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Biomedical subjects

H Fukuzaki

Publications and source records attributed to H Fukuzaki.

At least 253 records · Page 14Linked to original sources
PubMed1983

A long-term follow-up study of acute viral and idiopathic myocarditis.

In order to clarify the prognosis of myocarditis and the relationship between myocarditis and idiopathic cardiomyopathy, 20 patients with myocarditis (one with Coxsackie B; one with rubella and 18 with idiopathic myocarditis) were followed up for a long period using echocardiography and Holter electrocardiographic monitoring. The follow-up period was 49.1 +/- 39.3 months (mean +/- SD). Subjects were classified into the following 4 groups according to their prognoses, left ventricular end-diastolic dimensions (LVDd) and the presence of absence of life-threatening ventricular arrhythmias: Group I with a fatal prognosis, Group II with LVDd greater than or equal to 55 mm, Group III with LVDd less than 55 mm but associated with life-threatening ventricular arrhythmias, and Group IV with LVDd less than 55 mm and with no life-threatening ventricular arrhythmias. Patients of Group I (2 cases) had a marked left ventricular dilatation and a poor left ventricular function just before death. Patients of Group II (5 cases) had left ventricular and left atrial dilatation, and 2 of them had serious ventricular arrhythmias. All 3 patients of Group III had ventricular arrhythmia (ventricular tachycardias, coupled premature ventricular contractions and multifocal premature ventricular contractions, respectively), and 2 of them had asymmetric septal hypertrophy. All 10 patients of Group IV had no residual cardiac abnormalities. In conclusion, 50% of 20 myocarditis patients had residual cardiac abnormalities; 6 patients (2 of Group I and 4 of Group II) were complicated by left ventricular dilatation, simulating dilated cardiomyopathy, and 3 (one of Group II and 2 of Group III) showed asymmetric septal hypertrophy, simulating hypertrophic cardiomyopathy.

Acute Disease↗
PubMed1983

Changes of serum total cholesterol and triglyceride levels in normal subjects in Japan in the past twenty years. Research committee on familial hyperlipidemia in Japan.

Serum lipid levels of 10,977 normal Japanese subjects in 1980 were determined by a joint study of 14 institutions, specializing in lipid research, located in 9 districts of Japan. The data obtained were compared with those in 1960 and 1970. Total cholesterol (TC) levels in 1980 increased with age except for the 1st decade and reached maximum (205 mg/dl) at the 7th decade. The mean value in any age was higher than that of 20 years ago by 10-15 mg/dl. Triglyceride (TG) levels also increased with age and reached maximum (130 mg/dl) at the 7th decade. The mean values of subjects over the 5th decade were higher than those of 10 years ago by 10-20 mg/dl. In contrast with TC and TG, HDL-cholesterol levels were highest at the 1st decade and declined gradually with age. TC and TG levels of younger age (1st to 3rd decade) were equal to or even higher than those of Americans in 1972-76. It was concluded that serum lipid levels of Japanese have increased in the past 20 years and approached to the levels of Europeans and Americans.

Adolescent↗
PubMed1983

Assessment of left ventricular dysfunction by thallium-201 lung uptake during exercise in coronary artery disease.

To determine the clinical significance of an increased thallium-201 (Tl-201) activity in the lung and of its clearance from the lung after exercise, computer-quantitated Tl-201 lung activity was measured and compared with hemodynamic parameters at rest and during exercise in 35 patients with coronary artery disease (CAD). All patients underwent a supine bicycle ergometer exercise test and mean pulmonary artery wedge pressure (PAWP) was measured by a Swan-Ganz catheter. Coronary angiography was also performed. On computer-generated initial and 2 and a half hours delayed anterior images, regions of interest were selected over the myocardium (M) and lung (L), and the initial L/M ratio and the (initial L)/(delayed L) ratio were calculated as indices of an increased Tl-201 lung uptake and lung clearance, respectively. The initial L/M ratio and the (initial L)/(delayed L) ratio had no significant correlation with mean PAWP at rest and had a weak negative correlation with the resting ejection fraction (r = -0.57 and r = -0.58, respectively). However, both ratios showed good correlations with mean PAWP during peak exercise (r = 0.85 and r = 0.80, respectively), suggesting that they provide useful indices for assessing the severity of exercise-induced left ventricular dysfunction.

Adult↗
PubMed1983

Beneficial effects of the coronary collateral circulation on tachycardia-induced myocardial ischemia during experimental coronary stenosis.

