Light Microscopic Morphological Characteristics and Data on the Ultrastructure of the Cardiomyocytes

Abstract

Many questions regarding the morphology of the cardiovascular system are yet to be answered. In particular, elucidating the core principles of the architectonics of the myocardium is of great importance for the understanding of the exact mechanisms of the cardiac functions and the pathogenic processes which constitute a prerequisite for cardiovascular diseases. A number of contemporary studies reveal the importance of the myocardium in almost every disease -either as a primary pathophysiological unit or as the target of the pathological damage. It has to be stated that the myocardium has a remarkable diagnostic and therapeutic potential. It is comprised of various types of cells -contractile cardiomyocytes of the atria and ventricles, cells of the sinoatrial node and Purkinje fibres, the latter two being part of the conducting system of the heart. The ultrastructural components of these cells include the various structures which ensure cellular contact and communication, the specialised structures of the cellular and the sarcoplasmic membrane and the different elements of the complex cytoskeleton. Furthermore, the orientation of the cardiomyocytes plays a key role not only for the mechanical contraction but also in the electric conduction and the energy metabolism of the cardiac muscle. Studies on the size, alignment and specific characteristics of the cardiomyocytes have the potential to provide a morphological base for the diagnostics of various cardiac pathologies.