Shozo Kanaya

Quantitative correlation between cardiovascular and plasma epinephrine response to mental stress

SummaryTo investigate the quantitative correlations between cardiovascular and endogenous catecholamine response to mental stress, we gave a mental arithmetic test to 20 young healthy men. A direct and non-invasive haemodynamic measurement was performed by serial M-mode echocardiography. Heart rate, blood pressure, cardiac output, stroke volume, ejection fraction, left ventricular end-systolic pressure-volume ratio and plasma epinephrine increased over the baseline period during the test. The peripheral resistance and left ventricular end-systolic volume decreased, whereas left ventricular end-diastolic volume and plasma norepinephrine were unaltered. Furthermore, the degree of change in each haemodynamic parameter showing significant reaction, was well correlated with that of the increase in plasma epinephrine. The data suggest that acute mental stress induces endogenous epinephrine secretion resulting in aβ-adrenergic activated state in the cardiovascular system, namely, positive chronotropism, positive inotropism and vasodilatation.

Frequency of valvular regurgitation by color Doppler echocardiography in systemic lupus erythematosus

Abstract We studied valvular regurgitation in patients with systemic lupus erythematosus (SLE) by color Doppler echocardiography. Because valvular regurgitation occurs frequently in normal subjects, 1,2 we matched the patients by age with a control group. Furthermore, the same person examined both patients and normal subjects using the same Doppler echocardiographic apparatus.

Effects of oral repetitive loading of disopyramide on acute-onset atrial fibrillation with concurrent monitoring of serum drug concentration

We investigated the efficacy and safety of oral repetitive loading of disopyramide, for the termination of acute-onset (i.e., therapy started within 2 days after the onset of palpitations) atrial fibrillation (AF) in 96 consecutive patients, with concurrent monitoring of the serum concentration of this agent in fifteen of the patients. Outpatients with AF verified by standard electrocardiogram (ECG) were hospitalized and received disopyramide (200 mg) every 4-6 h, with a maximal dose of 800 mg daily, until the termination of AF under ECG monitoring was obtained. Conversion to sinus rhythm occurred within the first day of treatment in 88 patients (92%), on the second day of treatment in six patients (6%), and on the third and fifth days of treatment in the remaining two patients. No major adverse effects, such as hypotension, congestive heart failure, proarrythmic events or systemic embolism were noted. The serum levels of disopyramide evaluated in fifteen of the enrolled patients were found to be maintained within the therapeutic range throughout the treatment period. In spite of the absence of any placebo-controlled group in this study, these findings suggest that repetitive oral loading of disopyramide (200 mg) with an interval of 4-6 h is effective and safe for the termination of acute-onset AF under a stable therapeutic serum drug concentration, hence offering the possibility of self-medication for patients with episodic AF.

Plasma sulpho-conjugated catecholamine dynamics up to 8 h after 60-min exercise at 50% and 70% maximal oxygen uptakes

AbstractThe prolonged effects of steady-state exercise and meals on plasma sulpho-conjugated catecholamines (CA) after exercise were examined. Seven male subjects exercised on 2 separate days for 60 min at 50% and 70% of maximal oxygen uptake (

Cardiovascular Manifestations in Systemic Lupus Erythematosus : SYMPOSIUM ON SECONDARY MYOCARDIAL DISEASE : 44th Scientific Session of the Japanise Circulation Society

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A 17-year follow-up study of hypertensive and normotensive male university students in Japan

) on a cycle ergometer and then rested, for 8 h sitting in an armchair. A control trial without any exercise was also performed. At 2 h after the end of exercise the subjects were given a meal. The plasma free and sulphated CA, oxygen uptake (

Possible evidence for transmembrane K(+)-H+ exchange system in guinea pig myocardium.

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