In which structure is the crista terminalis located?

The crista terminalis is a prominent ridge located in the right atrium of the heart. It serves as a key anatomical landmark that demarcates the border between the smooth-walled portion of the right atrium (the sinus venarum) and the rough-walled area where the pectinate muscles are found, originating from the right auricle. The presence of the crista terminalis is significant because it is where various structures, such as the superior vena cava and the opening of the inferior vena cava, converge. This ridge also plays a role in the conduction system of the heart by providing an attachment point for the pectinate muscles and helping with the organization of electrical impulses through the atrium.

The left atrium, right ventricle, and left ventricle do not contain the crista terminalis, as this structure is specific to the right atrial anatomy. Understanding the correct location and function of the crista terminalis is important for interpreting echocardiographic findings and recognizing normal versus abnormal cardiac anatomy.