Sex differences in left ventricular remodeling, myocardial fibrosis and mortality after aortic valve replacement

Objectives: To investigate sex-differences in left ventricular remodeling and outcome in patients undergoing surgical or transcatheter aortic valve replacement (SAVR/TAVR).
Methods: In this multicentre, observational, outcome study with imaging core lab analysis, patients with severe aortic stenosis (AS) listed for intervention at one of six UK centres were prospectively recruited and underwent cardiovascular magnetic resonance imaging (CMR). The primary endpoint was all-cause mortality and secondary endpoint was cardiovascular mortality.
Results: 674 patients (425 male, 249 female, age 7514 years) were included: 399 SAVR, 275 TAVR. Females were older, had higher surgical risk scores and underwent TAVR more frequently (53% vs. 33.6%, p<0.001). More men had bicuspid aortic valves (BAV) (26.7% vs. 14.9%, p<0.001) and demonstrated more advanced remodelling than females. During a median follow-up of 3.6 years, 145 (21.5%) patients died, with no significant difference in all-cause mortality (23.3% vs. 20.5%, p=0.114), but higher cardiovascular mortality in females (13.7% vs. 8.5%, p=0.012). There were no significant sex related differences in outcome in the SAVR or TAVR sub-groups, or after excluding those with BAV. Factors independently associated with all-cause mortality were age, left ventricular ejection fraction (LVEF), BAV (better) and myocardial fibrosis detected with late-gadolinium enhancement (LGE) in men; and age, LVEF and LGE in women. Age and LGE were independently associated with cardiovascular mortality in both sexes.
Conclusions: Men demonstrate more advanced remodeling in response to a similar severity of AS. The higher cardiovascular mortality observed in women following AVR is accounted for by females having less BAV and higher risk scores resulting in more TAVR. LGE is associated with a worse prognosis in both sexes.