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O Kinoshita

Publications and source records attributed to O Kinoshita.

At least 19 recordsLinked to original sources
PubMed1992

Frequency analysis of signal-averaged electrocardiogram in patients with right ventricular tachycardia.

OBJECTIVES: The purpose of this study was to analyze the frequency content of signal-averaged electrocardiograms (ECGs) in patients with idiopathic ventricular tachycardia of right ventricular origin and in patients with arrhythmogenic right ventricular dysplasia. BACKGROUND: The late potentials in the time domains are usually found in patients with arrhythmogenic right ventricular dysplasia. They are not usually found in patients with idiopathic ventricular tachycardia of right ventricular origin. METHODS: Fast Fourier transform analysis of signal-averaged ECGs was performed with the use of a Blackman-Harris window in 43 subjects: 20 normal volunteers (group I), 12 patients with idiopathic ventricular tachycardia of right ventricular origin (group II) and 11 patients with arrhythmogenic right ventricular dysplasia (group III), and the frequency spectrum was displayed in a three-dimensional graph. Area ratio (ratio of the area under the spectral plot from 40 to 120 Hz to the area from 0 to 120 Hz) was calculated in all subjects. RESULTS: Area ratio was significantly higher in group II than in group I (243 +/- 45 vs. 196 +/- 15, p < 0.01) and significantly higher in group III (396 +/- 51) than in group I or II (p < 0.001). The high frequency components in group II were confined within the QRS complex in the three-dimensional graph, whereas those in group III extended outside the QRS complex. CONCLUSIONS: Frequency analysis of the signal-averaged ECG with fast Fourier transform analysis can detect the high frequency components in patients with right ventricular tachycardia, including idiopathic ventricular tachycardia and arrhythmogenic right ventricular dysplasia.

Adult↗
PubMed1992

Spectral analysis of signal-averaged electrocardiograms in patients with idiopathic ventricular tachycardia of left ventricular origin.

BACKGROUND: The signal-averaged ECG has been used to detect late potentials, and it is considered a noninvasive marker for areas of slow conduction requisite for reentrant arrhythmia. Late potentials are not usually found in patients with idiopathic ventricular tachycardia (VT); nevertheless, fragmented electrograms are often recorded in those patients during endocardial mapping. The purpose of this study was to investigate the spectral content of the signal-averaged ECGs with use of fast Fourier transform analysis (FFT) in patients with idiopathic VT of left ventricular origin. METHODS AND RESULTS: Signal-averaged ECGs were recorded in 12 patients with idiopathic VT originating from the left ventricle (group 1) and 25 age-matched normal volunteers (group 2). Frequency analysis with FFT was performed with a Blackman-Harris window in a segment length of 120 msec from 40 msec before the end of the QRS complex, and the frequency spectrum was displayed in a three-dimensional graph. Area ratio 1 (area of 20-50 Hz/area of 10-50 Hz) and area ratio 2 (area of 40-100 Hz/area of 0-40 Hz) were calculated in all subjects. Late potentials defined by the time domain were negative in all subjects. The area ratios of group 1 were significantly higher than those of group 2. High-frequency components in the three-dimensional graph were confined within the QRS complex. CONCLUSIONS: These results suggest that frequency analysis of signal-averaged ECGs with FFT is an available method for detecting the high-frequency component within the QRS complex in some patients with idiopathic VT of left ventricular origin.

Adult↗
PubMed1991

Differential effects of endothelin-1 and big endothelin on canine kidneys.

