CMR Study Reveals Sex-Specific Patterns in Aortic Stenosis: Women Show Better Survival Despite Similar Fibrosis Levels
核心洞察
A large international study of 822 aortic stenosis (搜索) patients found women had more favorable left ventricular remodeling patterns and lower late gadolinium enhancement (搜索) compared to men.
Despite similar extracellular volume fraction levels between sexes, women demonstrated superior overall survival rates (9.4% mortality) versus men (14.8% mortality) in cardiovascular outcomes.
Cardiovascular magnetic resonance imaging proved valuable for sex-based risk assessment, with myocardial fibrosis (搜索) measurements serving as significant mortality predictors for both male and female patients.
An international multicenter study has revealed important sex-specific differences in cardiac remodeling and outcomes among patients with aortic stenosis (搜索) (AS), highlighting the potential of cardiovascular magnetic resonance (CMR) imaging for personalized risk assessment.
The comprehensive study, published in JAMA Cardiology (搜索), analyzed 822 patients across six countries, including the United States, Canada, UK, Belgium, Germany, and South Korea. The cohort comprised 342 women (41.6%) and 480 men (58.4%), all of whom underwent CMR evaluation before aortic valve replacement.
Sex Differences in Cardiac Structure and Function
While both sexes showed comparable severity of AS and similar rates of comorbidities such as hypertension, diabetes, and atrial fibrillation, significant differences emerged in cardiac structural parameters. Women exhibited lower left ventricular (LV) mass index, wall thickness, and mass-to-volume ratios compared to men. Additionally, female patients demonstrated smaller LV volumes but maintained higher ejection fractions, though stroke volume indices remained similar between sexes.
Myocardial Fibrosis Patterns
A key finding was that while extracellular volume fraction (ECV%) measurements were similar between men and women, female patients showed lower levels of late gadolinium enhancement (搜索) (LGE). This suggests different patterns of myocardial fibrosis (搜索) development between sexes, potentially contributing to varying clinical outcomes.
Survival Outcomes and Risk Prediction
The study revealed superior survival rates among women, with cardiovascular mortality at 9.4% (32 deaths) compared to 14.8% (71 deaths) in men. Importantly, myocardial fibrosis (搜索) measurements proved prognostically significant for both sexes:
- Women: ECV% increase showed adjusted HR of 1.08 (95% CI, 1.04-1.12; P < .001)
- Men: LGE presence showed adjusted HR of 1.82 (95% CI, 1.0-3.32; P = .04)
Clinical Implications
These findings underscore the value of CMR imaging in risk stratification for AS patients, particularly in identifying sex-specific patterns of cardiac remodeling. The research suggests that women may develop more favorable remodeling patterns despite similar degrees of diffuse fibrosis, potentially explaining their better survival rates.
The study's lead investigators emphasized that these results represent a significant advance in understanding how ventricular decompensation differs between men and women with AS. This knowledge could help inform more personalized approaches to timing and management of aortic valve replacement procedures.