Biomedical subjects

K Tobise

Publications and source records attributed to K Tobise.

At least 55 records · Page 3Linked to original sources

PubMed1991

[A case of sleep apnea syndrome with variant angina].

A 56-year-old male was admitted because of respiration arrest during sleep, and precordial crushing sensation which repeatedly occurred early in the morning. He had been hypertensive and aware of daytime sleepiness for ten years. After admission, all night polysomnography was recorded a total of four times. Apnea index was 37.5 times/hour, and central type apnea was predominant. The diagnosis of sleep apnea syndrome was made. In the early morning of the fourteenth day after admission, the patient developed anterior chest pain associated with ST elevation in leads II, III, and aVF of the electrocardiogram. Thus, the case was thought to be complicated by variant angina. There were no anginal attacks during the all night polysomnography recordings. However, a causal relationship between the sleep apnea and variant anginal attacks was suspected. Since both the sleep apnea and the variant anginal attacks tended to occur during the stages of REM sleep, and they are both related to changes in activity of the autonomic nervous system. It was considered that hypoxemia following sleep apnea and/or the hyperventilation after the apneic episodes might be the cause of the variant anginal attacks.

Angina Pectoris, Variant↗

PubMed1991

[Technetium-99m-pyrophosphate myocardial scintigraphy in polymyositis--a case report].

A patient with polymyositis who had cardiac involvement underwent myocardial scan with technetium-99m-pyrophosphate. We used Activity Index for evaluating myocardial uptake of technetium-99m-pyrophosphate, which correlated with the degree of serum creatine phosphokinase elevation. Our findings indicate that these examinations may be helpful for identifying patients who have cardiac involvement and evaluating their response to the treatment with corticosteroids or immunosuppressants.

Cardiomyopathies↗

PubMed1991

[A case of right atrial myxoma--the availability of transesophageal echocardiography in the detection of right atrial myxoma].

A 72-year-old woman had experienced palpitation and fatigue during exertion for two months and was referred to our hospital from her nearby hospital. On physical examination, a systolic murmur was heard in the left fourth intercostal space. A chest X-ray film showed cardiac enlargement (CTR 64%). An ECG showed elevated P waves in leads II, III. Transthoracic echocardiography revealed a large oval heterogeneous mass in the right atrium. Transesophageal echocardiography (TEE) revealed the right atrial mass clearly, which was attached to the atrial septum with a short wide stalk. This mass prolapsed from the right atrium into the right ventricle in diastole. And there were some cysts in the homogeneous high-echoic lesion. The chest CT and MRI also showed the mass in the right atrium. However, these images were not clear. Surgical excision of the mass was undertaken. A solid mass measuring 75 x 50 x 45 mm was attached to the fossa ovalis with a wide short stalk. There were several cysts in the mass. Pathological examination showed myxomatous tissue. In this case, TEE was the most valuable means for evaluation of the right atrial mass.

Aged↗

PubMed1990

Changes in the pulmonary vascular input impedance in patients with atrial septal defect after surgical correction.

In order to evaluate whether there is pulmonary vascular disease in patients with atrial septal defect (ASD), we used the pulmonary vascular input impedance to estimate the stiffness of the pulmonary vessels with before and after surgical intervention. Ten control subjects and 11 patients with ASD (9 operable and 2 inoperable) were examined. In preoperative patients the decreased total pulmonary resistance (Rin) and pulmonary vascular resistance appeared to open new parallel vascular channels with increased blood flow. Further, there were no significant differences in the pulmonary vascular input impedance spectrum and phase, and characteristic impedance among control subjects, preoperative and postoperative patients. Although distensibility of the pulmonary vascular wall in operable patients was similar to that in control subjects, an excessive elevation in Rin and input impedance modulus was observed in inoperable patients. The results demonstrate that the normal input impedance spectrum and phase in patients with ASD is predictive of a good prognosis after successful surgical correction.

Adolescent↗

PubMed1990

Ca2(+)-induced contraction and hyperreactivity of pulmonary arterial smooth muscle in monocrotaline-treated rats.

