Hemodynamic and antihypertensive effects of felodipine in patients with essential hypertension: A pilot study

The cerebrovascular and renal actions of antihypertensive agents are important clinically. The aim of the present study was to assess the effects of felodipine on cerebral blood flow (CBF) and renal blood flow (RBF) by a simple, noninvasive method for quantitative radionuclide angiography with 99m technetium (Tc)- dl -hexamethyl propylenamine oxime and 99m Tc-diethylenetriamine pentaacetic acid in patients with essential hypertension. Five patients with untreated mild-to-moderate essential hypertension were given felodipine twice daily (10 mg/d) for 4 weeks. The antihypertensive effect and the effects on CBF, RBF, and blood viscosity were tested before and on completion of the active treatment. The CBF and RBF were measured by radionuclide angiography coupled with single-photon emission computed tomography after intravenous administration of the radioactive agents. After administration of felodipine, systolic and diastolic blood pressures decreased significantly ( P P P