Search PubMed⌕ Search

Biomedical subjects

S Okubo

Publications and source records attributed to S Okubo.

At least 181 records · Page 10Linked to original sources
PubMed1986

An infiltrative right ventricular myxoma.

Computed tomographic findings in a 71-year-old patient with an infiltrative right ventricular myxoma are described. The findings included multiple lesions in the right ventricle and stenosis of the trunk of the pulmonary artery.

Aged↗
PubMed1986

Relevance of location of defect and pulmonary vascular resistance to the intracardiac pattern of left-to-right shunt flow in dogs with experimental ventricular septal defect.

Left-to-right (L-R) shunting across a ventricular septal defect (VSD) often involves a direct VSD-pulmonary arterial component (jet) that surges from the VSD immediately into the pulmonary artery. We used the thermodilution technique in dogs with acute experimental VSD to quantify this component. In dogs with supracristal VSD (n = 7), the direct component represented 76 +/- 4% (mean +/- SE) of the total L-R shunt on average, vs 39 +/- 7% (p less than .001) of the total in dogs with infracristal VSD and the same level of L-R shunting (n = 6). The direct component can be expected to impose additional hyperkinetic forces on the pulmonary artery since it is driven by the left ventricular pressure. Although not yet clinically proven, we speculate therefore that patients with supracristal VSD may be at greater risk of becoming jeopardized by late-onset pulmonary vascular obstructive disease. Since a part of the total shunt other than the direct component dropped into the right ventricle, the right ventricle bore only 24% of the total shunt in supracristal VSD, but 61% in infracristal VSD. We also found that the amount of direct component was decreased, and therefore another part must have increased, as the pulmonary vascular resistance was artificially raised. As a second speculation, therefore, we suggest that patients with supracristal VSD may have less enlargement of the right ventricle than those with infracristal VSD before pulmonary hypertension develops.

Animals↗
PubMed1986

Respiratory dysfunction following acute and chronic pump failure of the heart.

In order to explore pulmonary dysfunction originating in cardiac decompensation, acquired heart diseases were classified into three selected categories; chronic compensated heart, chronic decompensated heart and acute decompensated heart with severe alveolar edema. Pathophysiology in each category was investigated. Hemodynamic variables were measured by cardiac catheterizations and a variety of pulmonary functions based on respiratory physiology were studied. Severe alveolar edema due to acute pump failure of the heart revealed a significant inverse correlation between PaO2 and PaCO2 indicating the appearance of decreased effective alveolar ventilation with markedly decreased PaO2. A-aDO2 remained still high despite a complete resolution of alveolar edema. There are some possibilities that pulmonary dysfunction might be accelerated by repetition of acute cardiac decompensation in chronic heart diseases. Chronic pulmonary involvements caused by chronically decompensated heart must be stressed most important for comprehensive treatments of cardiac pump failure. Lung volumes considerably decreased but ordinarily there was no obvious airflow obstruction in the large central airways. Chronic compromised lung with giant left atrium, however, showed appreciable decrease in FEV1% (FEV1/FVC), MMF, V50 and V25, indicating an apparent evidence of both central and peripheral airway obstructions. Patients with CTR over 70% were more seriously involved with a significant reduction in lung volumes in addition to total airway obstructions. Under these situations an inverse correlation between PaO2 and PaCO2 in chronic decompensated heart was observed showing a contrast difference in chronic compensated heart.

Adult↗
PubMed1985

Clinical spectrum and endomyocardial biopsy findings in eosinophilic heart disease.

