Search PubMed⌕ Search

Biomedical subjects

M Hiroe

Publications and source records attributed to M Hiroe.

At least 199 records · Page 11Linked to original sources
PubMed1985

On the interstitial fibrotic changes in acute and convalescent myocarditis obtained by serial endomyocardial biopsy.

In order to determine the characteristics of the interstitial fibrotic change of the myocardium in cases with viral or idiopathic myocarditis, right ventricular endomyocardial biopsy findings in 9 cases where serial endomyocardial biopsy had been performed at the acute (5-10 days after the onset of the disease), subacute (11-21 days) and convalescent stages (22-167 days) and in 1 case at the acute stage were analyzed. They were then compared with right ventricular endomyocardial biopsy findings from 58 cases with chronic right ventricular overloading and which were of various kinds of congenital and valvular heart diseases. The following results were obtained: Interstitial fibrosis was seen at the acute stage along with an increase in fibroblasts, macrophages and lymphocytes. An analysis of the interstitial changes revealed that, at the acute stage, thin collagenous fibers were prominent as well as interstitial edema and at the convalescent stage, the edema became less prominent and instead, thick collagenous fibers increased. Comparison with the 58 cases with chronic right ventricular overloading revealed that diffuse and/or subendocardial fibrosis and endocardial thickening were more frequent and statistically more significant in cases with myocarditis.

Acute Disease↗
PubMed1985

Improved myocardial ischemia and left ventricular function during exercise after successful percutaneous transluminal coronary angioplasty.

Percutaneous transluminal coronary angioplasty (PTCA) was performed in 42 patients with effort angina, 28 (67%) of them underwent successful angioplasty. Treadmill exercise testing, thallium-201 myocardial scintigraphy and radionuclide ventriculography were performed before and after PTCA for evaluation of the improvement of myocardial ischemia and left ventricular function at rest and during exercise. The average exercise duration by treadmill testing in 14 successful cases increased from 14 +/- 4 (mean +/- S.D.) to 16 +/- 2 minutes (p less than 0.05). Sixteen of 28 the patients were studied by thallium-201 myocardial scintigraphy. Before PTCA, regions of decreased thallium-201 uptake after exercise were observed in 12 of the 16 patients. After angioplasty, no distinct defects were recognizable in 9 of the 12 patients, and in the remaining three, a significant decrease in defects was recognized. Fifteen of the 28 patients were studied by radionuclide ventriculography. The mean ejection fraction was 61 +/- 5% at rest and 56 +/- 11% during exercise (N.S.) before PTCA. After angioplasty, the ejection fraction was unchanged at rest (61 +/- 5 to 62 +/- 4%), but increased significantly during exercise (62 +/- 4 to 74 +/- 4%, p less than 0.001). In conclusion, left ventricular function was improved by successful PTCA due to improvement of myocardial ischemia. The long term results require further study.

Adult↗
PubMed1985

[Do giant negative T waves represent apical hypertrophic cardiomyopathy? Left ventriculographic and cardiac biopsy studies].

Whether giant negative T waves (GNT) of 1 mV or greater represent the electrocardiographic characteristics of idiopathic cardiomyopathy, particularly apical hypertrophic cardiomyopathy, is controversial. To clarify this point, a comparative study was conducted for 57 persons with GNT (GNT+ group) and 57 persons of hypertrophic cardiomyopathy with either asymmetric septal hypertrophy or diffuse hypertrophy of the ventricular wall in the absence of GNT (GNT- group). Patients with cerebral vascular accidents, myocardial infarctions, valvular heart disease, myopericarditis, and implanted pacemakers were excluded from the study because these patients' ECGs may show GNT. Left ventriculograms were investigated at end-diastole in the right anterior oblique projection. The GNT+ group showed a spade-like configuration indicating a marked reduction in the lumen of the apical cavity in 25 cases (43.9%); a kidney or banana-like configuration indicating the inferior wall bulging into the left ventricular cavity in its mid-zone in eight cases (14.0%), and an oval configuration which indicated no deformity of the left ventricular cavity in 24 (42.1%). The spade-like configuration was also seen in four cases (7.0%) of the GNT- group. A study of ventricular wall thicknesses based on left ventriculography showed that 25.5% of cases with GNT did not have concomitant apical hypertrophy. Generally, the GNT+ group cases had a significantly thicker anterior left ventricular wall and apical hypertrophy compared to the GNT- group. The hypertrophic states of the apical wall and anterior wall of the left ventricle correlated well. The GNT+ group included a significantly larger percentage of patients who were middle aged and older than did the GNT- group, and the frequency of accompanying hypertension was significantly higher in the former. The confirmed or suspected familial occurrence of cardiomyopathy (CM) was observed in 32 cases (56.1%) of the GNT- group, and in 18 cases (31.6%) of the GNT+ group, i.e., the incidence was significantly lower in the GNT+ group. In an endomyocardial biopsy study, 40 cases (70.1%) of HCM without GNT had bizarre myocardial hypertrophy with disorganization (BMHD). The incidence of BMHD in the GNT+ group was 21/57 (36.8%)-significantly lower than in the GNT- group. In the GNT- group, there was no significant difference in the incidence of BMHD between relatively young and old patients or between patients with and without accompanying hypertension; whereas, in the GNT+ group, it was significantly lower among those with accompanying hypertension and in older patients than in those without accompanying hypertension and in younger patients.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1984

Effects of intravenous verapamil on the haemodynamic response to exercise in patients with angina pectoris.

