Left ventricular remodeling and fibrosis: Sex differences and relationship with diastolic function in hypertrophic cardiomyopathy.

Objectives: We investigated sex differences in left ventricular (LV) remodeling and fibrosis and their relationship with LV diastolic dysfunction by cardiovascular magnetic resonance (CMR).

Methods: CMR imaging was performed simultaneously in 152 age-matched patients (76 men, 76 women; mean age: 49±9 years) without LV systolic dysfunction. LV remodeling index (LVRI) was calculated as the ratio of LV mass and end-diastolic volume. Diastolic function indexes including peak filling rate (PFR) and time to PFR (tPFR) were evaluated. Extent of late gadolinium enhancement (LGE) was measured.

Results: LVRI and extent of LGE were greater in women compared with men (1.48±0.22 vs. 1.36±0.28g/ml; 13.15±2.48 vs. 11.35±2.34g, respectively, both P<0.001). Women had lower PFR and higher tPFR (both P<0.001) than men. LVRI and the extent of LGE showed significant relationships with parameters of diastolic function in both sex. In a multivariate analysis, LVRI remained a strong independent predictor of PFR and TPFR in women (β=-0.272, P=0.032; β=0.348, P=0.016, respectively), and in men (β=-0.374, P<0.001; β=0.660, P<0.001, respectively). Furthermore, the extent of LGE also remained an independent predictor of PFR in women (β=-0.283, P=0.033) and men (β=-0.492, P<0.001).

Conclusions: There are prominent sex differences in LV remodeling and myocardial fibrosis. We suggest that the effects of LV remodeling and fibrosis may lead to diastolic dysfunction with greater susceptibility to worse clinical outcome in women.