Relationship of left ventricular dyssynchrony indices by age Age group PSD HBW < 50 (n = 6) 54 ± 19.92 163.2± 60.32 50 - 59 (n = 26) 53.8 ± 18.97 170.1± 74.93 60 - 69 (n = 31) 51.8± 18.99 176.3± 75.35 ≥ 70 (n = 43) 42.6± 19.11 129.3 ± 62.92 p (test for trend) < 0.05 < 0.05 There are significant differences between the PSD and HBW indices among age groups.