When should the root be replaced in TAAAD?
It is clear that replacement of the aortic root should be performed if the aortic root is aneurysmal or extensively destroyed in patients with TAAAD(10). It has been realized that the classic teaching of supracomissural repair (SCR) for all patients is inappropriate due to the documented increase in reoperation rates(11). However, the decrease in reoperation rate observed following root replacement is associated with an increase in cardiopulmonary bypass (CPB) time(11). Furthermore, it is well documented that the increase in CPB time is associated with a pronounced increase in mortality and morbidity(12, 13). Therefore, multiple investigators studied the risk factors for reoperation following limited repair in TAAAD to identify a cohort of patients that would benefit the most from extensive root repair(14). While the data is mostly retrospective and single institution, the risk factors identified for reoperations on the aortic root following SCR include: dilated aortic annulus > 27 mm, the use of glue, Age <60, Marfan syndrome, the number of sinuses involved, (11, 14-17). At Emory, our policy is to replace the aortic root if the aortic root diameter is >4.5 cm, the tear is located in the root, in young patients, and patients suspected to have connective tissue disease. We do not perform root replacement in patients with evidence of malperfusion or clinically unstable patients. We believe that a shorter CPB time is of paramount importance in TAAAD patients who have complex clinical presentation.