The effects of intravenous Verapamil (V) on exercise haemodynamics and ventricular function were compared in 13 patients with stable effort angina. Intravascular pressures, thermodilution cardiac output and radionuclide ejection fraction were measured simultaneously at rest and during exercise. At rest Verapamil produced systemic vasodilation. During exercise at identical workloads compared to control, Verapamil increased cardiac index (CI) and decreased AVO2 difference. Pulmonary artery wedge pressure was lower. Ejection fraction was higher (control-55 +/- 11% vs V-64 +/- 11%) as the disproportionate increase in end systolic volume relative to the end diastolic volume was prevented. Verapamil is effective in exercise induced angina and alters haemodynamics primarily through its vasodilating properties associated with an increased CI.

Adult↗
PubMed1984

Histopathological findings of acute and convalescent myocarditis obtained by serial endomyocardial biopsy.

Serial endomyocardial biopsy findings in 20 cases with acute myocarditis of possible viral origin were analyzed. The histopathological findings were analyzed during the acute (0-10 days after the onset: 8.3 +/- 1.9 days; 6 cases), the subacute (11-21 days: 18.2 +/- 2.2 days, 6 cases), and the convalescent stages (22-167 days: 54.5 +/- 45.4 days; 8 cases). The incidence and severity of various changes of the cardiac myocytes and interstitial changes were analyzed and compared at each stage of the disease. In the acute stage, interstitial cell infiltrations were composed of fibroblasts, macrophages and lymphocytes, taken out in descending order. In the convalescent stage, interstitial cell infiltration showed a marked increase and was replaced by fibrocytes. In the subacute stage, transitional changes between the acute and convalescent stages were observable. A controlled myocardium in 21 cases with myocardial infarction which were compared at various stages revealed that in the acute stage, neutrophils were most prominent, and in the subacute and convalescent stages, macrophages were most prominent and plasma cells were most often observed. The time course changes of the histopathological findings in acute myocarditis were as follows: In the acute stage, Interstitial cell infiltration which is composed of fibroblasts, macrophages and lymphocytes, fragmentation of the muscle bundles, myocytolytic changes, swelling and scarcity of the cytoplasm and swelling of nuclei, variation in size of the myocytes, disarrangement of the muscle bundles, interstitial edema, increased glycogen deposition in the myocytes, abnormal branching of the myocytes, and interstitial fibrosis were observable. In the convalescent stage, most of the above described findings were still observable except for the myocytolytic change, swelling of myocytes and interstitial edema.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMed1984

Ultrastructural features of the endomyocardium in patients with eosinophilic heart disease. An endomyocardial biopsy study.

In a series of studies with endomyocardial biopsy, 7 adult cases with cardiac disease and eosinophilia were studied clinically and electro-microscopy. Degranulation of the eosinophils in the peripheral blood was observed ultrastructurally in 3 of the 4 cases studied. The clinical expression of the 7 patients were, restrictive cardiomyopathy in 2, dilated cardiomyopathy in 2 and sick sinus syndrome in 1 and others in 2. Endocardial thickening was observed in 5 cases, one of whom showed a marked cellular infiltration with macrophages, plasma cells, lymphocytes and mast cells. One other case showed cell debris of degranulated eosinophils. Degeneration of the myocytes was manifested by an increase in Z-bands of the myofibrils as well as streaming (1 case), disarrangement of the myofibrils, and mitochondrial change (1 case) which was characterized by giant mitochondria (1 case) as well as by a numerical increase in mitochondria. Increase of atrial granules and mitochondria in a right atrial biopsy of a case with sick sinus syndrome was noteworthy. Basal lamina layering of the capillaries of the myocardium and pyknosis of an endothelial cell cytoplasm were also noted in each case. These observations may reveal that various disease processes are taking place in the endocardium and adjacent myocardium.

Adult↗
PubMed1984

Effect of atrial pacing on phase analysis in patients with the Wolff-Parkinson-White syndrome.