Renal effects of endothelin-1 (ET-1, human, 1-21) and the equivalent molar concentration of big ET (human, 1-38) and the contributions of prostaglandins and endothelium-derived relaxing factor to these actions were examined. Intrarenal infusion of ET-1, at a dose of 0.4 pmol/kg/min, decreased renal blood flow (RBF), glomerular filtration rate (GFR), and urine output (V) to 62, 70, and 45% of control values, respectively. Additional aspirin-DL-lysine (ASP) treatment (25 mg/kg) caused marked decreases in RBF, GFR, and V to 20, 14, and 9% of control values, respectively. During ET-1 infusion, intrarenal infusion of NG-monomethyl-L-arginine (L-NMMA, 1 mumol/min) caused decreases in RBF, GFR, and V. In another group, intrarenal infusion of big ET at a dose equivalent to that of ET-1 did not significantly affect RBF, GFR, or urine output, which were 95, 107, and 84% of control values, respectively. Additional ASP treatment decreased these values to 78, 69, and 52% of control values, respectively. L-NMMA infusion during big ET infusion showed little effect on renal function. Our study demonstrated that intrarenal infusion of ET-1, at a dose of 0.4 pmol/kg/min, caused significant hemodynamic and functional changes in the canine kidney compared with an equivalent molar concentration of big ET.

Animals↗
PubMed1991

Immunoreactive endothelin-1 contents in brain regions from spontaneously hypertensive rats.

To investigate the possible role of brain endothelin-1 (ET-1) in hypertension of spontaneously hypertensive rats (SHRs), we measured immunoreactive (ir) ET-1 contents in brain regions as well as plasma ir-ET-1 levels in SHRs aged 4-5 and 12-14 weeks and age-matched Wistar-Kyoto rats (WKY) with a radioimmunoassay for ET-1. Systolic blood pressures of SHR aged 4-5 and 12-14 weeks were significantly higher than those of corresponding WKY. Significant amounts of ir-ET-1 were detectable throughout the discrete brain regions analyzed in both strains; higher ir-ET-1 contents in structures such as thalamus, hypothalamus, midbrain, pons, medulla, and cerebellum, with the lowest in cerebral cortex, were observed. A reverse-phase high-performance liquid chromatography of the brain extracts revealed the presence of both a major component identical to the elution position of synthetic ET-1 and a minor component possibly corresponding to its oxidized form. When compared, ir-ET-1 contents in all brain regions analyzed were lower in SHRs than in WKY rats. This strain-related change of ir-ET-1 contents was significant in the medulla at 4-5 weeks of age, and in all brain regions except hypothalamus at 12-14 weeks of age. Plasma ir-ET-1 levels, in contrast, were comparable between SHRs and WKY rats. These results suggest that brain ET-1 may be involved in the development and the maintenance of hypertension in SHRs.

Aging↗
PubMed1991

Acute and chronic effects of anti-endothelin-1 antibody on blood pressure in spontaneously hypertensive rats.

To evaluate the significance of endogenous endothelin (ET) in the maintenance of blood pressure in hypertensive and normotensive conditions, we examined the acute and chronic effects of anti-ET-1 antibody in spontaneously hypertensive rats (SHRs) and Wistar-Kyoto (WKY) rats. Immunoglobulin (Ig) solution purified from anti-ET-1 rabbit serum was injected intravenously in conscious rats aged 12-14 weeks (SHR: n = 7, WKY: n = 7). In the control group (SHR: n = 5, WKY: n = 4), Ig prepared from nonimmune rabbit serum was administered. One week after the first injections of Ig, second intravenous injections were given. After the intravenous injections of ET-1 antibody, there were no significant changes in directly measured blood pressure (BP) for up to 60 min in both strains. On the first, third, and seventh days after the first administration of ET-1 antibody, as well as on the first, third, and seventh days after the second injection, there were no appreciable differences in BP between SHR treated with anti-ET-1 antibody and SHR with control Ig. No significant changes in BP were observed throughout the observation period in WKY groups. Plasma levels of immunoreactive ET-1 were similar in SHR and WKY. This study suggests that circulating ET may not play a significant role in the maintenance of hypertension in SHRs or in the regulation of blood pressure in WKY rats.

Animals↗
PubMed1991

A case of diabetic non-ketotic hyperosmolar coma with an increase with plasma 3-hydroxybutyrate.

