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Biomedical subjects

S Beppu

Publications and source records attributed to S Beppu.

At least 127 records · Page 7Linked to original sources
PubMed1981

[Mechanism of the systolic anterior motion of the mitral valve and site of the intraventricular pressure gradient in hypertrophic obstructive cardiomyopathy (author's transl)].

The mechanism of the systolic anterior motion (SAM) of the mitral valve and the relationship between SAM and the intraventricular pressure gradient in hypertrophic cardiomyopathy were analyzed. The subjects were 15 cases, in which SAM was observed on the M-mode echocardiograms. Real-time two-dimensional echocardiography was performed at the time of cardiac catheterization and the measurement of left ventricular pressure was made with observing the spatial relationship between the tip of of the catheter and the surrounding intracardiac structures. There were two modes of the systolic anterior motion of the mitral valve in cases with SAM as follows: (1) The hypertrophied papillary muscle protruded into the left ventricular cavity in systole and it caused the displacement of the chordae tendineae, but also the tips of both anterior and posterior mitral leaflets were anterosuperiorly pulled up by the enlarged papillary muscles and the leaflets seemed apparently to intersect the left ventricular outflow tract (type II). These two types seem to make a continuous spectrum. Seven of the 15 cases examined exhibited type I and 8 cases exhibited type II or the intermediate condition. In the cases of type I, the pressure gradient was noted at the level of the tip of the papillary muscles. The inflow tract and the suprapapillary of the outflow tract exhibited a low pressure, while the apical cavity exhibited a high pressure. It is suggested that the enlarged papillary muscles make the ventricular cavity much more narrowly, resulting in the development of pressure gradient at their level. In the cases of type II, the pressure gradient was noted across the anterior and posterior mitral leaflets perpendicular to the outflow tract (subaortic area). The inflow tract exhibited a high pressure in contrast to that in the cases of type I. It is suggested that the anterosuperiorly pulled anterior and posterior leaflets dam up the ventricular cavity, resulting in the development of pressure gradient across them. Here, it should be emphasized that not only the anterior mitral leaflet, but also the posterior leaflet participates to yield the SAM and the intraventricular pressure gradient.

Adult↗
PubMed1981

[Echocardiographic features of the eustachian valve and its clinical significance (author's transl)].

The detailed informations and clinical significance of the Eustachian valve have not yet been elucidated. Real-time two-dimensional echocardiography has enabled one to investigate the Eustachian valve non-invasively. The valve was usually very small. The larger valve was a few cm in length and moved with heart beat. Its motion was analyzed with M-mode echocardiography. In the cases with sinus rhythm, the valve opened gradually in systole, and opened further in rapid filling phase,. followed by the rapid closing at the time of atrial contraction. In the cases of atrial fibrillation with severe tricuspid regurgitation, the valve remained at the semi-closed position throughout systole and opened in rapid filling phase. In one case of tricuspid regurgitation the valve was observed to flutter in systole. After the surgical repair of the tricuspid valve, systolic opening of the valve was noted, though atrial fibrillation persisted.

Adolescent↗
PubMed1980

Mitral cleft in ostium primum atrial septal defect assessed by cross-sectional echocardiography.

We attempted to detect mitral deformities in ostium primum atrial septal defect using real-time cross-sectional echocardiography. Transverse sections of the anterior mitral leaflet echo were examined in 11 patients with this malformation who subsequently received surgical treatment. The section for observing the transverse view of te anterior leaflet was along the sagittal plane of the body, because of the deformity of the mitral annulus. Each echocardiographic finding was compared with the surgical and angiographic findings. On the echocardiogram, the superior and inferior parts of the anterior mitral leaflet separated into two parts during diastole in all patients with mitral cleft. Thin linear echoes connected the ridges of the cleft and the ventricular septum in seven patients in whom the accessory chordae at that area were revealed at surgery. The systolic configuration of the anterior leaflet echo varied among the patients. The severity of the miral regurgitation seemed to relate not only to the size of the cleft but also to the systolic configuration of the anterior mitral leaflet. After surgery, diastolic separation of the anterior leaflet echo was no longer observed. However, the abnormal systolic configuration of the anterior leaflet was unchanged.

