An 89 year-old female presented with a slightly tender mass on her sternum (Panel 1). She had been complaining of a mild, dull ache in her chest for a few months prior to her presentation. Her past medical history included two surgical median sternotomy surgeries. She underwent aortic valve replacement with a bioprosthetic valve at the age of 66, followed by redo aortic valve and aortic root replacement 17 years later. She looked well on physical examination with equal pulses and blood pressure measurements on both arms. A soft, pulsatile mass (3.8 x 3 x 2.8 cm) was noted on the sternum (Panel 1).