This study was designed to determine whether coronary collaterals have preventive effects on tachycardia-induced myocardial ischemia under partial restriction of proximal coronary artery inflow. Studies were carried out in dogs with developed coronary collaterals and control dogs. ST-elevation in epicardial and intramyocardial electrograms was used for assessing the degree of regional myocardial ischemia. In control dogs with coronary constriction (80% reduction of i.d.) pacing-induced tachycardia produced significant ST-elevation, 1.48 +/- 0.17 mV in the inner layer and 0.79 +/- 0.29 mV in the middle layer at a cardiac rate of 150/min, 3.58 +/- 0.38 mV in the inner layer, 2.73 +/- 0.38 mV in the middle layer, and 1.93 +/- 0.36 mV in the outer layer at a rate of 180/min. In dogs with moderate collaterals ST-segment elevation was only 1.41 +/- 0.18 mV in the inner layer and 0.96 +/- 0.24 mV in the middle layer at a rate of 180/min. In dogs with abundant collaterals there was no significant ST-elevation during tachycardia. These findings indicate that blood supply to the affected myocardium via developed collaterals is sufficient to meet graded increases in metabolic requirements under the condition of limited coronary flow reserve in an experimental model simulating angina pectoris.

Animals↗
PubMed1983

Effects of ergonovine-induced vasoconstriction on the genesis of myocardial ischemia during coronary stenosis in dogs.

We developed a canine model with coronary stenosis produced by intraluminal obstruction with a micro-balloon occluder to assess the role of vasomotor tone of a large coronary artery with a preexisting fixed stenosis in the genesis of myocardial ischemia. Hemodynamic and electrocardiographic responses to ergonovine, an agent capable of provoking coronary spasm, were evaluated. In the absence of coronary stenosis, intracoronary infusion of 4 micrograms/min ergonovine had no systemic and coronary hemodynamic effects. Similarly, with various degrees of external obstruction created by a screw-type metal constrictor, ergonovine had little hemodynamic effects. By contrast, with a stenosis greater than 28.4 +/- 5.0 mmHg in pressure gradient, created by intraluminal obstruction which preserved active arterial vasomotion, ergonovine-induced vasoconstriction produced a marked decrease in coronary blood flow and distal coronary pressure, followed by ST-elevation. These deleterious effects of ergonovine on coronary hemodynamics were reversed completely by intracoronary infusion of nitroglycerin. Our results indicate that the effects of normal coronary arterial vasomotor activity on a stenosed vessel can cause myocardial ischemia.

Animals↗
PubMed1983

Two cases of myocardial infarction with coronary arteriovenous fistula.

Myocardial infarction in the presence of coronary arteriovenous fistula (CAVF) has rarely been reported. Two young male patients with dual abnormalities, an organic stenosis and a CAVF in the left anterior descending artery, were reported. Each fistula originated closely proximal to the stenotic lesion and drained into the main pulmonary artery. It was thought that the coronary steal phenomenon through the fistula further reduced the coronary blood flow distal to the stenosis. Thus, both the stenotic lesion and the fistula possibly contributed to the occurrence of the myocardial infarction. Since angiographic details of myocardial infarction with CAVF have rarely been reported these findings may be important in clarifying the mechanism of myocardial infarction with CAVF.

Adult↗
PubMed1983

[Hypertrophic cardiomyopathy with dilatation of the left ventricle and congestive heart failure: comparison with postmyocarditis cardiomegaly and hypertensive heart failure].

In a total of 114 cases of hypertrophic cardiomyopathy (HCM), four cases were regarded to have dilated left ventricle and congestive heart failure. History of myocardial infarction was not present, and significant narrowing of coronary arteries was not detected in each case. The clinical manifestations were analyzed in the light of the differentiation from postmyocarditis cardiomyopathy (PMC: three cases) and hypertensive heart disease ( HHD : five cases). Representative case was a 47-year-old man with HCM, who showed congestive heart failure developed gradually over the last 20 years. The cardiothoracic ratio increased from 57% to 64% and high voltage of the precordial leads noted initially decreased gradually with normalization of ST-T changes. Meanwhile, a new abnormal Q wave appeared in aVL. The echocardiographic findings at the age of 47 were asymmetric septal hypertrophy and left ventricular enlargement. Myocardial biopsy of the right ventricle done at the same period revealed the marked progression of interstitial fibrosis as compared with that of 15 years ago. Clinical pictures demonstrated that PMC patients were younger than HCM or HHD patients. Abnormal Q waves were observed in three cases of HCM. In the remaining one, the Q wave was not discernible due to superimposed complete left bundle branch block. No abnormal Q waves were observed in cases of PMC and HHD . A high voltage of the left precordial leads with marked ST-T changes suggesting left ventricular hypertrophy was not seen in HCM with dilated left ventricle and HHD . Echocardiographically, the systolic anterior motion was absent in all cases. The left ventricular posterior wall in PMC and HHD was equally hypertrophied both at the apex and base, whereas in three of four cases of HCM, the apical region of the posterior wall was disproportionately hypertrophied. All cases of HCM and PMC showed asymmetric septal hypertrophy, while all the HHD cases except one showed concentric hypertrophy. In HCM, left ventricular end-diastolic dimension and left atrial dimension were increased to 60.0 +/- 6.1 mm and 45.3 +/- 9.4 mm, respectively, which were not different from those of PMC and HHD . Isometric relaxation time was prolonged to 100 msec or more in all cases of HCM, while in only one case of PMC it was prolonged and no prolongation was observed in HHD . Left ventricular wall motion revealed asynergy mainly at the hypertrophic apical area in HCM and PMC, whereas asynergy was found at the hypertrophic area, which was mostly apical, and also in the area without hypertrophy in HHD .(ABSTRACT TRUNCATED AT 400 WORDS)

