Figure 1.

Effects of I/R injury on left ventricular systolic and diastolic function as well as cardiac hypertrophy during aging. Overall design of the 8‐week study in young and old mice subjected to ischemia/reperfusion (I/R) injury or Sham operation (a). Left ventricular function was evaluated with echocardiography (Echo). Left ventricular (LV) ejection fraction (EF) as measured by VEVO Strain Software with modified Simpson method (single plane) (b) and LV internal diameter in diastole (LVIDd) (c) as measured by standard Echo at baseline as well as at 1, 4, and 8 weeks post‐surgery in Sham and I/R groups. Isovolumetric relaxation time (IVRT) (d), IVRT normalized to RR interval (IVRT/RR) (e), E/A ratio (f) (measured with standard Echo) and heart weight to body weight ratio (HW/BW) (g) were evaluated at 8 weeks post‐surgery in Sham and I/R groups. n = 8–14 per group. #p < 0.01 versus Sham_Old and I/R_Old; ##p < 0.05 versus Sham_Old, p < 0.001 versus I/R_Young, p < 0.0001 versus I/R_Old; ^p <0.01 versus Sham_Old, p < 0.0001 versus I/R_Young and I/R_Old; ^^p <0.05 versus I/R_Young and p < 0.01 versus I/R_Old; §p < 0.05 versus Sham_Old and I/R_Old; §§p < 0.05 versus I/R_Young, p < 0.01 versus I/R_Old; &p < 0.05 versus I/R_Young, p < 0.0001 versus I/R_Old; &&p < 0.05 versus Sham_Old and I/R_Young; @p < 0.01 versus I/R_Young, p < 0.0001 versus I/R_Old; @@p < 0.01 versus Sham_Old, p < 0.05 versus I/R_Young. *p < 0.05 between groups; **p < 0.01 between groups; ***p < 0.001 between groups; ****p < 0.0001 between groups. Linear mixed effect model with pair‐wise comparisons between groups at each time points using Tukey's multiple test correction method or one‐way ANOVA with Tukey's multiple test correction method were used between groups