Ricardo Beigelman

Endomyocardial biopsies in chronic chagasic cardiomyopathy. Immunohistochemical and ultrastructural findings.

Mononuclear cellular infiltrates and extensive fibrosis, with or without apical ventricular aneurysms, are the usual morphological findings in chronic chagasic cardiomyopathy. These lesions are thought to be mediated by immune phenomena rather than by continuing parasitic invasion of the heart. In the present report, we correlated clinical, immunohistochemical and ultrastructural findings in 30 endomyocardial biopsies from patients with chronic chagasic cardiomyopathy. In 12 of these biopsies, immunocytochemical techniques were used to identify and count leukocytes (common leukocyte antigen, CLA), T lymphocytes (UCHL-1 antibody) and B lymphocytes (L-26 antibody). The biopsy specimens showed variable degrees of myocardial hypertrophy and mononuclear infiltrates. No tissue forms of trypanosomes were found. The endocardium averaged 24 +/- 12.6 microns (mean +/- SD) in thickness. The mean myocyte diameter was 20 +/- 7.33 microns. The hearts were severely fibrotic containing a mean of 24.1 +/- 12.8% of fibrous tissue (range 8.2-49%), mast cells were scarce. Mononuclear cell infiltrates were found in 25 of the 30 biopsies. In 12 biopsies, immunohistochemical studies showed that the majority of the lymphocytes were T lymphocytes and associated with necrotic or degenerating myocytes. 10 of the 12 biopsy samples showed 5 or more CLA-positive mononuclear cells/high power field. In these 10 patients, T and B lymphocytes represented 32 and 13% of the total mononuclear infiltrating cells, respectively. The remaining cells were monocytes and macrophages.

Are Kinking and Coiling of Carotid Artery Congenital or Acquired

Dolichoarteriopathies consist of tortuosity, kinking, or coiling of the extracranial carotid arteries. Some authors consider these alterations a consequence of atherosclerotic vessel remodeling, while others ascribe them to anatomical variations of embryological origin. The objective was to establish whether carotid dolichoarteriopathies belonged to a congenital origin or to acquired conditions. Color Doppler ultrasonography of neck vessels was performed in 885 participants, whose age ranged from 1-day-old infants to 90-year-old adults. Prevalence of kinking and coiling was evaluated, and it was related to the presence of cardiovascular risk factors. Prevalence of either kinking or coil of carotid arteries showed no increase with age, as it was comparable across all ages; furthermore, frequency of these alterations showed no relationship to cardiovascular risk factors nor to the presence of atheromatous plaques. These findings suggest that carotid dolichoarteriopathies are a result of alterations in embryological development rather than vascular remodeling secondary to aging and/or atherosclerosis.

Effect of vitamins A and E on ischemia-reperfusion damage in rabbit heart

The aim of this study was to test the effect of vitamins A and E in reducing oxyradical effects and myocardial damage after ischemia — reperfusion in the rabbit heart. Oxyradical effects were indirectly assessed by hydroperoxide initiated chemiluminescence and myocardial damage was evaluated by qualitative and quantitative electron microscopy. Left anterior coronary artery was ligated in control and vitamin-treated rabbits for 30 min and then reperfused for 10 min. Rabbits were pretreated with 150 mg vitamin E and 60000 IU vitamin A 24 h before surgery. After 10 min of reperfusion full-thickness needle samples were obtained from five different myocardial areas (three ventricular and two septal areas) and used for the determination of hydroperoxide-initiated chemiluminescence and ultrastructural damage. In the control group, hydroperoxide-initiated chemiluminescence was 18400±500 cpm/mg protein for the non-ischemic and non-reperfused ventricular areas, and 40500±1800 cpm/mg protein for ischemic-reperfused ventricular areas. In the vitamin-treated group, hydroperoxide-initiated chemiluminescence was decreased by 8% in the non ischemic and non reperfused ventricular areas and by 51–75% in the ventricular ischemic and reperfused areas. The two septal areas in the control group gave chemiluminescences of 6800±1200 cpm/mg protein (non ischemic-non reperfused) and 17000±2000 cpm/mg protein (ischemia-reperfusion). In the vitamin-treated group, chemiluminescence decreased by 4 and 58%, respectively.The ischemia-reperfused areas showed extensive edema, margination of nuclear chromatin and swollen mitochondria with disrupted cristae including rupture of the inner and outer mitochondrial membranes. Assessment of mitochondrial damage in electron micrographs by stereological counting and grading indicated 77% of damaged mitochondria. These hearts displayed the early sings of irreversible damage and infarction. Rabbits pretreated with vitamins A and E showed a 18% of damaged mitochondria in the same areas (p<0.001) and relative preservation of myocyte subcellular structures.The results indicated that vitamins A and E reduce hydroperoxide-initiated chemiluminescence and myocardial cell damage during ischemia-reperfusion in the rabbit.