We have seen a case of "diabetic non-ketotic hyperosmolar coma" with ketosis. An 84-year-old man was brought into the hospital in a deeply comatous and dehydrated state. The initial blood glucose level was 1252 mg/dl with plasma osmolarity of 435 mOsm/l, but no ketonuria was detected by the nitroprusside method (Ketostix). However, the plasma 3-hydroxybutyrate (3-OHBA) level was 5 mM in a newly developed bedside film test. The serum ketone bodies were later found to be 5.56 and 0.82 mmol/l for 3-OHBA and acetoacetate (AcAc), respectively. A marked increase in glucagon, cortisol and ADH with renal dysfunction (creatinine 5.0 mg/dl) were noted. An abnormal electrocardiogram, occular convergence and chorea like movement disappeared after correction of metabolic disturbances. The moderate level of IRI (14 microU/ml) on admission and a good response to glucagon 2 months after admission also indicate that the present case is a typical hyperosmolar non-ketotic coma. Because of a preferential increase in 3-OHBA, ketonuria seemed to be absent in the regular nitroprusside test. Marked dehydration is thought to cause renal dysfunction, and the increase in ADH may have helped to prevent further aggravation of ketoacidosis. We propose to change the term hyperosmolar non-ketotic coma (HNC) to diabetic hyperosmolar coma (DHC), because sometimes patients with hyperosmolar non-ketotic diabetic coma are ketotic, as seen in the present case. Determination of 3-OHBA or individual ketone bodies in blood is important and essential for the differential diagnosis of diabetic coma. The diagnosis of either ketoacidotic or hyperosmolar coma should be made depending on the major expression of ketoacidosis or hyperglycemic hyperosmolarity.

3-Hydroxybutyric Acid↗
PubMed1991

Doppler echocardiographic assessments of left ventricular diastolic filling in patients with amyloid heart disease.

Twenty-eight patients with amyloid heart disease, 9 with primary and 19 with familial amyloidosis, were examined by Doppler echocardiography to characterize transmitral flow velocity patterns and to assess restrictive ventricular hemodynamics. Six of the 28 patients had restrictive ventricular physiology, and the remaining 22 did not. Patients with a restrictive filling process had marked ventricular wall thickening with depressed fractional shortening. The transmitral flow velocity patterns in patients with restriction were characteristically manifested by the increased peak flow velocity and shortening of rapid diastolic filling, which was associated with a reduced flow velocity in atrial systole. In the 22 patients without restriction, the left ventricular filling patterns were subclassified as 1) filling patterns with the prolonged isovolumic relaxation time and reduced early diastolic filling, as well as enhanced atrial contribution to ventricular filling (16 patients with mild echocardiographic abnormalities), 2) normal filling patterns with normal echocardiograms (4 patients), and 3) normal filling patterns, with moderate ventricular wall thickening (2 patients). These findings suggested that restrictive ventricular hemodynamics can be characterized by the transmitral velocity pattern and that patterns of left ventricular diastolic filling are markedly varied depending on the magnitude of myocardial amyloid deposition in patients with amyloid heart disease.

Adult↗
PubMed1990

Computerized M-mode echocardiographic assessment of left ventricular diastolic function in patients with familial amyloid polyneuropathy.

To determine left ventricular diastolic properties in patients with familial amyloid polyneuropathy, 23 patients were studied by digitized M-mode echocardiography and were compared with 15 age-matched normal subjects. None of the patients had restrictive ventricular physiology and all but two showed normal left ventricular fractional shortening. Both the normalized peak rate of diastolic increase in left ventricular internal dimension and the normalized peak rate of diastolic thinning of posterior wall were significantly lower in patients than in normal subjects (2.0 +/- 0.8 vs 3.0 +/- 0.4 sec-1; p less than 0.001, and 2.5 +/- 1.2 vs 5.8 +/- 1.0 sec-1; p less than 0.001, respectively). The left ventricular isovolumic relaxation time in patients was 91.5 +/- 22.2 msec, compared with 64.0 +/- 2.6 msec in normal subjects (p less than 0.001). Of the 18 patients without clinical evidence of overt heart disease, 12 had normal ventricular wall thickness and normal fractional shortening, but 10 of the 12 exhibited some abnormalities in diastolic properties. In addition, indexes of diastolic function were significantly related to ventricular wall thickness alone. These findings indicate that left ventricular diastolic abnormalities precede the development of clinically overt heart disease, ventricular wall thickening, and systolic dysfunction and may be related to intramyocardial amyloid infiltration with resultant fibrosis in patients with familial amyloid polyneuropathy.

