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J Yoshikawa

Publications and source records attributed to J Yoshikawa.

At least 343 records · Page 19Linked to original sources
PubMed1987

Age-related valvular regurgitation: a study by pulsed Doppler echocardiography.

To assess the prevalence of valvular regurgitation in the aged, we studied 176 apparently healthy volunteers with no history or physical evidence of cardiac abnormality. Their ages ranged from 40 to 90 (66 +/- 14, mean +/- SD) years. We examined these subjects by pulsed Doppler echocardiography combined with two-dimensional echocardiography to determine the prevalence of valvular regurgitation. Regurgitation began to appear in subjects in their fifties, increasing in prevalence with advancing age (r = .81, p less than .001), and was documented in all over age 80. Similarly, regurgitation involving more than one valve appeared in those 60 years and older, and was very common (89%) in subjects in their eighties. With each type of valvular regurgitation, the prevalence of each type of regurgitation increased with aging, but this tendency was most prominent for aortic regurgitation. We conclude that (1) single or multivalvular regurgitation as detected by pulsed Doppler echocardiography is very common in the aged and may be considered a normal finding in the absence of other evidence of heart disease, and (2) the high prevalence of regurgitation in the aged must be taken into account when Doppler examinations are being performed.

Adult↗
PubMed1987

Focal fatty change of the liver adjacent to the falciform ligament: CT and sonographic findings in five surgically confirmed cases.

Five cases of surgically confirmed focal fatty infiltration of the liver were detected by CT and sonography. In all five cases, the abnormality was located at the anterolateral edge of the medial segment of the liver. It was seen as a small area of low attenuation adjacent to the falciform ligament on CT and as an echogenic area next to the ligamentum teres on sonography. Dynamic CT performed during infusion of contrast medium via the superior mesenteric artery (arterial portography) showed portal blood flow within the lesion and was useful for excluding the presence of a hepatic tumor. Focal fatty infiltration of the liver adjacent to the falciform ligament constitutes a diagnostic pitfall on CT and sonography.

Fatty Liver↗
PubMed1987

[Echocardiographic characteristics and clinical significance of the spontaneous contrast echoes].

Spontaneous echocardiographic contrast is caused by increased ultrasonic density in the cardiac chambers or great vessels, or both, with the characteristic flow pattern of blood, but in the absence of any intravascular injections. This study demonstrated the clinical features and characteristics of the echocardiographic findings of eight patients with spontaneous contrast echoes. Spontaneous contrast echoes were observed in the right heart in five patients, and in the left heart in two. In one patient spontaneous contrast echoes were observed in the right and left heart. All six patients with spontaneous contrast echoes in the right heart had impaired liver function. In these patients, we observed that spontaneous contrast reaching the heart via the hepatic vein on two-dimensional echocardiography. In one patient with atrial septal defect, these contrast echoes were also recognized in the superior mesenteric vein and portal vein. Since capillary beds normally remove ultrasound contrast, the failure of this function suggests porta-systemic shunting in or around the liver. All three patients with spontaneous contrast echoes in the left heart had prosthetic valve dysfunction including paravalvular or transvalvular regurgitation, and consequent hemolysis. Under these conditions, water-vapor bubbles may be formed because of an exhaust pressure decrease due to the Bernoulli effect, or gases may be released from erythrocytes during hemolysis. These water-vapor bubbles or gases could be the cause of spontaneous contrast echoes in the left heart. In conclusion, spontaneous contrast echoes in the right heart are produced by gas absorbed from the intestine because of porta-systemic shunting. The cause of spontaneous left-sided heart echo contrast may be related to prosthetic valve regurgitation, and consequently to hemolysis.

Adult↗
PubMed1986

Therapeutic hepatic vein angioplasty for Budd-Chiari syndrome.

The authors report a case of Budd-Chiari syndrome treated by percutaneous transluminal angioplasty (PTA). In this case, the occlusion of three major hepatic veins with a big collateral to the inferior vena cava via the right inferior hepatic vein (RIHV) and stenosis of the ostium of RIHV were seen. We performed successful PTA of this stenosis.

