Aortic Valve Calcification Density Measured by MDCT in the Assessment of Aortic Stenosis Severity.

BACKGROUND: Aortic valve calcification (AVC) indexation to the aortic annulus (AA) area measured by Doppler echocardiography (AVCdEcho) provides powerful prognostic information in patients with aortic stenosis (AS). However, the indexation by AA measured by multidetector computed tomography (AVCdCT) has never been evaluated. The aim of this study was to compare AVC, AVCdCT, and AVCdEcho with regard to hemodynamic correlations and clinical outcomes in patients with AS. METHODS: Data from 889 patients, mainly White, with calcific AS who underwent Doppler echocardiography and multidetector computed tomography within the same episode of care were retrospectively analyzed. AA was measured both by Doppler echocardiography and multidetector computed tomography. AVCdCT severity thresholds were established using receiver operating characteristic curve analyses in men and women separately. The primary end point was the occurrence of all-cause mortality. RESULTS: Correlations between gradient/velocity and AVCd were stronger (both P≤0.005) using AVCdCT (r=0.68, P<0.001 and r=0.66, P<0.001) than AVC (r=0.61, P<0.001 and r=0.60, P<0.001) or AVCdEcho (r=0.61, P<0.001 and r=0.59, P<0.001). AVCdCT thresholds for the identification of severe AS were 334 Agatston units (AU)/cm2 for women and 467 AU/cm2 for men. On a median follow-up of 6.62 (6.19-9.69) years, AVCdCT ratio was superior to AVC ratio and AVCdEcho ratio to predict all-cause mortality in multivariate analyses (hazard ratio [HR], 1.59 [95% CI, 1.26-2.00]; P<0.001 versus HR, 1.53 [95% CI, 1.11-1.65]; P=0.003 versus HR, 1.27 [95% CI, 1.11-1.46]; P<0.001; all likelihood test P≤0.004). AVCdCT ratio was superior to AVC ratio and AVCdEcho ratio to predict survival under medical treatment in multivariate analyses (HR, 1.80 [95% CI, 1.27-1.58]; P<0.001 compared with HR, 1.55 [95% CI, 1.13-2.10]; P=0.007; HR, 1.28 [95% CI, 1.03-1.57]; P=0.01; all likelihood test P<0.03). AVCdCT ratio predicts mortality in all subgroups of patients with AS. CONCLUSIONS: AVCdCT appears to be equivalent or superior to AVC and AVCdEcho to assess AS severity and predict all-cause mortality. Thus, it should be used to evaluate AS severity in patients with nonconclusive echocardiographic evaluations with or without low-flow status. AVCdCT thresholds of 300 AU/cm2 for women and 500 AU/cm2 for men seem to be appropriate to identify severe AS. Further studies are needed to validate these thresholds, especially in diverse populations.

Angiotensin II receptor blockers are associated with reduced valvular fibrosis in females with aortic stenosis.

BACKGROUND: Angiotensin receptor blockers (ARBs) may slow down the progression of aortic stenosis (AS), through their antifibrotic effect. Females present more valvular fibrosis than males, thus ARBs may have more effect in females. Our aim was to assess the impact of ARBs on the remodeling of the aortic valve in males and females. METHODS: We included patients who had an aortic valve replacement± coronary bypass grafting between 2006-2013. Patients with missing echocardiographic or histologic data were excluded. Warren-Yong and fibrosis scores of the explanted valves were performed. Patients were divided into four phenotypes according to their Warren-Yong and fibrosis scores: Mild calcification/fibrosis group, Severe calcification/fibrosis group, Predominant fibrosis group, Predominant calcification group. RESULTS: Among the 1,321 included patients, the vast majority (89%) has severe AS. Patients in the predominant fibrosis group, as compared to the predominant calcium group, were more often females (39 vs 31%, p=0.008), bicuspid valves (44 vs 34%, p=0.002) and they less often used ARBs (25 vs 30%, p=0.046). Female sex was independently associated with being in the predominant fibrosis group (OR 1.45 [95% CI 1.08-1.95], p=0.01), with a significant interaction between female sex and ARBs. Females taking ARBs compared to females not taking ARBs had significantly lower fibrosis score (p<0.001). This difference was not seen in males. CONCLUSION: In this large series of patients with moderate-severe AS, among females there was a negative association between intake of ARBs and valvular fibrosis. Thus, the possible effects of ARBs may be sex-specific, with a larger therapeutic role in females.