The Anatomy and Physiology of the Heart

The heart is a rhythmic and dynamic muscular organ that plays a pivotal role in sustaining life by ensuring continuous blood circulation throughout the body. This chapter presents a comprehensive overview of the heart’s anatomical structures and physiological functions in mammals. It begins with the organization of cardiac tissues, including cardiomyocytes and the conduction system, which enables synchronized contraction and efficient hemodynamics. Special emphasis is placed on the electrophysiological properties of cardiac cells, the generation of action potentials, and the roles of ion channels, the cardiac electrical conduction system, generation of electrocardiography and its interpretation, as well as the mechanisms of arrhythmia. The chapter also explores the cardiac cycle, detailing pressure-volume relationships and regulation of cardiac performances. Furthermore, it discusses valve mechanics, the origination of heart sounds, illustrations of phonocardiograms of normal and common abnormal heart sounds. This chapter serves as a fundamental resource for students and professionals in veterinary and biomedical sciences seeking a solid foundation in cardiovascular anatomy and physiology.