The mechanism of progressive pulmonary hypertension induced by monocrotaline (MCT) remains controversial. To determine whether or not functional changes in pulmonary arterial smooth muscle contribute to the development of pulmonary hypertension, we examined the reactivity of isolated pulmonary artery segments 7, 14 and 21 days after a single subcutaneous injection of MCT. In Ca2(+)-free buffer, pulmonary arteries from MCT-treated rats contracted when CaCl2 was added without any other stimulation. The pulmonary artery exposed to MCT also exhibited hyperreactivity to KCl and 5-hydroxytryptamine. These functional changes in the pulmonary artery preceded the elevation of right ventricular systolic pressure and right ventricular hypertrophy. The contraction in response to Ca2+ suggests that the pulmonary artery of rats given MCT may be contracted in situ. Vasoconstriction due to these alterations may play an important role in the development of pulmonary hypertension according to this model.

Animals↗

PubMed1990

[Respiratory pathophysiology during sleep in patients with myotonic dystrophy].

Myotonic dystrophy is a genetic disorder inherited as an autosomal dominant trait. It is known to be associated with endocrine dysfunction, polar cataracts, cardiac abnormalities and other conditions. Respiratory distress constituents the principal problem in myotonic dystrophy. The author investigated postural change of respiratory function in 12 patients with myotonic dystrophy (MYD), and 7 patients with limb-girdle dystrophy (LG) and overnight polysomnography was performed on 10 patients with MYD and 5 patients with LG. The respiratory function in seated posture showed no significant difference between LG and MYD, but in patients with MYD, the vital capacity and the expiratory reserve volume in a supine posture was reduced in comparison to that during seated posture. However, the respiratory function in patients with LG was not significantly different in seated and supine postures. Also, in patients with MYD, there was a significant decrease in arterial PO2 from the seated posture to the supine posture, without a significant change in the arterial PCO2. However, in patients with LG, there was no significant change in arterial blood gas analysis parameters. It was speculated that these findings concerning respiratory function and blood gas analysis in patients with MYD were caused by the involvement of the diaphragm. In the supine posture, the diaphragm shifted to the cranial position because of the abdominal contents rising into thorax, therefore the lung volume was reduced and the ventilation-perfusion ratio deteriorated. The changes of respiratory function parameters and PaO2 were partly responsible for the hypoxemia observed during sleep in patients with MYD. Overnight polysomnography showed that 9 of the 10 patients with MYD and 1 of the 5 patients with LG presented apneas during sleep, particularly during REM, stage 1 and stage 2. Almost all apneas were central type, with a low percentage of obstructive apneas and the apnea index was 19.0/h (mean) in MYD, 6.5/h in one case of LG. These result strongly suggest that sleep apnea is of central origin, but the distinction between a central and an obstructive etiology is difficult in neuromuscular disease and particularly when a disorder of central ventilatory responsiveness is suspected. The respiratory function of MYD and LG in seated and supine postures was studied and overnight polysomnography performed. It was emphasized that it was important for the respiratory care of neuromuscular disease to consider the influence of postural changes in the respiratory function. The present series of studies revealed central sleep apnea in the patients with myotonic dystrophy.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

PubMed1988

[Obstructive sleep apnea syndrome with reversible interventricular septal displacement during sleep: a case report].

A case of the obstructive sleep apnea syndrome revealed reversible leftward displacement of the interventricular septum by echocardiography during sleep. A 46-year-old housewife with congenital micrognathia was admitted to our hospital complaining of severe dyspnea and general edema. On admission, she had severe hypoxemia (PaO2 = 35.2 mmHg), pulmonary hypertension (mean pulmonary artery pressure = 70 mmHg) and right heart failure. Her echocardiograms revealed enlargement of the right ventricle with a flattened left ventricle. A sleep study performed after partial resolution of her right heart failure disclosed that severe hypoxemia and pulmonary hypertension (mean pulmonary artery pressure = 70 mmHg) occurred after relatively long periods of apnea. With vigorous inspiratory efforts during sleep apnea, transient enlargement of the right ventricle and leftward displacement of the septum causing the flattened left ventricle were observed echocardiographically. A concomitant decrease in left ventricular inflow velocities was also observed by the pulsed Doppler method. However, these findings immediately returned to normal with the resumption of ventilation. We concluded that these repetitive apneic events due to obstruction of the airway during sleep might accelerate complete eventual pulmonary hypertension and right heart failure.

Echocardiography↗

PubMed1988