Normal Cardiac Anatomy

Abstract

Diagnosis of congenital heart disease (CHD) requires a thorough appreciation of the normal cardiac anatomy. In fact, the recognition of “abnormal” anatomy hinges on the definition of “normal” anatomy. Ordinarily, most of the major systems develop in a midline position with bilateral mirror-image symmetry. However, the cardiovascular, respiratory, and digestive systems later become asymmetric and are characterized by their situs or position in the body. It is, therefore, not uncommon to observe the associated anomalies of the abdominal viscera in cardiac malposition.

In this chapter, we will review the definitions and abbreviations commonly used in the literature on CHD and discuss abdominal and atrial situs solitus, normal anatomy of the cardiac chambers, and common landmarks for the determination of the atria and ventricles.

The right atrium possesses a unique morphology and has several important landmarks, including the crista terminalis, Eustachian valve, Thebesian valve, and Chiari network. The connections between the atrioventricular valves are labeled according to their respective ventricle morphology. The morphologic determination of a ventricle and the definition of a ventricle are based on the so-called 50 % rule. The semilunar valves connect the ventricle to an associated great artery and are determined by their associated great arteries as the pulmonary valve for the pulmonary artery and the aortic valve for the aorta.