Aortic arch width by CMR is highly reproducible between readers and across imaging sequences

Background Aortic arch width (AAW) is defined as the distance between the centroids of the ascending and descending thoracic aorta at the level of the main pulmonary artery bifurcation, measured from an axial image. Previously, in a cohort of >3000 community-dwelling adults who underwent chest computed tomography for research purposes, we found that increased AAW is an independent predictor of incident adverse cardiovascular disease (CVD) events, even after adjustment for traditional CVD risk factors, and for coronary artery calcium. Thus AAW may be useful for risk stratification. In this study, we sought to assess the agreement in AAW measured using two CMR sequences: black-blood (BB) and phase contrast flow (QF) methods. We hypothesized that AAW would not differ between the two sequences, and that reader reproducibility would be high regardless of sequence.