Pulsatile Hemodynamics of Prehypertension and Hypertension: Associations with Pressure and Sex

Prior studies report abnormal pulsatile arterial hemodynamics in hypertensives. Small patient numbers preclude determining whether and how those abnormalities are associated with pressure or sex. In a large population of young hypertensives, we examine these associations.

During catheterization, we acquired high-fidelity pressure and flow signals to calculate hemodynamic parameters: flow (Q), input resistance (R), total (W_t) and oscillatory power (W_o), W_o/W_t, first harmonic of impedance modulus (Z₁), characteristic impedance (Z_c), first zero-crossing of impedance phase (F₀), compliance (C₀), backward (P_b), and forward (P_f) pressure wave amplitude and wave reflection index (P_b/P_f). We deem parameter correlation with systolic pressure as an association. Parameter differences between groups stratified into prehypertensive (PH), stage1 (S1), and stage2 (S2) pressure levels constitute a different type of association. With the population separated by sex, we repeat the analyses to ascertain sex and body size differences in these associations.

The PH, S1, and S2 groups have 16, 30, and 51 patients. All parameters except F₀ correlate with systolic pressure. R, Z₁, P_f, P_b, P_b/P_f, and C₀ differ between S2 and both S1 and PH, but only P_b differs between PH and S1. When separated by sex, and normalized by body size, those parameters, plus W_o/W_t, differ between men vs. women.

The similarity in hemodynamic parameters between PH and S1 suggests vascular abnormalities may predate the onset of hypertension. That, plus the various pressure associations and sex differences of the parameters, have implications for treatment, especially for women and prehypertensives.