<prompt> Torus aoicus is seen due to:Atrium bulging into the aoaAoic sinus bulging into left atriumAoic sinus bulging into right atriumAoic wall tear  <response>: Torus aoicus aoic mound is the prominent region of the right atrial septum, which marks the projection of the noncoronary aoic sinus into the right atrial wall. The bulge is superior to the coronary sinus and anterior to the fossa ovalis. The right coronary aery arises from the anterior right coronary aoic sinus; The left coronary aery arises from the left posterior left coronary aoic sinus. 