The surface of the heart has three major grooves or depressions. Such a groove is a sulcus. The coronary sulcus (atrioventricular groove) lies between the atria and ventricles. It is the site of the coronary arteries and coronary sinus (vein). Between the ventricles is the anterior interventricular sulcus, through which the anterior interventricular artery and great cardiac vein pass and the posterior interventricular sulcus, where the posterior interventricular artery and middle cardiac vein are found.
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