ABSTRACT
The heart is a mediastinal structure that lies within the pericardial sack, such that one-third of its bulk is to the right of the midline. The cardiac long axis has oblique orientation in relation to the sagittal plane of the body, with the base in right superior location and the apex extending anterior inferior and to the left in a position called levocardia. Rarely, a normal heart is located in the right hemi-thorax and the cardiac apex anterior and to the right in a position called dextrocardia.
