Loeys-Dietz syndrome is a condition that predisposes the development of central and peripheral arterial aneurysms and dissections. The standard approach for treatment of these lesions has been open repair. We present the case of a 34-year-old woman with a previous history of multiple open aortic repairs who presented with a right large internal mammary artery aneurysm. The patient was successfully treated with endovascular coil embolization. This case report demonstrates the feasibility of using endovascular interventions to treat unusual aneurysms in patients with Loeys-Dietz syndrome.