The atria of the heart are separated from the ventricles by the<unk>  (coronary groove, auriculoventricular groove, atrioventricular groove); this contains the trunks of the nutrient vessels of the heart, and is deficient in front, where it is crossed by the root of the pulmonary artery.
Coronary sulcus
Anterior interventricular sulcus
Coronary sinus
Atrioventricular nodal branch
Atrioventricular canal
Interventricular septum
Aortic sinus
Posterior interventricular sulcus