Background
Chronic increasing in arterial afterload may be an important trigger for left ventricular (LV) remodeling and dysfunction that lead to heart failure (HF). Racial differences in the predisposition to HF are well described, but the underlying mechanisms remain unclear.
Objective
We evaluated the racial differences in arterial elastance (Ea), which reflects the arterial afterload faced by the LV, and its associations with cardiac structure and function. We hypothesize that the LV in blacks displays heightened afterload sensitivity as compared to whites.
Methods
We studied 5727 community-based, elderly Atherosclerosis Risk in Community (ARIC) Study participants (22% black), who underwent echocardiography between 2011 and 2013.
Results
Blacks were younger (75 ± 5 vs 76 ± 5 years old), more frequently women (66 vs 57%), and had higher prevalence of obesity (46 vs 31%), hypertension (94 vs 80%), and diabetes mellitus (47 vs 34%) than whites. Adjusting for these baseline differences, Ea was higher among blacks (1.96 ± 0.01 vs 1.80 ± 0.01 mmHg/mL). In blacks, Ea was associated with greater LV remodeling (LV mass index, β = 3.21 ± 0.55 g/m2, p<0.001) and higher LV filling pressures (E/e′ ratio, β = 0.42 ± 0.11, p<0.001). These relationships were not observed in whites (LV mass, β = 0.16 ± 0.32 g/m2, p=0.61, p for interaction <0.001; E/e′ratio, β = −0.32 ± 0.06, p<0.001, p for interaction <0.001)..
Conclusion
These community-based data suggest that black Americans display heightened afterload sensitivity as a stimulus for LV structural and functional remodeling, which may contribute to their greater risk of HF, as compared to white Americans.