Angioplasty, Balloon↗
PubMed1986

[Mechanical and electrocardiographic sequence of coronary artery occlusion: an echocardiographic study during coronary angioplasty].

The detection of regional myocardial dysfunction due to acute ischemic event has been limited almost entirely to experimental animal models. In human subjects, it has been limited to the observations during spontaneously-occurring or exercise-induced ischemic events. Recently, percutaneous transluminal coronary angioplasty (PTCA) provides an opportunity to study such dysfunction as the result of repeated interruptions of coronary blood flow. Echocardiograms and electrocardiograms were simultaneously recorded immediately before, during, and after 21 episodes of complete interruptions of coronary blood flow by PTCA in 11 patients. No patient had asynergy of the left ventricle either by two-dimensional echocardiography (2DE) or angiography. All patients had isolated single coronary artery stenosis including the left anterior descending artery in nine, left circumflex artery in one and right coronary artery in one. Recordings of M-mode and 2DE were successfully obtained in 10 patients. After balloon inflation, regional asynergy in the distribution of the instrumented coronary artery appeared in all 10 patients. Hypokinesis developed 9 +/- 3 (means +/- SD) sec after balloon inflation and progressed rapidly to akinesis or dyskinesis. At the same time, decreased systolic thickening of the left ventricular wall appeared in some patients in relation to the development of regional asynergy. However, systolic thinning of the left ventricular wall was not noted in all. The regional asynergy preceded ischemic electrocardiographic changes and had no relation to chest pain. Left ventricular wall motion began to normalize 12 +/- 3 sec after balloon deflation. Thereafter, transient hyperkinesis of the left ventricle developed. The first ischemic electrocardiographic change was a negative U wave which appeared 13 +/- 7 sec after coronary occlusion and remained 3 to 4 sec. Tall T waves were recorded at 28 +/- 12 sec and significant ST elevations developed 31 +/- 11 sec, after balloon inflation. These electrocardiographic changes invariably occurred only after the onset of wall motion abnormalities. Normalization of T waves was recognized at 17 +/- 16 sec and ST segment deviation were no longer present at 18 +/- 10 sec, after reperfusion. These electrocardiographic changes also preceded normalization of regional myocardial dysfunction. In conclusion, left ventricular wall motion abnormalities after coronary occlusion invariably precede the electrocardiographic changes, and begin to normalize after reperfusion prior to the electrocardiographic recovery.

Adult↗
PubMed1986

[Non-rheumatic multivalvular regurgitation in an older population: a pulsed Doppler echocardiographic study].

To assess the incidence of valvular regurgitation, 180 patients more than 40 years of age without cardiac symptoms were studied by pulsed Doppler echocardiography. The 180 patients were categorized by age as group 1, 40 to 49 years; group 2, 50 to 59 years; group 3, 60 to 69 years; group 4, 70 to 79 years; and group 5, more than 80 years of age. The incidence of valvular regurgitant flow signals increased significantly with age. Multivalvular regurgitation were often detected in groups 4 and 5. Furthermore, acoustically silent regurgitation at each valve was frequently noted (71 of 85 cases with valvular regurgitant flow signal: 84%). Mitral valve prolapse was diagnosed by two-dimensional echocardiography in 27 patients, but a mid-systolic click or pansystolic murmur with late-systolic accentuation was not noted. In conclusion, valvular regurgitations were common in the aged who lacked auscultatory findings.

Adult↗
PubMed1986

[Value of right ventricular and atrial collapse in identifying cardiac tamponade].

