Table 3.

Echocardiographic evaluation of cardiac functional parameters in aging female F344xBN rats (mean ± SEM)

Groups	6 months	26 months	30 months
E–E′	20.8 ± 1.02	14.7 ± 0.64	21.9 ± 2.63
E′	3.89 ± 0.14	3.42 ± 0.42	2.71 ± 0.19*
LV IVRT (s)	0.015 ± 0.002	0.036 ± 0.005*	0.030 ± 0.000
MV Dec Time (s)	0.053 ± 0.005	0.057 ± 0.002	0.063 ± 0.003
MV Emax (cm/s)	78 ± 3.3	62 ± 1.5*	55 ± 1.4*
MV Amax (cm/s)	42 ± 1.3	36 ± 0.9	35 ± 1.6*
MV E/A	1.75 ± 0.03	1.60 ± 0.06	1.66 ± 0.10
Ejection fraction (%)	74 ± 0.9	82 ± 1.0*	78 ± 1.8
Fractional shortening (%)	38 ± 0.7	46 ± 1.0	42 ± 1.7
ESV (ml)	0.143 ± 0.017	0.082 ± 0.005*	0.114 ± 0.10
EDV (ml)	0.535 ± 0.052	0.492 ± 0.20	0.523 ± 0.022
Heart rate (bpm)	281 ± 16.5	259 ± 8.8	278 ± 10.1

Six-month-old animals; 26-month-old animals; 30-month-old animals

*p < 0.05, significantly different from 6-month-old animals