Greater renal vascular involvement in the black patient with essential hypertension. A comparison of systemic and renal hemodynamics in black and white patients.

Systemic, splanchnic, and renal hemodynamic data were derived from 60 male and female, black and white, untreated and uncomplicated patients with essential hypertension. The systemic hemodynamic data confirmed our previous findings that at any level of arterial pressure, when black and white patients are matched for age, sex, and mean arterial pressure, cardiac index and total peripheral resistance were similar. This suggests that hypertensive vascular disease is no more severe in the black. This concept was supported further with respect to the splanchnic vasculature; however, renal blood flow was less and renal vascular resistance was higher at any level of mean arterial pressure (or total peripheral resistance) in the black. These physiological findings lend credence to those reports suggesting that at any level of pressure, hypertensive disease and morbidity (e.g., renal impairment) are more severe in the black patient. In addition, these data underscore the importance of understanding regional circulatory characteristics and they do not necessarily follow pari passu measured indices of systemic hemodynamics.