Adult↗
PubMed1990

[Usefulness of combining a immunological fecal occult blood test (latex method) with a chemical test (guaiac method)].

A combination tests, using the latex and guaiac methods, has been carried out in 123 patients with a gastrointestinal disease and in 38 controls. The latex method was positive in 8% of the 38 controls, in 84% of 32 colorectal carcinoma patients, in 42% of 24 colonic polyp patients, in 22% of 9 gastric carcinoma patients, and in 22% of gastric ulcer patients in an active phase of their illness, whereas the guaiac method was positive in 39%, 81%, 58%, 78%, and 89% in the same order, respectively. From the above, a combination of both methods was found useful for the screening of hemorrhage in the gastrointestinal tract.

Colonic Polyps↗
PubMed1989

Radionuclide angiographic assessment of left ventricular diastolic filling in amyloid heart disease: a study of patients with familial amyloid polyneuropathy.

To assess left ventricular diastolic filling in amyloid heart disease, 17 patients with familial amyloid polyneuropathy and 20 normal subjects were examined by radionuclide angiography. None of the patients showed clinical evidence of restrictive cardiomyopathy. All but two patients had normal left ventricular ejection fraction. Peak filling rate was significantly lower and time to peak filling rate was significantly greater in patients than in normal subjects (2.60 +/- 0.52 versus 3.10 +/- 0.44 EDV/s, p less than 0.001, and 215 +/- 53 versus 147 +/- 18 ms, p less than 0.001, respectively). The mean left ventricular filling volume during rapid diastolic filling and atrial systole in patients was 54.5 +/- 19.5% and 44.2 +/- 21.6% of the stroke volume, respectively, compared with 83.8 +/- 6.6% (p less than 0.001) and 20.0 +/- 6.0% (p less than 0.001), respectively, in normal subjects. Although 10 of the 14 patients without clinical evidence of overt heart disease had normal ventricular wall thickness as well as normal ejection fraction, 8 of the 10 showed abnormal diastolic filling. In patients with familial amyloid polyneuropathy, indexes of diastolic filling were significantly related to ventricular wall thickness alone. The incidence and magnitude of abnormalities in time to peak filling rate and contribution of rapid filling as well as atrial systole to ventricular filling increased with age and duration of illness. Thus, abnormal diastolic filling can be seen even in the early stage of familial amyloid polyneuropathy and may be related to myocardial amyloid deposition as well as to fibrosis. Careful consideration should be given to age and duration of illness when diastolic filling is assessed in this disorder.

Adult↗
PubMed1989

Variations in hemodynamic and stress hormonal responses in open heart surgery with buprenorphine/diazepam anesthesia.

The use of buprenorphine-diazepam-N2O (60%)-O2 anesthesia in open heart surgery was investigated. The authors examined the hemodynamic changes produced and the response of stress hormones. Twenty adult patients with atrial septal defects undergoing surgical correction were studied in two groups of 10, receiving either 6 micrograms/kg of buprenorphine (B6) or 12 micrograms/kg of buprenorphine (B12) for the induction of anesthesia. Both groups received a subsequent dose of 6 micrograms/kg of buprenorphine with the commencement of extracorporeal circulation (ECC). With surgery, mean arterial pressure showed a transient increase in both groups and thereafter was stable. Heart rate in the B6 group was increased from the onset of surgery to the day after, while the B12 group showed no significant change. Filling pressures showed no change in either group. Plasma catecholamine concentrations in the B6 group, in contrast to the B12 group, increased significantly from midoperation to after completion of the operation (ECC 10 minutes, B6 group v B12 group: plasma norepinephrine 616 +/- 231 v 195 +/- 38 pg/mL, plasma epinephrine 1385 +/- 392 v 572 +/- 132 pg/mL, P less than 0.05). Plasma ADH levels in both groups rose with the commencement of surgery, reaching a peak at ECC 10 minutes (B6 group 88.1 +/- 8.4 v B12 group 124.4 +/- 27.2 pg/mL). However, in contrast to plasma catecholamines, the antidiuretic hormone (ADH) levels in the B12 group remained higher until the first postoperative day. Therefore, patients who received the larger dose of buprenorphine had better control of hemodynamics and catecholamines, but a greater elevation of plasma ADH levels.

