Fig. 1.

Left ventricular structural and functional changes are worsened by estrogen receptor (ER) antagonism. Temporal echocardiogram data demonstrating that ER antagonism with ICI-182,780 (ICI) exacerbated volume overload (VO)-induced remodeling. A: ICI treatment led to increased left ventricular (LV) end-diastolic diameter (LVEDD), indicating dilatation. Data are presented as increase above presurgery baseline measures for each animal. Baseline LVEDD for all groups combined was 6.18 ± 0.41 mm with no significant difference between groups. B: this increase in chamber size was associated with a significant decrease in ejection fraction (EF%) in the ICI-treated aortocaval fistula (ACF) group. Baseline EF% for all groups combined was 68 ± 2% with no significant difference between groups (n = 6–8 per group; *P < 0.05 vs. Sham; †vs. ACF).