[Anatomy of atrioventricular discordances]

Nineteen anatomic specimens were revised, 10 in situs solitus and 9 in situs inversus. The type of atrioventricular connection, atrioventricular relation, the characteristics of atrioventricular valves and ventricular cavities, the atrial and ventricular septa, the conducting tissue, the type of arterio-ventricular connections, the anatomy of the coronary arteries and associated defects were studied. The anatomic features of the ventricular cavities differ from those in the normal heart with respect to the orientation of the atrio-ventricular valve rings, the implantation of the papillary muscles in both ventricles and the extention of the membranous septum. The most frequently found type of arterioventricular connection was discordant, followed by double-outlet right ventricle, concordant connections and finally single outlet. We did not find any case of double-outlet left ventricle. It is important to know the anatomy of the conducting tissue that is in close contact with the ventricular septal defects, the most common associated anomaly in our series, and with infundibular pulmonary stenosis.