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Biomedical subjects

Y Nimura

Publications and source records attributed to Y Nimura.

At least 181 records · Page 10Linked to original sources
PubMed1985

Doppler echocardiographic features of ventricular septal rupture in myocardial infarction.

Doppler echocardiography was used to evaluate the features of interventricular septal rupture in six patients with acute myocardial infarction and to substantiate the hemodynamic data and morphologic findings at surgery or autopsy. Although echocardiographic visualization of the septal rupture was obtained in only two of the six patients, unusual Doppler flow signals were detected in the apical portion of the right ventricle in all six patients. Five patients had unusual flow signals during both systole and diastole; one had such signals only during systole. The location of these unusual flow signals coincided with the site of septal rupture confirmed at surgery or autopsy. The pattern of the flow signals in one cardiac cycle was very similar to that of the pressure difference between the left and right ventricular cavities. These findings indicate that the unusual flow signals represent the left to right shunt flows resulting from septal rupture. In conclusion, Doppler echocardiography may be a very useful tool for diagnosing interventricular septal rupture easily and noninvasively in patients with acute myocardial infarction.

Aged↗
PubMed1985

Smoke-like echo in the left atrial cavity in mitral valve disease: its features and significance.

In some patients with mitral stenosis, a smoke-like echo is observed in the left atrial cavity. The present study in 116 consecutive patients with rheumatic mitral valve disease investigated the echocardiographic features and clinical significance of this echo. The smoke-like echo is characterized by the following echocardiographic features: 1) it is composed of numerous microechoes; 2) it curls up slowly in the enlarged left atrial cavity; and 3) it vanishes as soon as it pours into the ventricular cavity. Hemostasis in the left atrial cavity was considered to be an important underlying condition for development of the echo. Hemorheologic conditions indicated that the shear rate of blood flow in the left atrial cavity was calculated to be low enough for the development of red blood cell aggregation. These conditions suggest that the source of the smoke-like echo might be aggregated cells due to hemostasis in the left atrial cavity. Left atrial thrombi were detected in many patients who had this echo in the left atrial cavity. Although it has not been conclusively determined that the presence of the smoke-like echo is a necessary condition for thrombus formation, this echo appears to be closely related to thrombus formation in the left atrial cavity. It is concluded that the presence of this echo indicates severe left atrial hemostasis and is a warning for thrombus formation.

Adult↗
PubMed1985

Recent progress in ultrasonic diagnosis of the heart: Doppler flow imaging.

It is appreciated that, linked with B-mode echocardiography, the real-time two-dimensional Doppler flow imaging technique provides information on the heart, which has never been available with conventional methods, greatly improving the capabilities of cardiac ultrasound. In general, the concept of major heart disease consists of anatomical abnormalities and those in intracardiac flow condition. The present method provides information on these two aspects simultaneously; consequently, it is regarded as a closer approach to heart diseases, compared with conventional examinations and techniques. The equipment is also convenient to operate. The combination of real-time two-dimensional Doppler flow imaging and B-mode echocardiography is expected to become a standard tool of the ultrasound examination of the heart.

Aortic Valve Insufficiency↗
PubMed1985

[Palliative treatment for unresectable cases of pancreatic carcinoma].

Palliative treatment have been performed in 50 cases of unresectable pancreatic carcinoma during these nine years. There were 36 in the head and 14 in the body and tail on the location of the tumor. Operation was performed in 35 cases (70%) and about 60% of which were diagnosed as unresectable for liver metastases. Prophylactic gastroenterostomy concomitant with biliary bypass is considered to be the most suitable procedure and should be performed routinely regardless of duodenal obstruction. Choledochojejunostomy (Roux-en-Y) and gastrectomy (Billorth-II) were considered advantageous for favorable long-term bile drainage and to prevent hematemesis. Splanchnicetomy proved to alleviate pain in 87.5% and is recommended to perform at the time of initial laparotomy. Postoperative adjuvant chemotherapy was performed in 40% of the cases. Arterial infusion chemotherapy was found most effective to prolong survival. The patients who received palliative treatment survived 6.5 months on the average: Mean survival was 7.3 months in the former cases and 3.8 in the latter. Six patients (12%) survived more then one year, and no significant difference in location or size could be found.

