[Myocardial biopsy in morphologic diagnosis of myocarditis]

The term "myocarditis" refers to a process in which leukocytic infiltration is accompanied by cardiac myocyte necrosis or degeneration. It has been recognized largely by using endomyocardial biopsy whose usefulness in the diagnosis of myocarditis is still being verified. Samples of the septal part of the right ventricular wall obtained by venous approach are examined mainly in light microscopy. Despite certain possibilities of using special staining and immunohistochemical methods, hematoxylin and eosin remain basic stains. For the diagnosis of myocarditis it is important to find the signs of the myocyte injury (myocytolysis, vacuolization, disruption) in the contact with inflammatory infiltrates. This has been included in the diagnostic criteria established in Dallas. However both, these criteria and other elements of cardiac biopsy procedure are a subject of increasing doubts and controversies, especially because of incomplete problem's solution of material eligibility and not best clinical--morphological correlation. On the other hand the studies of myocarditis indicate lack of comprehensive approach to its biology. Potential progress depends on the improvement of methods that visualize cardiac myocyte injuries, on the identification of peptides that are markers of genome dysfunctions and on more profound investigation the role of immune cells in the process of myocardial injury and repair.