In a cohort of patients with severe aortic stenosis (AS) who underwent aortic valve replacement (AVR), the degree of myocardial fibrosis provides significant prognostic information in women and men, according to a study published Feb. 19 in JAMA Cardiology.

Soongu Kwak, MD, et al., prospectively evaluated 822 patients from 13 international sites with severe AS who underwent cardiovascular magnetic resonance (CMR) imaging before surgical or transcatheter AVR between March 2011 and September 2021. The authors investigated sex differences in myocardial fibrosis and left ventricular (LV) remodeling as well as the prognostic role of extracellular volume fraction (ECV%) and late gadolinium enhancement (LGE).

The main analysis included 670 patients without obstructive coronary artery disease (CAD), defined as those without a history of myocardial infarction or concomitant CABG; 45% were women. Age (about 72 years), comorbidities and AS were similar in women and men, but women were more symptomatic.

Results showed that ECV% was similar between sexes; however, women had lower LGE (both infarct and noninfarct) than men. Specifically, women had less wall thickening, hypertrophy and replacement myocardial fibrosis than men. After a median follow-up of 3.7 years, 76 (11.3%) deaths occurred (29 cardiovascular) in patients without obstructive CAD.

Increasing ECV% and LGE were associated with a higher incidence of the primary outcome of all-cause mortality and the secondary outcome of cardiovascular mortality in both sexes. Both noninfarct and infarct-related LGE were associated with increased mortality in the entire population (n=822), without significant interaction by sex.

The authors write that "increased myocardial fibrosis provided important prognostic value for both sexes" in this study, and that "noninvasive fibrosis assessment using CMR may improve risk stratification and decision-making," including optimal timing of AVR, regardless of sex.