Hemodynamic characterization of hypertensive patients with an exaggerated orthostatic blood pressure variation

Exaggerated orthostatic blood pressure variation (EOV) is a poorly understood phenomenon related to high cardiovascular risk. We aimed to determine whether hypertensive patients with EOV have a distinct hemodynamic pattern, assessed through impedance cardiography.

In treated hypertensive patients, we measured the cardiac index (CI), systemic vascular resistance index (SVRI), blood pressure (BP), and heart rate (HR) in the supine and standing (after 3 minutes) positions, defining three groups according to BP variation: 1) Normal orthostatic BP variation (NOV): standing systolic BP (stSBP)-supine systolic BP (suSBP) between -20 and 20 mmHg and standing diastolic BP (stDBP)-supine diastolic BP (suDBP) between -10 and 10 mmHg; 2) orthostatic hypotension (OHypo): stSBP-suSBP≤-20 or stDBP-suDBP≤-10 mmHg; 3) orthostatic hypertension (OHyper): stSBP-suSBP≥20 or stDBP-suDBP≥10 mmHg. We performed multivariable analyses to determine the association of hemodynamic variables with EOV.

We included 186 patients. Those with OHyper had lower suDBP and higher orthostatic SVRI variation compared to NOV. In multivariable analyses, orthostatic HR variation (OR = 1.06 (95%CI 1.01-1.13), p = 0.03) and orthostatic SVRI variation (OR = 1.16 (95%CI 1.06-1.28), p = 0.002) were independently related to OHyper. No variables were independently associated with OHypo.

Patients with OHyper have a distinct hemodynamic pattern, with an exaggerated increase in SVRI and HR when standing.