Adult↗
PubMed1985

[A case of membranous obstruction of inferior vena cava at the hepatic associated with hepatocellular carcinoma and liver cirrhosis].

A case of inferior vena cava obstruction at the hepatic portion associated hepatocellular carcinoma with and liver cirrhosis is reported, which was treated with lateral segmentectomy of the liver after transcatheter angioplasty. A 36-year-old male, who had noticed venous dilatation in the abdominal wall and legs from his childhood, visited a doctor complaining of right upper quadrate pain and was diagnosed liver cirrhosis. One year later ultrasonography revealed a liver tumor, which was diagnosed as hepatocellular carcinoma by ultrasonically guided aspiration cytology. Inferior and superior vena cavography revealed complete membranous obstruction of inferior vena cava at the hepatic portion with marked collateral circulation through azygos, hemiazygos and phrenic veins. The caval pressure difference between above and below the obstruction was 16.5 cm H2O. The membranous obstruction was perforated and dilated by transluminal angioplasty using Dotter's balloon catheter. The obstructive segment of inferior vena cava changed into 8mm in diameter after the second angioplasty, and the caval pressure difference between above and below the stenosis decreased to 10 cm H2O. Lateral segmentectomy of the liver was performed. Histopathologic diagnosis was clear cell type hepatocellular carcinoma with liver cirrhosis. Marked postoperative liver damage was observed and transcatheter caval dilatation was performed again. The pressure of inferior vena cava below the stenosis decreased to 8 cm H2O. One year and 8 months after the operation, the patient is healthy without recurrence of cancer.

Adult↗
PubMed1985

[Clinicopathological studies on pancreatic carcinoma in totally pancreatectomized cases--with special reference to its intrapancreatic development and the pancreatogram].

Histological examination and pancreatography were performed on 31 totally pancreatectomized cases of pancreatic ductal carcinoma, which was divided into four types according to its growth pattern in the pancreas. Pancreatograms of the resected specimens were also classified according to histological findings. Pancreatic carcinoma of Type I (20 cases) was diffusely infiltrating carcinoma with scirrhous stroma which was particularly present between the lobules. The pancreatogram of this type showed constriction of the main pancreatic duct accompanied by dilatation of the distal pancreatic duct. Carcinoma of Type II (6 cases) was diffusely developing in or around the dilated main pancreatic duct or its branches. The pancreatogram of Type II demonstrated the irregularly dilated main pancreatic duct with absence of its branches. Type III (4 cases) was the localized carcinoma with medullary structure. The pancreatogram showed replacement and dilatation of pancreatic ducts without marked stenosis of the main pancreatic duct. Type IV (1 case) was intraductal protruding carcinoma which showed polypoid shadow defects in remarkably dilated pancreatic ducts. The results suggested that a total pancreatectomy should be applied mainly for pancreatic carcinomas of Type II.

Adenocarcinoma↗
PubMed1985

[Mitral regurgitation: detection and quantitative evaluation by two-dimensional Doppler echocardiography].

Mitral regurgitation was detected and quantitatively evaluated using two-dimensional Doppler-echocardiography. The subjects consisted of 74 cases having a variety of heart diseases, who underwent left ventriculography within one week before or after the Doppler study. Among 50 patients with mitral regurgitation confirmed by left ventriculography, the Doppler study detected mitral regurgitant flow signals in 46, for a sensitivity of 92%. Minimal mitral regurgitation in four cases could not be detected by Doppler studies. Twenty-four patients had no mitral regurgitation according to left ventriculography; all but one also had no mitral regurgitation by Doppler study, for a specificity of 96%. In one false positive case, typical mitral regurgitant flow signals were detected in an area localized within the left atrial cavity near the mitral valve orifice. The possibility remains that left ventriculography missed this minimal regurgitation. For quantitative assessment of mitral regurgitation, the following two methods were used. Three long-axis views through the lateral, middle and medial parts of the mitral valve, and a short-axis view at the level of the mitral orifice were imaged via the parasternal approach. The area where mitral regurgitant flow signals were detected was mapped on each cross-sectional echocardiogram, then the distance attained by the regurgitant flow from the mitral valve and the area covered by the regurgitant flow were determined. The maximal distance among the three long-axis views and the sum of the distances in these views was parallel to the severity of mitral regurgitation as assessed by left ventriculography.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1985

[A case of resected renal cell carcinoma with massive pancreatic metastases].

