Considerating the origin of the coronary sinus and the oblique vein of the left atrium, both are remnants of the left horn of the embryonal venous sinus. The studies were carried out on 100 human cadaver hearts. The causes of death were not cardiac reasons, no detectable changes in the coronary arteries. In the study, dissections and corrosion technique were used. Heart veins were filled by metacrylan through the coronary sinus. The beginning, the course, the tributaries and the ostium oblique vein of the left atrium to the coronary sinus were investigated. The variability of the length and the venous tributaries and the ostium of the oblique vein of the left atrium were noticed. The variability of the venous tributaries (the dendritic, forked and simple types of the tributaries) was noticed. Four groups of ostium were observed. The ostium oblique vein of the left atrium was situated at the level of: the posterior vein of the left ventricle and also the great cardiac vein, the posterior vein of the left ventricle, the great cardiac vein and the independence ostium.
Despite the variety of modern molecular techniques available, examination of foetal anatomy is still a fundamental part of teratological studies in evaluating the developmental toxicity of xenobiotics or other non-chemical factors. The article presents contemporary methods of embryotoxicity and foetotoxicity assessment. A single alizarin red S and double alcian blue followed by alizarin red S staining, as well as various methods of soft tissue examination are discussed.