Inapparent myocarditis and sudden death in pediatrics. Diagnosis by immunohistochemical staining

We analyzed the anatomopathological findings in two cases of sudden death related to myocarditis in pediatric patients. Since the diagnosis of myocarditis depends either upon histologic and histochemical techniques or the manner the sample was obtained, we describe a more specific immunohistochemical method to stain samples and more accurately diagnose and qualify cellular lymphoid strains in the inflammatory reaction of the myocardium thus allowing a correct diagnosis of myocarditis.

Beneficial Effects of Cloricromene in Ischemic Reperf used Myocardium

Cloricromene (Clo) has been used to prevent myocardial damage after transient occlusion of the circumflex coronary artery (Cx). Twenty rabbits were injected for 4 days with a single dose of Clo (0.25 mg/kg i.v.) or placebo. On the 5th day, the Cx was occluded, and Clo (6.4 micrograms/kg/min) or placebo was continuously infused. After 50 min, the occlusion was removed and after 20 min of reperfusion, the rabbits were sacrificed. In the placebo group, all rabbits showed marked ST segment changes and severe ischemic arrhythmias (6/10 animals). In 5 of them, ventricular fibrillation was followed by death. In the Clo group smaller ST segment elevations were observed, and in 2 rabbits ventricular fibrillation spontaneously reversed as did ST segment elevations. A significant reduction of the necrotic area was also observed in the Clo group by postmortem examination.

The hypertrophied myocardium and coronary disease. Structural changes in patients submitted to aortocoronary bypass surgery

Seventeen patients with coronary disease submitted to myocardial revascularization were studied. Ten patients had a hypertrophied ventricle, and 7 had normal ventricular mass. Myocardial biopsies were obtained before ischemia and at the time of reperfusion and were assessed for: volume fraction of fibrous tissue, myocyte diameter, morphometric mitochondrial studies and ultrastructural changes. The volume fraction of fibrous tissue in patients with hypertrophied ventricle was 1.9 +/- 0.04, and in patients with normal ventricular mass was 0.9 +/- 0.01 (p less than 0.05). The diameter of the myocyte was 23 +/- 0.3 microns and 18 +/- 1.2 microns for patients with hypertrophied and normal ventricular mass, respectively (p less than 0.01). The value of volumetric density for pre-ischemia samples in patients with a hypertrophied ventricle was 23 +/- 2.2 and in patients with normal ventricular mass was 35 +/- 2.7 (p less than 0.02). Grades 3 and 4 of damaged mitochondria were significantly increased in reperfusion samples from patients with a hypertrophied ventricle compared to pre-ischemia samples. Collagen growth was increased in hypertrophied hearts which were also more sensitive to the ischemia/reperfusion mechanism.

Inusual caso de revascularización espontánea en una paciente con arteriopatía carotídea significativa

Resumen es: La enfermedad grave de las carotidas primitivas y externas es una entidad poco frecuente, que en general ocurre en pacientes con aterosclerosis avanzada....

Tumor del cuerpo carotídeo: Imágenes de dos casos, uno con compresión de la arteria carótida externa

Caso 1: Mujer de 35 años sin antecedentes patológicos. Consultó por masa pulsátil evidente no dolorosa en el lado izquierdo del cuello. A la palpación, aproximadamente 3 cm, se destaca importante soplo sistólico a ese nivel. Se le solicitó eco-Doppler color de los vasos del cuello, que determinó el diagnóstico de tumor del cuerpo carotídeo (TCC) (Figura 1). Caso 2: Mujer de 87 años, hipertensa, con episodios de mareos de duración variable y remisión espontánea, de 6 meses de evolución. Se observó asimetría cervical derecha, palpándose una masa móvil, indolora, de aproximadamente 3 cm de diámetro. La paciente refirió leve sensación de vértigo en el movimiento lateral cervical. En el eco-Doppler de los vasos del cuello se observaron un TCC y disminución del calibre de la arteria carótida externa sin placas ateromatosas en su interior (Figura 2). En ambos casos, las pacientes rechazaron continuar con estudios complementarios. Los TCC son raras neoformaciones de crecimiento lento, hipervascularizados, infrecuentes (0,01% de la población), derivados de células paraganglionares de la cresta neural y representan casi la mitad de todos los paragangliomas. Generalmente son benignos y por lo común se presentan como una masa cervical asintomática, por lo