Introduction: Aortic Stenosis (AS) is a common valve disease of the adult, caused by calcification of aortic cusps. The relationship between cusp calcification and severity of AS has been established mostly in men and it is unclear whether the calcification process and its relation to AS severity is similar in women Hypothesis: We hypothesized that the physiologic relation between aortic valve calcification (AVC) load and AS severity is different in men and women and that lower calcification loads may lead to severe AS in women Methods: We prospectively performed high resolution computed tomography (CT) without contrast in 679 patients with AS (Aortic valve area (AVA) <2cm 2 , Mean gradient ≥10 mmHg) at two academic centers (Rochester, MN; Paris, France) to measure AVC scores and compare these to the hemodynamic obstruction measured by Echo-Doppler. Results: Women vs. men were older (76±11 vs 74±11, p<0.0001) with slightly higher ejection fraction (62±12 vs 59±13, p=0.001) but AS severity was similar (AVA/body surface area 0.55±0.2 vs 0.56±0.2 cm 2 /m 2 ; Peak velocity 4±1 vs 3.9±1 m/s; Mean gradient 41±21 vs 38±18 mmHg, all p≥0.1). Yet, AVC load was lower in women vs men, score absolute or normalized for LVOT area (551±383 vs 626±399 all p<0.0001). For those with severe AS (Mean gradient >40 mmHg), AVC scores were 2433±1412 in women vs 3805±1587 in men. Multivariate analysis adjusting for age, BSA, LVOT area and mean gradient, confirmed that severe AS was achieved with lower AVC load in women (all p<0.0001). Conclusions: In this large multicenter AS population, women reached similar AS severity than males for lower calcium loads, even after adjustment for lower body and LVOT size. Hence the relation between valvular calcification process and severity of AS differs in women vs. men. Thus, future studies are needed to determine the differential mechanism of aortic calcification in men and women and diagnostic consideration must be given to gender in the interpretation of AS severity by AVC load.
Sex Differences in Aortic Valve Calcification Measured by Multidetector Computed Tomography in Aortic Stenosis
Background— Aortic valve calcification (AVC) is the intrinsic mechanism of valvular obstruction leading to aortic stenosis (AS) and is measurable by multidetector computed tomography. The link between sex and AS is controversial and that with AVC is unknown. Methods and Results— We prospectively performed multidetector computed tomography in 665 patients with AS (aortic valve area, 1.05±0.35 cm 2 ; mean gradient, 39±19 mm Hg) to measure AVC and to assess the impact of sex on the AVC–AS severity link in men and women. AS severity was comparable between women and men (peak aortic jet velocity: 4.05±0.99 versus 3.93±0.91 m/s, P =0.11; aortic valve area index: 0.55±0.20 versus 0.56±0.18 cm 2 /m 2 ; P =0.46). Conversely, AVC load was lower in women versus men (1703±1321 versus 2694±1628 arbitrary units; P <0.0001) even after adjustment for their smaller body surface area or aortic annular area (both P <0.0001). Thus, odds of high-AVC load were much greater in men than in women (odds ratio, 5.07; P <0.0001). Although AVC showed good associations with hemodynamic AS severity in men and women (all r >0.67; P <0.0001), for any level of AS severity measured by peak aortic jet velocity or aortic valve area index, AVC load, absolute or indexed, was higher in men versus women (all P ≤0.01). Conclusions— In this large AS population, women incurred similar AS severity than men for lower AVC loads, even after indexing for their smaller body size. Hence, the relationship between valvular calcification process and AS severity differs in women and men, warranting further pathophysiological inquiry. For AS severity diagnostic purposes, interpretation of AVC load should be different in men and in women.