Collapse of the right ventricle and right and left atria is observed in cardiac tamponade. To assess the diagnostic value of each collapse component in identifying cardiac tamponade, two-dimensional and M-mode echocardiograms were recorded simultaneously with the measurement of intrapericardial pressure in five patients as they underwent pericardiocentesis. Before pericardiocentesis, each patient had evidence of right ventricular and right atrial collapse. In addition, left atrial collapse was observed in four patients. During pericardiocentesis, left atrial collapse initially resolved accompanied by a drop in pressure in the pericardial sac. Continuous drainage of pericardial effusion resulted in significant symptomatic improvement and the cessation of paradoxical pulse at the point of resolution of right ventricular collapse. However, right atrial collapse persisted after resolution of right ventricular collapse, but it was absent when pericardiocentesis was completed. Injection of saline solution with heparin into the pericardial sac for cleansing initially caused right atrial collapse, while right ventricular collapse developed with the appearance of cardiac tamponade. In one patient, the simultaneous recording of right ventricular and intrapericardial pressures and two-dimensional echocardiograms demonstrated that right ventricular collapse occurred early in diastole, when intrapericardial pressure exceeded right ventricular pressure. In conclusion, right ventricular collapse is the most reliable sign of cardiac tamponade. Right atrial collapse occurs in the early stage of cardiac tamponade. Left atrial collapse appears very late in the course of hemodynamic deterioration due to cardiac tamponade.

Adult↗
PubMed1986

[Comments on the diagnostic criteria of mitral valve prolapse].

Two-dimensional echocardiography has been the reference standard for establishing the clinical diagnosis of mitral valve prolapse. Superior systolic displacement of the mitral leaflets, however, is not necessary abnormal. Whether and at what point leaflet displacement uniquely describes a pathologic process should not be accepted without defining the pattern of normal mitral leaflet motion. One should combine informations from phonocardiograms, Doppler color flow mapping and two-dimensional echocardiograms in an effort to avoid the artifice of using two-dimensional echocardiography as a categoric reference standard and to establish new clinical guidline or criteria that distinguish pathologic mitral valve prolapse from normal superior systolic displacement of the mitral leaflets. Mitral valve prolapse is a dynamic disease that results in varying clinical and morphologic presentations depending upon the degree of structural abnormality. Therefore, clinical and morphologic studies are required in not only severely symptomatic patients but also perfectly asymptomatic patients.

Echocardiography↗
PubMed1985

[Functional transvalvular regurgitation in patients with Björk-Shiley aortic valves: a pulsed Doppler echocardiographic study].

It is well known that a small amount of regurgitation occurs through Björk-Shiley valves. Obviously, this functional regurgitation is related to the construction of the Björk-Shiley valve, wherein the disc does not overlap the ring, but fits within its orifice, leaving a minimal space between the edge of the disc and the ring. The aim of this study was to evaluate the clinical significance of regurgitation in patients having Björk-Shiley valves in the aortic position by pulsed Doppler echocardiography. The study group consisted of 46 patients with normally functioning valves and five patients with malfunctioning valves. Valve dysfunction resulted from paravalvular regurgitation in three, and thrombosed valves in two (confirmed by surgery and angiography). Using pulsed Doppler echocardiography, aortic regurgitation was observed in 29 of the 46 normally functioning Björk-Shiley aortic valves. Among these, regurgitant flow signals were constantly located in the vicinity of the valve ring in the left ventricular outflow tract. Therefore, these regurgitant flow signals were considered to represent functional regurgitation of the Björk-Shiley valve. Aortography was performed for 11 of the 46 normally functioning Björk-Shiley valves, and there was minimal transvalvular regurgitation in all. In all of the five malfunctioning Björk-Shiley aortic valves, aortic regurgitant flow signals were detected by pulsed Doppler echocardiography, and the maximal distance of the regurgitant flow signals from the Björk-Shiley valve ring was more than 0.5 cm. However, it was difficult to differentiate transvalvular regurgitation from paravalvular regurgitation using pulsed Doppler technique alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Aortic Valve↗
PubMed1985

[Tricuspid regurgitation evaluated by Doppler hepatic vein flow patterns].

