Perspective:

People with BAV are known to be at risk for AAo dilation and its associated complications. Potential explanations include a proposed theory of a primary bicuspid aortopathy, with the assumption of an abnormal aortic wall matrix that is susceptible to dilation; and a hemodynamic hypothesis, postulating that abnormal flow mediated by the BAV results in aortic wall alterations. Previous studies have variably associated valve morphology, valve function, and ascending aorta morphology with AAo dilation; and specific risk factors for progressive AAo dilation have not been definitively established. This retrospective study found an association between larger areas of elevated WSS in the AAo and in the entire aorta using four-dimensional flow CMR with higher rates of AAo dilation, adding support that hemodynamics plays a role in progressive AAo dilation. The study was relatively small, CMR techniques were not consistent throughout the follow-up interval, the retrospective study design could have introduced bias, and aortic dilation is taken as a surrogate for clinical complications. Ideally, prospective studies should be used to confirm the findings and to help inform clinical recommendations for the identification of patients with BAV who may be at increased risk of progressive AAo dilation and its clinical complications.