Giant Saccular Aneurysm of the Right Coronary Artery.

Coronary artery aneurysm (CAA) is defined as a segmental coronary dilation that exceeds the diameter of the adjacent normal coronary artery 1.5 times. Its incidence in the general population is between 1.5% and 5%. However, CAAs over 10 mm are extremely rare. The cause of CAA in this patient with diffuse coronary artery disease was evaluated as atherosclerosis. CAA lesion was not the cause of acute coronary syndrome in our patient. Therefore, CAAS can remain asymptomatic for many years. Individuals with systemic diseases, such as Kawasaki's disease and Behçet's disease, should be followed up for CAAS.