The apex of the aortic arch backshifts with aging.

Abstract

Only a few studies, involving small numbers of patients, have globally assessed the curvature of the thoracic aorta but without any details concerning the location of the supra-aortic trunks. Using CT to describe normal aortic-arch morphology and its changes with age and sex. 344 CT scans were studied. We measured the distances from the apex to the ascending and descending aorta, the curvilinear length of the entire arch, that of the segment, including bifurcations of supra-aortic vessels, and the angle, height, and shift of the arch. In men, the arch was significantly longer (146.2 vs 122.8mm; p<0.001), higher (49.3 vs 40.1mm, p<0.001), and wider transversely (83.6 vs 73.3mm; p<0.001) than in women. The average men's arch also had a more acute angle at the apex (79.7° vs 83.7° p<0.001). Neither morphology nor age influenced the winding angle around the mediastinum. Aging was accompanied by deflection and extension of the aortic arch, which grew more anteroposteriorly (6.1mm/10years in men) than vertically (2.5mm/10years in men), while the apex moved towards the rear of the arch. The ascending aorta was the only curvilinear length unaffected by age, whereas the supra-aortic trunks parted from each other. We believe that all these original observations could lead to a better assessment of normal aging of the aorta and guide technical choices during surgical or hybrid procedures.