Anatomy, histology, and electron microscopy of the cardiac conduction system. Current views and new data: review

The review provides a current view of the anatomy, histology, immunohistochemistry, electron microscopy, and electron immunocytochemistry of the cardiac conduction system (CCS) based on literature data and the author's own research over more than 30 years. The article describes a new specialized x-structure of the CCS, discovered by the author and published in 2014, and another type of cells that are part of the sinus and atrioventricular nodes — telocytes, capable of generating and conducting an electrical impulse. Based on layer-by-layer dissection and serial histological sections performed on more than 400 adult hearts, the topographic anatomy of the atrial muscular framework is given. The article also describes the atrial innervation.