Aged↗
PubMed1983

[Intracardiac flow pattern in dilated cardiomyopathy studied with pulsed Doppler echocardiography].

Left ventricular (LV) flow dynamics were analyzed by pulsed Doppler echocardiography in patients (pts) with dilated cardiomyopathy (DCM). Subjects consisted of five normal controls, 27 pts with DCM, five with myocardial infarction and five with valvular heart disease. The equipment used was a two-dimensional echocardiograph ( Toshiba SSH- 11A ) coupled with a pulsed Doppler flowmeter ( Toshiba SDS-10A). The long-axis plane through the left ventricle was obtained from an apical transducer position and Doppler flow signals were recorded at the apex (point A), the middle portion (point B), the inflow portion (point C), the portion near the mid-IVS (point D) and the outflow portion (point E) of the left ventricle, respectively. Left ventriculography was performed in all subjects, and ejection fraction (EF), the ratio of the short-axis to long-axis distance in end-diastole, percent shortening of the long axis and percent shortening of the short axis of the left ventricle were measured. Doppler signals of an ejection flow were recorded at points A, B, D and E in the normal controls, while in 27 pts with DCM Doppler signals of an ejection flow were detected only in two pts (7%) at the point A, in three pts (11%) at the point B, 16 pts (59%) at the point D and 27 pts (100%) at the point E. Twelve pts (44%) had abnormal Doppler signals with wide-band spectral pattern at the point C in systole. Toward flow signals in early diastole were recorded at the points A, B, C and D in the normal controls, while in pts with DCM the signals were visualized in only three pts (11%) at the point A, in 27 pts (100%) at the points B and C, and 10 pts (37%) at the point D. EF in pts with DCM was lower than that of the normal controls (36 +/- 11 vs 65 +/- 5%, p less than 0.005). The ratio of the short-axis to long-axis distance of the left ventricle was higher in pts with DCM compared with that of the normal controls (0.82 +/- 0.09 vs 0.60 +/- 0.02, p less than 0.005). Percent shortening of the long axis and the short axis was depressed in pts with DCM compared with the normal controls (11 +/- 5 vs 21 +/- 4%, p less than 0.02 and 15 +/- 6 vs 34 +/- 3%, p less than 0.001, respectively).(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1983

[Two-dimensional echocardiographic findings in a case of arrhythmogenic right ventricular dysplasia].

Two-dimensional echocardiographic findings in a patient with arrhythmogenic right ventricular dysplasia ( ARVD ) were described. A 38-year-old male was admitted to our hospital on January 1982 because of palpitation and dyspnea caused by ventricular tachycardia. A cardiothoracic ratio was 45% and electrocardiogram revealed right axis deviation and T wave inversion in right precordial leads. A QRS configuration during ventricular tachycardia showed left bundle branch block pattern. The right ventriculogram showed dilatation and diffuse hypokinesis of the right ventricle, although the left ventriculogram and the coronary angiogram were normal. Histological findings of both right and left ventricular tissues obtained by endomyocardial biopsy revealed myocytolysis, scarcity of myofibrils and proliferation of collagen fibers, and the final diagnosis of ARVD was established. Echocardiographic examination disclosed right ventricular and right atrial dilatations, hypokinesis of the right ventricular anterior wall and abnormal motion of the interventricular septum. These seemed to be diagnostic of this condition, if right ventricular volume overload including atrial septal defect, endocardial cushion defect, Ebstein's anomaly, tricuspid regurgitation and pulmonary regurgitation was clinically excluded.

Adult↗
PubMed1982

The significance of stenotic lesion in an unoccluded coronary artery. A manifestation of myocardial "ischemia at a distance" during acute coronary occlusion.

