The cardiovascular system

The cardiovascular system consists of the heart, arteries, veins, and connecting vascular beds. The heart is an ovoid to valentine, asymmetric muscular dual pump structure. The right heart provides for the functional pulmonary circulation while the left side of the heart supplies the systemic circulation; the relative thickness of the ventricular walls reflects the differences in work load. The left ventricle forms the apex of the heart with the right ventricle spiraling across the ventral surface. Prominent coronary vessels embedded in epicardial fat in the coronary sulcus demarcate the approximate positions of the different cardiac chambers. Few veterinarians fondly recall learning the embryology of the heart; however, a basic understanding of this process is important to appreciating normal cardiac anatomy and provides the conceptual framework for understanding congenital heart disease. The epicardial surface of the heart normally has fat, particularly in the epicardial sulci surrounding the coronary vessels.