Central MessageCurrent guidelines use aortic diameter as the primary metric guiding management of patients with thoracic aneurysms. Aortic length and, its surrogate volume, may ultimately prove better predictors AAEs.This Invited Expert Opinion provides a perspective on following paper: J Am Coll Cardiol. 2019 Oct 15;74(15):1883-1894. https://doi.org/10.1016/j.jacc.2019.07.078.See Commentaries ...