Histopathological findings in 151 endomyocardial biopsies

pp 39-57

Abstract

Since the 70's, endomyocardial biopsies were progressively developed.A clear improvement in their procedures and methods has been evident.The assessment of cardiac rejection, myocarditis follow-up, restrictive and dilated cardiomyopathies was incorporated to the medical practice. The endomyocardial biopsy techniques should be secure with low morbidity and non-mortality rates. In this paper,151 endomyocardial biopsies were retrospectively studied between 1978 and 1992(149 from the right ventricle and two from the left).The diagnosis were: 1) dilated cardiomyopathy (n: 46); 2) myocarditis (n: 34); 3)-hypertrophic cardiomyopathy (n: 4); 4)chronic chagasic cardiomyopathy(n: 32); 5) dilatation plus hypertrophy (n: 11);6) dilatation plus fibrosis (n: 4);7) miscellaneous (n: 10); 8) thrombus and insufficient samples (n:10). Dilated cardiomyopathy was characterized by an increase in the myocyte diameters, perinuclear halo, nuclear abnormalities (hypertrophy), attenuation, subendocardial thickening and fibrosis (between 0 % and 37 %); there was no correlationship between the left ventricular ejection fraction and the right ventricular fibrosis fraction. The myocarditis showed necrosis and mononuclear infiltrates (≥ 5 positive leukocyte common antigen cells per 400 X). Chronic chagasic cardiomyopathy showed chronic inflammation, evident necrosis subendocardial sclerosis, severe fibrosis (8.2% to 49%), ≥ 5 positive leukocyte common antigen cells per 400 X, T lymphocytes 32 %,B lymphocytes13 %, mastocytes and eosinophyls <1/400 X. Ultrastructurally, the most important finding was increase in the thickeness of the membranes of myocytes and capillaries. The endomyocardial biopsy and its different techniques of diagnosis (immunohistochemistry, electron microscopy, etc.), should be definitively incorporated as a cardiologic method to forest the knowledge about certain diseases, their diagnosis and as consequence the improving of therapy.