A case of resected renal cell carcinoma with massive pancreatic metastases is reported. A 72-year-old man was diagnosed as suffering from obstructive jaundice. Massive pancreatic tumor and left renal tumor were shown by several kinds of radiological examination. Total pancreatectomy and left nephrectomy were performed. Postoperatively this case was histologically diagnosed as renal cell carcinoma with massive pancreatic metastases. Very few cases of resected renal cell carcinoma with pancreatic metastasis have been reported in the world. In such cases, there is no useful treatment except for resection of both the primary and metastatic lesions.

Aged↗
PubMed1984

Clinical applications of a new type of real-time two-dimensional Doppler flow imaging system.

The clinical significance of a newly developed real-time 2-dimensional (2-D) Doppler flow imaging technique was assessed. In the instrumentation of the echocardiograph, the pulsed Doppler mechanism was incorporated in a wide-angle, phased-array system. The Doppler flow signals obtained from the cardiac chamber were processed on the basis of the autocorrelation principle. The direction, velocity and variance of the intracardiac blood flow were calculated in real time and displayed in the color-coded mode on the television screen, and were superimposed on the 2-D echocardiographic image of the heart. The technique was used in 20 healthy subjects and 100 cardiac patients. The new technique clearly visualized the whole aspect of intracardiac blood flow by the cine mode in real time; thus, the technique may be called Doppler cineangiocardiography. The mitral inflow and the aortic ejection flow were clearly demonstrated. A regurgitant jet from the valve orifices was dynamically visualized as seen in the cineangiogram. The spatial orientation and extent of the regurgitant jet were easily assessed. The jet stream through the stenotic mitral orifice was well imaged in the left ventricular cavity, showing a variety of stream directions. Intracardiac shunts in ventricular septal defect and atrial septal defect were clearly visualized. The defect could be localized on the interventricular septum on the basis of the site where the shunt flow spurted, although the echocardiographic interruption was not demonstrated in the 2-D echocardiographic image of the cardiac structure. Although some technical problems remain, our new technique greatly improves the diagnostic efficacy of ultrasound.

Adolescent↗
PubMed1984

Augmentation of atrial contribution to left ventricular inflow with aging as assessed by intracardiac Doppler flowmetry.

The influence of aging on the left ventricular (LV) function in diastole was investigated from the aspect of the mitral inflow pattern using 2-dimensional Doppler echocardiography. The subjects for the investigation were 69 persons who were diagnosed as healthy by a checkup examination. The peak velocity in the rapid filling phase and that in the atrial contraction phase tended to decrease and to increase with aging, respectively. However, these tendencies were not statistically significant. However, the ratio of the atrial contraction phase to the rapid filling phase showed a significant increase with aging (r = 0.82, p less than 0.001). Therefore, it is considered that the mitral flow conditions are influenced by aging. The result obtained is also interpreted to mean that the LV distensibility in early diastole is impaired with aging and that the contribution of the atrial contraction to LV filling is compensatorily augmented.

Adult↗
PubMed1984

3-(p-hydroxyphenyl)propionic acid as a new fluorogenic reagent for amine oxidase assays.

A detailed procedure of a new and extremely sensitive fluorometric assay for amine oxidases is presented. Hydrogen peroxide, produced by the oxidase reaction, reacted with 3-(p-hydroxyphenyl)propionic acid in the presence of peroxidase to yield a fluorescent compound by which enzyme activity could be determined. The enzyme reaction was terminated by NaOH solution, which increased the fluorescence intensity three- to fivefold. The detection limit thus obtained was as little as 0.02 nmol. The alkalinization also contributed to stopping the enzyme reaction and to the clarification of assay mixtures containing turbid enzyme preparations.

Amine Oxidase (Copper-Containing)↗
PubMed1984

Echocardiographic features of bioprosthetic valve endocarditis.

