Aerobic Training Attenuates Differences Between Black and White Adults in Left Ventricular-Vascular Coupling and Wasted Pressure Effort

Background: Black compared with White adults have a higher risk for left-ventricular hypertrophy and heart failure possibly due to the early onset of alterations in ventricular-vascular coupling (ie, arterial [E_a] to ventricular elastance [E_es] ratio) and wasted pressure effort (E_w). Aerobic training preserves the coupling ratio (E_a/E_es) and attenuates E_w, but whether this applies to Black adults is unknown. We hypothesized that Black rather than White adults would have greater training-induced improvements in the E_a/E_es and E_w.

Methods and results: Fifty-four young adults with normal blood pressure (Black=24 [58% female]; White=30 [47% female], mean=24 years; SD=5 years) completed an 8-week aerobic training (3 times/week, 65%-85% peak oxygen uptake). E_a/E_es was estimated via echocardiography and scaled to body surface area, and the E_w was estimated from pulse contour analysis. Black adults had lower E_a/E_es (difference (d)=0.49 [95% CI, 0.14-0.84 mm Hg/mL], P=0.007) and higher E_w (d=1127 [95% CI, 104-2007 dyne cm^-2 s], P=0.005). Both groups exhibited similar (race-by-training interaction, P=0.986) training-induced reductions in scaled E_a (d=-0.11 [95% CI, -0.18 to -0.04 mm Hg/mL], P<0.001). Only in White adults, scaled E_es increased (d_white=0.39 [95% CI, 0.11-0.32 mm Hg/mL], P=0.003) and E_a/E_es was reduced (d_white=-0.16 [95% CI, -0.33 to -0.18 mm Hg/mL/m²], P<0.001). Conversely, only Black adults exhibited reductions in E_w after training (d_black=-699 [95% CI, -1209 to -189 dyne cm^-2 s], P=0.008).

Conclusions: Aerobic training-induced differential effects on E_a/E_es and E_w of White and Black young adults hold the potential to reduce racial disparities. This warrants confirmation in a larger sample.

Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01024634.