Elective surgery is indicated for aneurysms that are Large Rapidly enlarging (> 0.5 cm / year) Causing bronchial compression Causing aortobronchial or aortoesophageal fistulas Symptomatic Traumatic Mycotic Aneurysms of the ascending aorta are generally considered large if the diameter is > 5.5 cm or twice the native size of the ascending aorta or if the aortic size index (aortic diameter in relation to body surface area) is ≥ 2.75 cm / m 2.