This study was undertaken to investigate the significance of stenotic lesion of an unoccluded vessel in a manifestation of myocardial "ischemia at a distance" during acute coronary occlusion. The left anterior descending artery (LAD) was ligated in dogs in which constriction of the circumflex artery (LCx) of different degrees was carried out beforehand. Ischemic changes were detected by epicardial and intramyocardial electrocardiograms. Systemic and coronary hemodynamics were monitored. In dogs without LCx constriction (Group-I) and those with LCx constriction of such a degree as to reduce the percent repayment of the blood flow debt to 150% (Group-II), the LAD-ligation produced no ischemic changes in the LCx area. In dogs with severe constriction of LCx such as eliminating reactive hyperemia (Group-III), an expansion of ischemic damage to the LCx area was observed. Ventricular fibrillation was observed more frequently in Group-III as compared to Group-I and Group-II. After LAD-ligation LCx blood flow was increased in Group-I and Group-II, but remained unchanged in Group-III. After LAD ligation, distal coronary perfusion pressure (DCPP) of LCx remained unchanged in Group-I, while further decrease of DCPP was observed in both Group-II and Group-III. Some dogs in Group-III showed a sudden reduction of the flow associated with a decrease of DCPP after the ligation. These results show that hemodynamic changes, especially a sudden decrease in coronary perfusion pressure after LAD-ligation, play a significant role in inducing ischemic changes in the area perfused by the unoccluded coronary artery with severe stenosis (LCx).

Animals↗
PubMed1982

Clinical evaluation of stress myocardial scintigraphy with thallium-201 in patients with ischemic heart disease. Semiquantitative analysis of single dose myocardial imaging.

In order to evaluate the usefulness of a stress T1-201 myocardial scintigraphy in semiquantifying the myocardial perfusion, 10 normal subjects and 71 patients with coronary artery diseases were studied with sequential imaging over 3 hours. Myocardial to background ration (M/B) in the exercise phase was significantly higher in the normal subject group than in the coronary artery disease groups. Three hours after exercise (redistribution phase), M/B decreased significantly in the normal subject group but remained unchanged in the coronary artery disease groups. Percent change of M/B with exercise was lower in the effort angina pectoris group (97 +/- 11.2%), and the old myocardial infarction group (101 +/- 14.5%) than in the normal subject group (127 +/- 12%). Sensitivity and specificity of this method were 93% and 47%, respectively. Out of 11 patients with variant angina pectoris, 9 patients showed positive scintigram. Of the 9, however, 6 cases were without organic coronary stenosis in the coronary angiography. There was a significant correlation between M/B on redistribution images (RD.M/B) and ejection fraction determined by left ventriculograms (r = 0.61, p less than 0.001), indicating a close relation between the amount of the residual viable myocardium and the left ventricular function. M/B and its percent change with stress T1-201 myocardial scintigraphy reflect the myocardial perfusion and myocardial perfusion reserve and their semiquantitative analysis provides a useful means for detection of ischemic heart disease.

Adult↗
PubMed1982

Adverse response to nifedipine in unstable angina pectoris.

A patient had accelerated attacks of chest pain associated with transient ST elevation or depression in the anterior leads. Coronary angiogram revealed severe multi-vessel disease. Anginal attacks with conspicuous ST depression were induced repeatedly by both oral and sublingual administration of nifedipine. Among various vasodilator drugs tested on this patient, dipyridamole and hydralazine induced anginal attacks. These observations suggest that anginal attacks induced by administration of nifedipine may be related to the augmentation of myocardial oxygen consumption due to increases in cardiac output and heart rate, the coronary steal phenomenon, or an increase in venous return accompanied by the subendocardial underperfusion.

Administration, Oral↗
PubMed1982

Deleterious effects of vasodilating agents. Induction of subendocardial ischemia in dogs with proximal stenosis of coronary artery.

This study was designed to determine how distal vasodilatory stimuli can alter coronary hemodynamics and the appearance of myocardial ischemia in the presence of severe coronary stenosis. In anesthetized open chest dogs, left circumflex coronary artery (LCx) flow, distal LCx perfusion pressure (DCPP), heart rate, and aortic pressure were monitored and regional myocardial ischemia was estimated from ST segment deviation in the epicardial and intramyocardial electrograms obtained from the electrodes located in the area supplied by LCx. In the presence of severe LCx constriction, intracoronary administration of adenosine (0.01 mg/Kg/min) and dipyridamole (0.05 mg/Kg) failed to augment LCx flow and induced further reduction in DCPP without changing systemic hemodynamics. In parallel with these hemodynamic changes, significant ST elevation was observed in the inner layer of the area supplied by the LCx. These results show that subepicardial vasodilation following vasodilatory stimuli can induce transmural flow redistribution and lead to subendocardial ischemia in the presence of severe coronary stenosis.

Adenosine↗