Adolescent↗
PubMed1980

Angiographic volume estimation of right ventricle. Re-evaluation of the previous methods.

Previous angiographic methods for volume estimation of the right ventricle were re-evaluated by ten cast studies as far as the positions of the right ventricular casts were concerned. The spatial orientation of the right ventricular chamber cavity varies clockwise or counterclockwise, in the normal heart. For right ventricular volume estimation, it is important to analyze the right ventricular casts with rotated positions. The casts were studied by biplane cineangiocardiograms with four clockwise rotated positions, which were 0 degrees, 30 degrees, 40 degrees, 45 degrees, and 60 degrees. Simpson's rule and the area-length methods were used for angiocardiographic determination of the right ventricular volume. In four positions, four linear regression equations comparing true volumes with calculated volumes had similar values to each other in the two methods. Regression equation comparing true volumes with calculated volumes which contained a total of 40 casts in four positions, yielded a high correlation coefficient (r = +0.98, p less than 0.001) and small errors in both Simpson's rule and the area-length methods. This study indicates that the right ventricular chamber volume can be accurately estimated with only one regression equation from biplane cineangiocardiograms, even when the right ventricular cavity would have been rotated clockwise or counterclockwise.

Adolescent↗
PubMed1979

Characteristics of ventricular function in single ventricle.

Funtional characteristics of the single ventricle were studied by means of biplane angiocardiography in 34 patients. Group 1 consisted of 14 patients with normal or increased pulmonary vascular marking on chest film and no pulmonary stenosis. Group 2 included 20 patients with severe angiographic pulmonary stenosis and decreased pulmonary vascular marking. Ventricular volume parameters were calculated according to Simpson's rule and were compared with normal values. The sum of the normal left and right ventricular volumes was assumed to be 100%. In group 1, ventricular end-diastolic volumes averaged 143 +/- 11% and were significantly (p less than 0.001) larger than end-diastolic volumes in group 2 (81 +/- 4%). The presence or absence of severe pulmonary stenosis affecting pulmonary blood flow was a main factor regulating the ventricular chamber size in single ventricle. In both groups, the ejection fraction of a single ventricle was significantly lower than that of a normal left or right ventricle. Ventricular size and function in patients with a single ventricle should be carefully assessed before ventricular septation surgery.

Angiocardiography↗
PubMed1976

Diagnosis of endocardial cushion defect with cross-sectional and M-mode scanning echocardiography. Differentiation from secundum atrial septal defect.

Twelve cases of endocardial cushion defect were studied before and after operation with ultrasono-cardiotomography (tomography) cross-sectional echocardiography, two-dimensional echocardiography, B-scan echocardiography) and M-mode scan along a horizontal section of the heart. For comparison, 20 healthy subjects, 18 cases of mitral valvular disease, 4 cases of congestive cardiomyopathy, 1 case of partial anomalous pulmonary venous drainage, and 25 cases of atrial septal defect of secundum type were also examined with the same technique. In cases without cardiac malformation, the echo of the anterior mitral valve was usually continuous medially with that of the interatrial septum in the horizontal plane at the level of the membranous septum. This feature was clearly recorded in all cases with right heart enlargement. In ostium secundum atrial septal defect the echo of the anterior mitral valve continued into that of the interatrial septum. An echo interruption was shown, indicating the defect itself to be in the middle part of the interatrial septum. In all the cases of endocardial cushion defect which we examined discontinuity was shown between the echo of the anterior mitral valve and that of the interatrial septum. This discontinuity was interpreted as indicating the defect itself. The mitral valve ring echo was close to the basal end of that of the interventricular septum, possibly reflecting an abnormal attachment of the mitral valve. In all cases, after operation, the echo of the artificial interatrial septum was recorded, continuous with that of the anterior mitral valve. The features of the echocardiographic sweep from the anterior mitral valve to the interatrial septum were thus different in the three groups. These echocardiographic differences are thought to correspond to the anatomical differences between the normal, atrial septal defect of secundum type, and endocardial cushion defect, and are essential features differentiating them from each other.

