Indexes of LV function measured by cardiac catheterization at week 8. Values are means ± SE; N = 16 for WT/HC, 17 for WT/CIH, and 15 for others. A: LV end-diastolic pressure (LVEDP). B: systemic vascular resistance (SVR). C: cardiac output (CO). D: the first derivatives of LV pressure rise (dP/dtmax). *P < 0.05; **P < 0.01. Significance of interaction between genotype (WT or KO) and exposure (HC or CIH): NS for SVR, LVEDP, CO, and dP/dtmax.