What is the name of the wall that separates the left and right sides of the heart?

The wall that separates the left and right sides of the heart is known as the septum. This muscular structure plays a crucial role in maintaining the efficiency of the heart's function by preventing the mixing of oxygenated and deoxygenated blood. The septum is divided into two main parts: the interatrial septum, which separates the left and right atria, and the interventricular septum, which separates the left and right ventricles. This separation is vital for the heart to function properly, as it ensures that oxygen-rich blood from the left side does not intermingle with oxygen-poor blood from the right side, thereby facilitating optimal delivery of oxygen to the body tissues.

While the pericardium is the protective sac surrounding the heart, and the mediastinum is the area between the lungs that contains the heart, neither of these structures serves the function of separating the heart's chambers. Carina refers to the ridge at the division of the trachea into the bronchi and is unrelated to cardiac anatomy. Thus, identifying the septum as the wall that divides the left and right sides of the heart highlights its crucial anatomical and functional role in cardiovascular physiology.