Mitral valve E wave peak velocity (MV E) (a) and mitral valve A wave peak velocity (MV A) (b) significantly depend on age, but not sex or genotype. E/A ratio (c) significantly depends on age and genotype, but not sex, and is 10–14% lower in Eln+/− mice at 14 and 21d. IVRT (d) significantly depends on age, but not sex or genotype. Representative Doppler image with MV E and MV A peak velocity traces, and IVRT measurements for a mitral valve in a 3d WT mouse (e). n = 5–24/group.