RELATIONSHIP BETWEEN PROGRESSION OF AORTIC VALVE CALCIFICATION AND HEMODYNAMIC SEVERITY OF AORTIC STENOSIS: RESULTS FROM THE PROGRESSA STUDY

Abstract

Recent studies reported that aortic valve calcification (AVC) as measured by multidetector computed tomography (MDCT) is a strong determinant of hemodynamic severity, as well as disease progression and provides incremental prognostic value for survival in patients with calcific aortic stenosis (AS). There is, however, a lack of data on the relationship between AVC progression and AS hemodynamic progression and the effect of sex on this relationship. The objective of this study was to assess the relationship between AVC and hemodynamic progression during long-term follow-up in patients with AS. Fifty-one consecutive patients (64±12 years, 75% male) with mild or moderate AS prospectively recruited in the PROGRESSA study were included in this subanalysis. We included in this analysis the patients who had underwent Doppler-echocardiography and MDCT exams at baseline, 2-year, and 4-year to measure hemodynamic and anatomic (i.e. AVC) progression of AS. AVC was measured using the Agatston method and expressed in arbitrary units (AU). In the study group, baseline AVC and mean gradient (MG) were (median [IQR]) 471[244-947]AU and 13[12-16]mmHg, respectively. AVC and MG increased significantly from baseline to 4 years follow-up (absolute increase in AVC: +274[90-748]AU or annualized increase +69[23-198]AU/year) (MG: +4.0[1.9-7.3]mmHg or +1.0[0.5-1.7]mmHg/year) (all p < 0.0001). AVC and MG progression rates were strongly correlated (r=0.71; p < 0.0001). When comparing women versus men, baseline AVC was, as expected, lower in women (258[75-440] vs. 577[309-991]AU; p=0.008) but baseline MG was similar between both sexes (13[11-16] vs. 14[12-16]mmHg, p=0.46). AVC progression was significantly faster in men than women (+358[114-892] vs. +147[75-198]AU, p=0.008), however there was no significant difference in MG progression (+4.7[1.9-7.9] vs. +2.3[1.8-4.7]mmHg, p=0.19). AVC and MG progression rates were closely correlated in men (r=0.81, p < 0.0001) but not in women (r=0.19, p=0.54). These findings were further corroborated by a significant interaction between sex and follow-up time with respect to AVC progression (p=0.03), but not to MG progression (p=0.17) (Figure). In this series of patients with mild to moderate AS at baseline, there was a strong relationship between aortic valve calcium load and hemodynamic progression rates during long-term follow-up. However, faster progression of aortic valve calcification is closely associated with greater hemodynamic progression of AS in men but not in women. In women, the hemodynamic progression of AS may be related to other pathologic processes including progression of valvular fibrosis. Further studies are needed to better understand the sex-related differences in calcific AS.