Hepatic vein flow can be reliably measured because Doppler sampling volumes are easily oriented parallel with the course of the hepatic vein. In this study, the relationship between the Doppler signal in the hepatic vein and the external jugular vein pulse was evaluated, and the contribution of the Doppler echocardiography to the quantitative diagnosis of tricuspid regurgitation was also assessed. The subjects consisted of five healthy persons, four patients with lone atrial fibrillation, 27 patients who underwent cardiac surgery, and 34 patients with tricuspid regurgitation. The severity of the regurgitation was judged by right ventriculography and inferior caval angiography. The pattern of the Doppler hepatic vein flow mimicked that of the jugular phlebogram in each patient. The normal hepatic vein flow consisted of two forward flows toward the heart; one in systole; the other, in diastole, and one retrograde flow toward the liver during atrial contraction. In patients with lone atrial fibrillation, a systolic backward flow toward the liver or a decrease in the systolic forward flow was observed, though there was no tricuspid regurgitation. In patients who had cardiac surgery, a systolic backward flow toward the liver or a decrease in the systolic forward flow was usual. However, a prominent systolic backward flow toward the liver was observed in patients with severe tricuspid regurgitation, and a decreased systolic forward flow toward the heart was observed in patients with moderate tricuspid regurgitation in sinus rhythm. We concluded that Doppler measurement of hepatic vein flow does not contribute to the diagnosis of tricuspid regurgitation in the presence of atrial fibrillation or in postoperative conditions, but that it is useful in identifying severe tricuspid regurgitation.

Coronary Artery Bypass↗
PubMed1985

[An intermittent mid-diastolic musical murmur indicating aortic regurgitation: report of a case].

An unusual mid-diastolic musical murmur developed soon after cardiac catheterization of a 55-year-old man with mitral stenosis. His physical findings consisted of an accentuated first heart sound, an opening snap and a grade 3/6 mid-diastolic rumbling murmur. No early diastolic murmur was audible. However, soon after cardiac catheterization, a mid-diastolic "cooing" murmur at a frequency of 200 cycles/sec developed. This murmur resolved with the patient in the sitting position, or by leg raising. With Valsalva or Müller maneuvers this murmur was abolished transiently, and it disappeared on administering either amyl nitrite or methoxamine. Echocardiography revealed early diastolic vibrations in the aortic valve. Pulsed Doppler echocardiograms revealed harmonic signals of the aortic cusp at a fundamental frequency of 200 cycles/sec. These harmonic signals could be recorded only in mid-diastole. The frequency patterns of the murmur and the Doppler signals were identical; therefore, the murmur was judged to be produced by aortic valve vibrations. Furthermore, resonance of cardiac structures which accentuate the murmur might be related to the occurrence of this murmur. Pulsed Doppler echocardiography is helpful in identifying the site of origin of this musical murmur.

Aortic Valve Insufficiency↗
PubMed1985

[Two-dimensional echocardiography in diagnosing the region of myocardial infarction: a comparative study by several independent examiners].

The efficacy of two-dimensional echocardiography in diagnosing the localization of myocardial infarction (MI) was studied by comparing the echocardiographic and pathological findings of 28 patients having MI. The ventricular wall was divided into 18 segments including three segments of the right ventricular wall. The regional wall motion abnormalities for each of the 504 segments were diagnosed by visual assessment. The echocardiographic recordings were reviewed individually by four examiners using the same protocol to assess the interobserver's variation. The receiver operating characteristics (ROC) curves differed by examiners. However, when the subjects were limited to anterior MI patients, the ROC curves established by the echo-trained physicians did not differ significantly. It was concluded that the echocardiographic diagnosis of regional wall motion by visual assessment has universal validity. Individual differences are thought mainly to depend on the sites of infarction. Sensitivities for detecting transmural (TM), non-transmural (non-TM) infarcted segments and intact segments were 90, 70 and 70%, respectively. Most of the underestimated TM or overestimated intact segments corresponded to the sites adjacent to MI. As the unexpectedly misdiagnosed segments, the mimic inward motion of the inferior wall drawn by the intact anteroapical wall was observed in a inferior MI patient, or the mimic anterior motion of the anteroapical wall by a swinging motion of the heart, or the paradoxical motion of the interventricular septum was observed in a right ventricular MI case. In the two third of the overestimated non-TM segments, it was considered that the wall motion was affected by the myocardial ischemia, which was not revealed by pathological examination. The underestimated non-TM segments located adjacent to the intact segments or opposite to the severely ischemic segments. From the echocardiographic viewpoint, nearly 90% of segments showing akinetic or dyskinetic motion had MI. However, one third of segments diagnosed as normal were actually MI segments.

Aged↗