Phase analysis of ECG-gated radionuclide ventriculography was performed during sinus rhythm and atrial pacing for 11 patients with the Wolff-Parkinson-White (WPW) syndrome. During sinus rhythm, phase analysis demonstrated abnormal early-emptying segments reflecting preexcitation in six of the 11 patients. In the remaining five patients, the precise site of abnormal early-emptying could not be detected. Atrial pacing increased the degree of pre-excitation, and abnormal early-emptying segments became clear in all patients. Our study demonstrated the utility of atrial pacing in performing phase analysis for patients with the WPW syndrome. Seven patients had abnormal early-emptying segments; four of them with ECG type A, in the left ventricle, and three of them with ECG type B, in the right ventricle. These results were consistent with results of the body surface and electrophysiologic mapping. In patients with posterior septal accessory pathways, phase analysis suggested probable laterality of the accessory pathway.

Adolescent↗
PubMed1983

Ventriculographic findings in the convalescent stage in eleven cases with acute myocarditis.

In order to clarify the sequelae of 11 patients who suffered from acute myocarditis of viral origin and were diagnosed by endomyocardial biopsy in the early and the convalescent stage of the disease, left ventriculograms were obtained from 17 to 167 (46.5 +/- 41.2, mean +/- SD) days after the onset of the disease were analyzed. The data were compared with the biopsy findings in the convalescent stage. The mean left ventricular ejection fraction (LVEF) was 57.5 +/- 10.8% and in 3 cases the LVEF was less than 50%. In 2 cases, apparent asyneresis was observed. In all cases coronary arteriographic findings did not show significant stenosis. It is concluded that after viral myocarditis, increase in left ventricular end-diastolic volume, depressed ejection fraction and asyneresis occur in some cases and it can be said that a development from myocarditis to dilated cardiomyopathy occurs.

Acute Disease↗
PubMed1982

Comparison of thallium-201 scanning in idiopathic dilated cardiomyopathy and severe coronary artery disease.

To determine whether cardiomyopathy could be distinguished from coronary artery disease, we used thallium scanning to study 25 patients with severe left ventricular dysfunction and chronic heart failure. Ten patients had normal coronary arteries and idiopathic cardiomyopathy (ejection fraction 20 +/- 5%), and 15 patients had multivessel coronary disease and left ventricular dysfunction (ejection fraction 25 +/- 6%). The exercise time and maximal heart rate were similar in the two groups. Two patients with cardiomyopathy and 11 with coronary artery disease had a positive exercise ECG (p less than 0.05). Thallium scans showed perfusion defects in all 25 patients. The perfusion defects were complete in nine coronary artery disease patients (60%) and in one patient (10%) with cardiomyopathy (p less than 0.05). Extensive defects involving more than 40% of the left ventricular circumference, the number of segments involved, redistribution on the 4-hour scan, lung uptake and ventricular size were similar in the two groups. Perfusion defects on thallium scanning can occur in patients with idiopathic dilated cardiomyopathy and chronic heart failure. Thallium scanning cannot be reliably used in patients with chronic heart failure to distinguish coronary artery disease from cardiomyopathy unless complete defects are present.

Adult↗
PubMed1982

Long-term follow-up of electrocardiographic findings in patients with acute myocarditis proven by endomyocardial biopsy.

Sixteen cases of acute myocarditis, proven by endomyocardial biopsy, of possible viral origin which were described in a previous paper have been followed up for up to 5 years. The cases were divided into 3 groups according to the electrocardiographic (ECG) patterns: with conduction disturbance at the early stage (Group I, 9 cases), without conduction disturbance (Group II, 4 cases); early death cases in which the follow-up could not be carried out (Group III, 3 cases). In Group I, 2 cases revealed persistent complete A-V block, 4 showed incomplete recovery of right bundle branch and/or fascicular blocks, and 3 showed complete recovery of the ECG abnormalities. In Group II, all 4 cases showed a pseudoinfarction pattern which consisted of abnormal Q waves, poor R wave progression and ST elevation. These findings disappeared during the follow-up period. All patients of Groups I and II are still alive after a follow-up period of up to 5 years.

Acute Disease↗
PubMed1981

Early clinical profiles of cases with histopathologically proven acute idiopathic myocarditis and a proposal for diagnostic criteria.

The early clinical features, primary care, treatment and short-term prognosis in 15 cases of acute myocarditis where diagnostic confirmation was made by endomyocardial biopsy or autopsy were analyzed. Characteristically, idiopathic myocarditis of possible viral etiology revealed preceding symptoms which consisted of flu-like symptoms, i.e., fever, upper respiratory infection (sore throat, cough), myalgia or arthralgia, general malaise, and gastrointestinal disorders (vomiting, anorexia, nausea, abdominal pain and soft stool). A severe cardiac or generalized disease condition may follow. Depending upon the progress of intensive medical and cardiac care, the patients' prognosis is not always poor. Diagnostic criteria based upon our own experience have been constructed as a proposal.

Acute Disease↗