Heart and vessels. Supplement最新文献

In our series of studies of cardiomyopathy with endomyocardial biopsy in 1500 cases, we have noticed that there were a certain number of patients with arrhythmias and/or conduction disturbance who showed no evidence of hypertrophic or dilated form of caridiomyopathy but showed significant pathology in the biopsy. Significant pathology was determined when the biopsy findings from the right atrium and the right ventricle showed apparent pathology such as interstitial fibrosis, myocyte degeneration, and fragmentation of muscle bundles. Among 226 biopsied patients in whom arrhythmia and/or conduction disturbance were the main clinical feature, 85 patients (38%) demonstrated significant pathology in their biopsy. Familial occurrence was note-worthy among these patients. We propose that these cases should be grouped as nonhypertrophic, nondilated, and nonrestrictive cardiomyopathy, and suggest the term electric disturbance type of cardiomyopathy (ECM).

A case report of patient with cardiac sarcoidosis is presented. Advanced atrioventricular (AV) block and abnormalities of radionuclide imaging were improved by steroid therapy. We stress the effectiveness of steroid therapy together with usefulness of radionuclide techniques.

In patients with acute myocarditis, arrhythmias constitute one of the crucial risk factors for morbidity and mortality. To clarify the incidences and the chronological features of arrhythmias and their correlation with the histopathology of the heart, we conducted continuous electrocardiography in an animal model of viral myocarditis, and light microscopy of the heart with special reference to the conduction system. Forty weanling C3H/He mice were divided into an inoculated group (IG) and a control group (CG), of 20 mice each. IG was injected intraperitoneally with coxsackie B3 virus and CG was injected with virus-free culture medium. Thin electrodes were implanted in their chest walls and connected with an electric impulse transmitting device so that they could move freely. ECGs were recorded continuously without anesthesia up to the 14th postinoculation day. The atrial and ventricular myocardium and the conduction system were studied by light microscopy. In CG, no arrhythmia was noted. In IG, various kinds of arrhythmias were documented. The incidences of the arrhythmia in the 20 mice were: sinus arrest 80%, second or third degree atrioventricular (AV) block 30%, premature atrial complexes 30%, premature ventricular complexes 20%, and ventricular tachycardia 10%. Arrhythmias were usually transient and recurrent, and the majority of them developed between the 6th and 13th day, when the histologic changes of the heart were greatest. There seemed to be a correlation between the kind of arrhythmias and the myocarditic lesions. Mice with sinus arrest or AV block developed histopathologic changes in the sinus node or AV conducting tissue, respectively. In the early stage of myocarditis, no inflammatory changes were apparent in the sinus node in the mice with sinus arrest.

An autopsy case of cardiomyopathy with restrictive physiology associated with subendocardial myocardial necrosis and fibrosis in a seven-year-old child is described. Cardiac catheterization showed high left ventricular end-diastolic pressure with a dip-and-plateau pattern. Macroscopically, marked dilatation with fibroelastosis in both atria and mild dilatation in both ventricles were observed. Histologic examination revealed extensive subendocardial necrosis with marked disorganization of myocardial cells and moderate arteriolosclerosis. We speculate that these extensive myocardial lesions, which contributed to the restrictive hemodynamic changes, could have been induced by anoxia or a Ca2+ transport abnormality of unknown cause.

A ten-year-old male with palpebral edema was proved to have a restrictive hemodynamic pattern by cardiac catheterization. Sequential echocardiographic examination revealed uniformly depressed left ventricular diastolic properties, well-maintained left ventricular systolic function, and a progression of obliterative change of the left ventricular cavity. Myocardial biopsy at 17 years of age disclosed a normal endocardium and marked interstitial fibrosis of the myocardium. Consequently, a decrease of cardiac output and a marked biatrial enlargement have developed in association with persistent atrial fibrillation.

Two cases of juvenile restrictive cardiomyopathy are presented, in which we highlight the useful role of noninvasive diagnostic techniques including the apexcardiogram, echocardiography, and magnetic resonance (MR) imaging.

A 70-year-old woman with active hypereosinophilic myocarditis presented with high fever and heart failure. Repeated right ventricular endomyocardial biopsies and 201-T1 myocardial scans before and after steroid therapy suggested that this treatment reversed the cardiac injury. Patients with hypereosinophilia may die from complications of eosinophilic infiltration and fibrosis in target organs, especially the heart. The findings in this patient suggest that steroids have benefit in this disease, at least in the short term.

To study the pathogenesis of idiopathic ventricular tachycardia with left bundle branch block morphology (LBBB-VT), histopathological findings in 34 patients and adrenergic receptor (AR) density obtained by micro-autoradiography in 11 patients were analyzed, using endomyocardial biopsy samples. According to the ventricular volume, we divided the patients into 3 groups. Group A patients (n = 8) were diagnosed as having arrhythmogenic right ventricular dysplasia (ARVD) showing right ventricular enlargement, group B patients (n = 7) showed decreased left ventricular function and/or enlarged left ventricle, and group C (n = 19) included patients with idiopathic ventricular tachycardia (VT) without enlargement or dysfunction of either ventricle. Histologically, there was a high incidence of significant pathology showing myocardial hypertrophy, degeneration, abnormal branching, and interstitial fibrosis in all groups (group A, 100%; group B, 86%; group C, 56%). There was a higher incidence of fatty tissue infiltration in groups A (100%), B (71%), C (48%) than in the control groups. As for AR, specific grains of alpha 1- and beta-AR were 23.0, and 18.3 (grains/25 x 25 mm square) respectively, in patients with LBBB-VT. The number of alpha 1 grains in patients with LBBB-VT was apparently higher than in the control group, sick sinus syndrome (SSS; 11.2), and the beta-AR density in the LBBB-VT group was the same as in the control group (SSS; 15.4). We concluded that the significant pathology in cases with VT might affect the arrhythmogenic condition. Moreover, these results suggested that the increase in the number of alpha 1-AR might have a great influence in idiopathic VT.

Two cases of dilated cardiomyopathy with incessant supraventricular tachycardia were treated with beta-blockade. Propranolol at a dose of 30 mg per day in combination with diuretics and digitalis decreased atrial rate of tachycardia and the cardiac size in both cases. The careful administration of beta-blockade seems to be one of the choices for the treatment for atrial tachycardia associated with dilated cardiomyopathy.