Adolescent↗
PubMed1976

Echocardiography diagnosis of ruptured aneurysm of sinus of Valsalva. Report of two cases.

Echocardiographic features of two cases of ruptured congenital aneurysm of Valsalva sinus with (case1) and without (case 2) a supracristal ventricular defect were studied before and after surgery by standard echocardiography. M-mode scan and two-dimensional echocardiography. Discontinuity was observed in the echo from the aneurysm wall of the Valsalva sinus in case 1 with ruptured aneurysm, but was not observed in a similar case of unruptured aneurysm. Herniation of the right coronary cusp of the aortic valve into the right ventricular outflow tract was also observed in case 1. After surgical correction the echo from the aneurysm wall and from the herniated right coronary cusp of the aortic valve disappeared. Discontinuity in the echo from the anterior aortic wall and the interventricular septum also disappeared. In case 2, discontinuity in the echo from the anterior aortic wall, and tricuspid flutter with an abnormally low early diastolic peak were observed. These abnormalities disappeared after surgery. The ability of echocardiography to detect ruptured Valsalva aneurysm is discussed.

Adult↗
PubMed1975

An unusual pattern of the mitral echocardiogram observed in cases of congestive cardiomyopathy and other myocardial diseases.

(1) Narrowness of the early-diastolic and presystolic peaks on the echo curve of the anterior mitral leaflet and an abnormal step formation at the middle or higher level on the descending limb of the presystolic peak were observed in 7 cases with congestive cardiomyopathy or myocardial fibrosis, 1 case with myocardial infarction, and 1 case with cardiomyopathy due to progressive muscular dystrophy. (2) This abnormal pattern is considered to be closely related to the myocardial condition in the above-mentioned diseases. (3) Probable mechanisms for this pattern formation are considered as follows: (i) a sudden reduction of distensibility of the left ventricle after filling of the ventricle over a certain limit near full-filling, and impaired ventricular contractility, (ii) restriction in the mobility of the mitral valve and its chardae due to thier inability to adapt themselves to a developed dilatation of the left ventricle. (4) A similar presystolic step formation on the echo curve of the anterior mitral leaflet was observed in 3 of 25 cases of hypertrophic cardiomyopathy of Goodwin's sense. Differences between the myocardial state in congestive cardiomyopathy or in similar myocardial diseases and that in hypertrophic cardiomyopathy were also discussed.

Adolescent↗
PubMedDate not supplied

Pulsed Doppler echocardiography in the assessment of tricuspid regurgitation.

Pulsed Doppler echocardiography is a noninvasive method with high sensitivity and specificity for the assessment of tricuspid regurgitation. In patients with tricuspid regurgitation, pansystolic unusual Doppler signals are detected in the right atrial cavity, which are interpreted as tricuspid regurgitant flow signals. They distributed in a spindle-shaped area from the tricuspid orifice toward the right atrial posterior wall in parallel with the interatrial septum. The orientation of the range where the regurgitant Doppler signals are detected in the right atrial cavity shows the direction of the regurgitant jet. However, such a result is determined mainly in patients with functional tricuspid regurgitation. In regard to patients with organic tricuspid lesion, different considerations may be necessary. Semiquantitative grading of the severity of regurgitation is possible, based on the distance covered by the regurgitant signals from the tricuspid orifice. Tricuspid regurgitation is demonstrated also by contrast echocardiography. The severity is graded based on the distance reached by regurgitant curvilinear contrast echoes from the tricuspid valve in the M-mode echocardiography. If the ultrasound beam is adequately directed through the tricuspid orifice, the grade estimated by the contrast echoes are well correlated with that by the Doppler. However, if the M-mode is performed without the guide by the two-dimensional image, it may miss the most adequate beam direction for the observation, resulting in underestimating severity. The influences of tricuspid regurgitation are generally seen in the flow pattern of the major veins. However, they are more sharply reflected by the flow condition in the right atrial cavity than by the flows patterns in the major veins.

Blood Flow Velocity↗