Fourteen cases of heart disease with hypereosinophilia were analyzed employing conventional cardiologic methods, including echocardiography, cardiac catheterization, and endomyocardial biopsy. The cases were divided into four types: Acute carditic (endocarditis, myocarditis, pericarditis; five cases); ventricular dilation (three cases); restrictive (three cases); electric disturbance (three cases). Biopsy revealed significant changes in all cases. In one case of the ventricular dilation type, endomyocardial fibrosis with myocardial degeneration was seen, and in another case mural thrombus formation was shown to be present. In three cases of the restrictive type, endomyocardial fibrosis (EMF) was observed. In two cases of the electric disturbance type, minor right ventricular myocardial degeneration was observed. In two of the three cases of the carditic type and in three of eight cases in other categories, postmyocarditic changes were observed. The course of the disease compared with the type of disorder revealed a short course in the carditic type and a longer course, ranging from 2 to 24 years, with one exception, in the other types. It is also confirmed that the various histopathologic changes can be related to particular clinical presentations. We have shown that the basic changes in eosinophilic heart disease are not restricted to the endomyocardium and that they occur in various parts of the heart causing more widespread manifestations. The more comprehensive term "eosinophilic heart disease" is a preferable description.

Adolescent↗
PubMed1985

Effects of pulmonary hemodynamics on lung function in adult patients with atrial septal defect.

To clarify the relationship of pulmonary function with differing severity of atrial septal defect (ASD) and to assess the effects of pulmonary hemodynamics on these functions, we classified 101 patients with adult ASD by their pulmonary arterial mean pressure (PAm) and pulmonary blood flow (Qp), and compared details of pulmonary functions between pairs of groups. Classification was by drawing lines at the PAm of 20 mmHg and the Qp of 10 L/min. Group I was the low pressure-low flow group, Group II the low pressure-high flow group, Group III the high pressure-low flow group, and Group IV the high pressure-high flow group. Vital capacity as the percentage of predicted (%VC) was low in Groups III and IV. There were no significant differences in the ratio of forced expiratory volume in one second to forced vital capacity (FEV1%), flow at 25% forced vital capacity and closing volume as the percentage of predicted (%V25, %CV/VC) between each group. Both maximum midexpiratory flow rate and flow rate at 50% forced vital capacity as the percentage of predicted (%MMEF, %V50) in Group III with the most severe ASD, were significantly low. Pulmonary diffusing capacities for carbon monoxide as the percentage of predicted (%DLco) exceeded 100% in all groups, and tended to decrease with increases of PAm without relation to Qp. Pulmonary dysfunctions in adult ASD were mainly due to restrictive changes accompanied by obstructive change in proportion to the decrease of VC. Peripheral airway obstructions are mild in ASD and these might be caused by lower pressure of left atrium and no existence of pulmonary venous congestion in ASD, even in the most severe group.

Adolescent↗
PubMed1985

Multiinstitutional evaluation of local injection of absolute ethanol as the new hemostatic method for upper G-I tract bleeding.

Local injection of absolute ethanol was proven effective for hemostasis of gastrointestinal bleeding in our fundamental (Asaki et al. 1983a) and clinical (Asaki et al. 1983b) studies. The purpose of the present paper is to report the results obtained in 258 hemorrhagic foci in 152 unselected cases treated with this method at 6 major hospitals in the Tohoku area in Japan. Sixty (39%) of these 152 cases had shock symptoms due to hemorrhage. Gastric and duodenal ulcers were responsible for the hemorrhage in about 90% of the cases in which our method was applied to hemostasis. Eighty-nine (59%) of the 152 cases had some form of complications such as malignant tumors or liver cirrhosis. Hemorrhage due to postoperative stress ulcer after major surgeries including renal implantation or laryngectomy for resection of cancer was seen in 20 cases (13%). The condition of hemorrhage immediately before the treatment with our technique was classified as spouting hemorrhage for 8 foci (3%), pulsating hemorrhage for 22 foci (9%), adhesion of clot for 179 foci (69%), and hemorrhage from veins and capillaries for 49 foci (19%). In all of these cases temporary hemostasis was obtained. Rebleeding occurred in 17 cases (7%) including 5 cases in which hemostasis was successfully obtained by the repeated use of our method. In 4 of the 17 cases, in which repeated endoscopy was infeasible, emergency surgery was performed. In the remaining 8 lesions in 8 cases, new bleeding or rebleeding occurred more than 1 week after the initial hemostasis had been obtained. Six of these 8 cases died from rebleeding due to DIC syndrome. With our method complete hemostasis was obtained in 144 of 152 cases (95%) including 11 cases (7%) which underwent elective surgical operation.

Adolescent↗