Abnormal echocardiographic findings in seven cases of bioprosthetic valve endocarditis were confirmed in six at operation. The echocardiograms showed three cases with thickening and increased echo intensity (group 1) and four (group 2) in which vegetations were seen initially without either of the two features in group 1. Two patients in group 1 had vegetations, the causative organism being a streptococcus. Staphylococcus epidermidis was the causative organism in three of the four cases in group 2; in two of these rapidly growing vegetations were detected. The large vegetations obstructed the ostium of the bioprosthetic valve. Thus if vegetations are detected in cases in which staphylococci are the causative bacteria surgery should be performed as soon as possible. In patients who develop a fever after bioprosthetic valve replacement and especially in those with evident bacteraemia echocardiography should be repeated frequently so that lesions may be detected early.

Adult↗
PubMed1984

Analysis of blood flow in pulmonary hypertension with the pulsed Doppler flowmeter combined with cross sectional echocardiography.

Blood flow patterns were analysed at nine points in the pulmonary area using the pulsed Doppler technique combined with cross-sectional echocardiography in 53 patients with heart disease and 10 healthy subjects. In subjects with a normal pulmonary artery pressure the blood flow pattern in systole showed a gradual acceleration and deceleration with a rounded summit in mid systole, designated the round type. In patients with pulmonary hypertension it showed a rapid acceleration and early deceleration with a sharp peak in early systole, designated the triangular type. The acceleration time index, defined as the ratio of the time interval from the beginning to the peak of ejection to the ejection time, showed a significant inverse correlation with mean pulmonary artery pressure. In pulmonary hypertension a prominent reverse flow occurred in the right posterior part of the pulmonary trunk during mid-systole and early diastole, indicating the presence of a vortex. Similar flow patterns were also seen in patients with idiopathic pulmonary artery dilatation. The factors responsible for the triangular type were principally the reduced capacitance and increased impedance of the pulmonary vascular tree. Those responsible for the reverse flow were the curved path of the blood flow and dilatation of the pulmonary artery.

Adult↗
PubMed1984

Doppler echocardiographic features of coronary arteriovenous fistula. Complementary roles of cross sectional echocardiography and the Doppler technique.

The Doppler echocardiographic features of coronary arteriovenous fistula were investigated in eight patients with left or right coronary arteriovenous fistulas who had a continuous heart murmur in the upper precordial area and whose diagnoses were confirmed by coronary angiography. In four patients the dilated lumen of the coronary arteriovenous fistula was visualised by cross sectional echocardiography. Of these, three showed abnormal unidirectional continuous flow signals with broad velocity spectra in the fistula. Abnormal, powerful, unidirectional or bidirectional continuous Doppler signals were detected in part of the pulmonary artery in two of the eight patients, in part of the right ventricle in two, and in part of the right atrium in one; these signals were interpreted as indicating shunt flow. Although the opening of the fistula was difficult to visualise by cross sectional echocardiography, the pulsed Doppler technique helped identify the site in patients with dilatation of the coronary artery. In the remaining three patients with a small shunt no abnormal findings were obtained with cross sectional echocardiography or the Doppler technique. The size of the fistula below which no abnormal findings may be obtained by Doppler echocardiography still needs to be determined.

Adult↗
PubMed1984

Mitral valve abnormalities in patients with right ventricular pressure overload. Analysis by real time cross sectional echocardiography.

Abnormalities of the mitral valve in patients with pulmonary stenosis, tetralogy of Fallot, and pulmonary hypertension with right ventricular pressure overload were studied by real time cross sectional echocardiography. Dislocation of the anterior and posterior mitral leaflets at the coaptation zone in systole was present in 16 of 46 cases: nine of 11 (82%) cases of pulmonary hypertension, four of 20 (20%) cases of tetralogy of Fallot, and three of 15 (20%) cases of pulmonary stenosis. The incidence was highest in patients with pulmonary hypertension. In eight of the 16 patients with mitral valve lesions, mitral regurgitation was seen on left ventriculograms or cross sectional Doppler echocardiograms. The dislocation was located near the posteromedial commissure of the anterior mitral leaflet in all cases. These findings are similar to the mitral valve abnormalities seen in patients with secundum atrial septal defect, and therefore may be due to a common cause. No relation could be found between the left ventricular deformity index and the incidence of dislocation of the mitral leaflets. Thus, the reason why this mitral valve abnormality occurs in conditions with right ventricular pressure overload could not be established.

Adolescent↗