Sex differences in aortic root and vascular anatomy in patients undergoing transcatheter aortic valve implantation: A computed-tomographic study

Background Very little data exist on the impact of sex on aortic and arterial anatomy as relevant for transcatheter aortic valve implantation (TAVI). Objective To investigate whether patients with severe aortic stenosis (AS) referred for TAVI display sex-specific differences in aortic root and ilio-femoral artery size. Methods In 506 patients referred for pre-procedural CT evaluation before TAVI we performed a detailed assessment of aortic root anatomy: size of the annulus and the sinus of Valsalva (SoV), diameter of the sino-tubular junction (STJ), and distance of the coronary artery ostia to the aortic annulus plane; we also determined the dimensions of aorta, subclavian, and ilio-femoral arteries. Results Women had significantly smaller aortic root dimensions (annulus mean diameter: 22.9 ± 2.2 mm vs. 25.7 ± 2.7 mm, SoV mean diameter: 31.8 ± 4.2 mm vs. 36.3 ± 3.8 mm, STJ mean diameter: 26.3 ± 3.4 mm vs. 29.8 ± 4.2 mm) and lower left and right coronary artery ostia take-off (12.3 ± 2.4 vs. 14.1 ± 2.9 mm; 14.8 ± 2.6 vs. 17.1 ± 3.2 mm, respectively) than men (P < 0.001 for all), even after adjustment for their smaller body surface area (BSA) and height. Dimensions of the ascending aorta, subclavian and ilio-femoral arteries were also significantly smaller in women, but not when adjusted for BSA. Conclusions Women with severe AS had smaller aortic root dimensions even after correcting for their smaller body size and height, reflecting a sex-specific difference. In contrast, sex-related differences in aortic, subclavian, and ilio-femoral dimensions were fully explained by the smaller BSA of women.