assessing the site of the abnormal ventricular thickening, perfusion defect and ventricular function. Echocardiography is most useful in detecting ASH. The biopsy gives the sole diagnostic clue, especially in non-hypertrophic . non-dilated cardiomyopathy. ECG is useful in all cases but correlation with the site of disproportional hypertrophy was not obtained.

Adolescent↗

[Two-dimensional echocardiographic and RI angiographic features of aneurysm of the ascending aorta in patients with annuloaortic ectasia (author's transl)].

The purpose of this study was to compare the diagnostic value of two-dimensional echocardiography with that of other methods in the detection and localization of aneurysm involving the ascending aorta in patients with annuloaortic ectasia. Two-dimensional echocardiography, RI angiography, CT scan and aortography were performed in 19 patients (12 patients with Marfan's syndrome, 4 with aortitis syndrome and 3 with postoperative perivalvular aneurysm). Eight of 12 patients with Marfan's syndrome had dissection in the ascending aorta which was confirmed at surgery or autopsy. The following observations were obtained. 1) Dissection of the ascending aorta was clearly demonstrated on the two-dimensional echocardiogram in 7 patients by recording the intimal tear and flap, and in these cases the short axis two-dimensional echocardiogram of the ascending aorta was more useful in identifying the site and extent of dissection. 2) In patients with postoperative perivalvular aneurysms, RI angiography proved to be a more useful and sensitive technique in differentiating a leakage into the aneurysm from clots in the aneurysm. 3) CT scanning proved to be an insensitive technique to detect dissection of the ascending aneurysm and to differentiate a leakage from clots in the perivalvular aneurysm. From these observations, we concluded that two-dimensional echocardiography and RI angiography proved to be sensitive techniques in detecting dissection of the ascending aneurysm and evaluating a postoperative aneurysm in patients with annuloaortic ectasia.

Aortic Dissection↗

[The diagnosis of left atrial thrombi by selective coronary arteriogram and two-dimensional echocardiogram (author's transl)].

In 14 patients with left atrial thrombi, coronary arteriography and real time, two-dimensional echocardiography were performed and compared with the surgical findings. Age of the patients with left atrial thrombi was relatively high, and their hemodynamic findings were severe. By the combined use of coronary arteriography and real time two-dimensional echocardiography, the prediction of left atrial thrombi was possible in 93%. Coronary arteriography provided a useful information as to the location of thrombi, especially in the left atrial appendage, while the size and shape of thrombi were not predictable by this method. On the contrary, two-dimensional echocardiography was useful to determine the size and shape of the thrombi.

Adult↗

[Aneurysm of sinus of Valsalva ruptured into the interventricular septum: a case report (author's transl)].

A 48-year-old male with a history of progressive atrioventricular conduction disturbance and a peculiar diastolic regurgitant murmur was reported. The echocardiographic examination and cineangiography disclosed an aneurysm of the right coronary sinus of Valsalva ruptured into the interventricular septum, which bulged into the left ventricular outflow tract in diastole and moved toward the septum in systole. The intracardiac phonocardiogram revealed that an unperforated sac in the interventricular septum, protruded into the left ventricular outflow tract, caused an unusual regurgitant murmur. The patient underwent successful surgical repair of the perforated orifice.

Aortic Rupture↗

Clinical and histopathological profile of sarcoidosis of the heart and acute idiopathic myocarditis. Concepts through a study employing endomyocardial biopsy. II. Myocarditis.

Through an approach employing endomyocardial biopsy, early diagnosis of acute idiopathic myocarditis is possible. The histopathological findings consisted of fragmentation of muscle bundles, degenerative changes with lysis of myocytes and interstitial mononuclear cell infiltration. The cells were irregular in size and shape and contained slightly basophilic cytoplasm or were mixed with small round cells. Early clinical symptoms consisted of flu-like symptoms, i. e., higher fever, myalgia, malaise and arthralgia. Initial ECG changes consisted of complete A-V block in 9, bifascicular block in 3, and intraventricular conduction disturbance in 4 cases. Serial biopsies were performed at the early (0--2 weeks), middle (2--4 weeks), and late stages (more than 4 weeks) in 6 cases. Two of these biopsies were performed in 6 cases and all 3 were performed in one case. The numerous interstitial cell infiltration had almost disappeared by the early stage. At the late stage, either a slight or moderate degree of interstitial fibrosis was observed. These observations coincided well with the improvement of the ECG findings. Characteristic laboratory findings consisted of high LDH, GOT, and serum amylase levels. Varieties of treatments such as temporary cardiac pacing, peritoneal or hemo-dialysis, vasodilator therapy effectively to relieve the grave clinical condition. It is concluded that acute myocarditis may heal with remarkable improvement when the appropriate treatment is applied at the early stage of the disease.

Acute Disease↗

M-mode and cross-sectional echocardiographic features of flail pulmonary valve. A case report.

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.

Adult↗

Electron microscopic observations on the pit organ of a crotaline snake Trimeresurus flavoviridis.

The pit membrane in the pit organ of a crotaline snake is about 15 micron thick. Myelinated nerve fibers from the trigeminal nerve enter the pit membrane and swell into palmate structures on demyelination. Demyelinated fibers repeat branchings and their terminals contain many mitochondria. The terminal portion is not surrounded with Schwann cell processes. There are many small vesicles (30-60 nm in diameter) in the extra-cellular space in close association with the nerve terminal membranes. The spreading of branches from each palm seemed to have a definite territory which would correspond to the unit area detected with electrophysiological methods. But no "unit structure" was revealed by electron microscopy. intraepithelial free nerve endings exist in the outer epithelial layer. The nerve bundles from the trigeminal branches contain some unmyelinated fibers which come in close contact with vascular elements in the pit membrane.

Animals↗