What is the name of the wall that separates the two superior chambers of the heart?

The wall that separates the two superior chambers of the heart is called the interatrial septum. This structure is crucial as it divides the left atrium from the right atrium, preventing the mixing of oxygenated blood from the left side of the heart and deoxygenated blood from the right side. Maintaining this separation is essential for efficient heart function and proper blood circulation throughout the body.

In this context, the interventricular septum, while also a significant structure, specifically separates the lower chambers (the ventricles) of the heart, which is not relevant to the question about the superior chambers. Similarly, terms like atrial wall and ventricular wall are not anatomically specific measures of separation between the chambers but rather general descriptions that do not accurately identify the interatrial septum's role.