Adult↗
PubMed1989

Impaired left ventricular diastolic filling in patients with familial amyloid polyneuropathy: a pulsed Doppler echocardiographic study.

To assess left ventricular diastolic filling in patients with amyloid heart disease 12 patients with familial amyloid polyneuropathy and 15 normal subjects were studied by pulsed Doppler echocardiography. None of the patients had clinical evidence of overt heart disease or restrictive cardiomyopathy and only two of them showed ventricular wall thickening. The peak flow velocity of rapid diastolic filling and the acceleration rate of early diastolic inflow were significantly lower in patients with familial amyloid polyneuropathy than in controls. The pressure half time was significantly longer in patients than in controls. In addition, the peak flow velocity during atrial contraction and the ratio of atrial peak flow velocity to rapid diastolic peak flow velocity were significantly greater in patients than in controls. Although there were no significant correlations between measurements of diastolic filling and clinical findings in patients with familial amyloid polyneuropathy, the ratio of atrial peak flow velocity to rapid diastolic peak flow velocity was significantly related to left ventricular posterior wall thickness. These findings suggest that in patients with cardiac amyloidosis without restrictive cardiomyopathy, abnormal left ventricular diastolic filling, manifested by a reduction in the rate and volume of rapid diastolic filling with enhanced atrial contraction, can be seen even in the early stage of the disease.

Adult↗
PubMed1989

Left ventricular systolic and diastolic time intervals in familial amyloid polyneuropathy.

To determine left ventricular (LV) systolic and diastolic properties in patients with familial amyloid polyneuropathy (FAP), we analyzed simultaneous recordings of the electrocardiogram, phonocardiogram, carotid arterial pulse, and apex cardiogram in 14 patients and 21 normal subjects. LV systolic and diastolic time intervals were measured. Correlations between the intervals and neurologic disabilities, duration of illness, and age were examined. We found that in patients with FAP, 1) LV relaxation was impaired, especially in early diastole, whereas systolic function was generally preserved, 2) abnormal LV relaxation could be seen before the development of both clinically identifiable heart disease and the abnormalities in systolic function, 3) indexes of LV systolic function and relaxation decreased in parallel with the progress of the disease, duration of illness, and age, and 4) electromechanical delay was markedly increased.

Adult↗
PubMed1989

[Hemodynamic significance of diffuse lung uptake of 201Tl in heart diseases].

Clinical significance of diffuse lung uptake of 201Tl was studied in 244 cases of various heart diseases. The grade of lung uptake of 201Tl was assessed by total lung uptake ratio (L/T), maximal lung uptake ratio (Max/T), lung to myocardium or mediastinum counts ratio (M/H or M/Med) and visual grade. L/T, Max/T, M/H and M/Med were directly correlated with pulmonary arterial pressure (PCW), and inversely correlated with cardiac output (CO) and cardiac index (CI). Among them, L/T was the best index to assess PCW, that was correlated with PCW (r = 0.65), CO (r = -0.53) and CI (r = -0.45). The visual grade of 201Tl lung uptake was correlated with L/T, and the increased lung uptake was associated with a higher PCW and a lower CO as well as a lower CI. Diffuse increased lung uptake of 201Tl was observed in 29 of 41 cases (70.7%) with myocardial infarction, 25 of 29 cases (86.2%) with mitral valvular diseases and 9 of 10 cases (90.0%) with combined valvular diseases, in addition, in most cases with left heart failure and cases of NYHA 3 and 4, but that was not rarely observed in cases of NYHA 2 and without left heart failure. In heart diseases, 201Tl myocardial scintigraphy seems to be valuable for detection of left heart failure including pulmonary congestion and interstitial pulmonary edema. Total lung uptake ratio (L/T) may be useful for estimation of PCW, and the visual grade of 201Tl lung uptake may be applicable as routine index for grading of lung uptake of 201Tl.

Aged↗