[Atresia of the right atrioventricular ostium].

Thirteen heart preparations with atresia of the right atrio-ventricular orifice (ARAVO) were examined. The ARAVO implies a congenital heart defect characterized by the lack of direct anatomical contact between the right atrium and the right ventricle, the presence of interatrial passage, the only left atrio-ventricular orifice connecting the left atrium with the only ventricular chamber. As indicated by the results of the study, "the right ventricle" in ARAVO contains no sinus part and, therefore, cannot be regarded as a ventricle. It is a rudimentary chamber. The above data indicate that a heart with one ventricle is the only ventricle. The typical findings in the ventricular (infundibular septum) and rudimentary (complete lack of the inflow part) chambers allow the anatomic essence of the defect to be regarded from new viewpoint and to consider a possibility of performing new operations, anatomo-physiological in nature, in contrast to "hemodynamical" performed previously.