The right atrial appendage is a common site for placement of atrial leads in pacemakers and defibrillators. Where is it located?

• A. Anteriorly and superiorly (superior to the fossa ovalis)
• B. Posteriorly near the aorta
• C. Within the left atrium
• D. On the posterior wall of the left ventricle

Answer: (A)

The right atrial appendage sits on the anterior wall of the right atrium and projects toward the front and top, making it anterior and superior to the fossa ovalis on the interatrial septum. This position, along with its rich pectinate musculature, provides a stable, easily accessible site for placing atrial pacing leads, which is why the appendage is the common choice for atrial leads in pacemakers and defibrillators.

The other described locations don’t match the true anatomy: they refer to regions not in the right atrial appendage (such as areas near the aorta or within the left atrium or left ventricle).