Oral Isradipine and Feto-Maternal Hemodynamics in Hypertensive Pregnancy

Abstract

The effect of the calcium channel blocker, isradipine, on blood pressure and on uteroplacental and fetal blood flow was investigated in 27 patients with hypertension in pregnancy, before and after one week's treatment with 2.5 - 5.0 mg b.i.d. of the drug. In addition 21 hypertensive pregnant women without pharmacological treatment were investigated twice with a one week interval with regard to the same hemodynamic variables. Uteroplacental blood flow was investigated with dynamic placental scintigraphy. The uterine artery, the umbilical artery and fetal thoracic aortic blood flow velocity was measured by spectral doppler ultrasound. In the untreated group the blood pressure remained constant, and there were neither any changes in the uteroplacental or fetal blood flow vartiables. In the isradipine group there was a significant reduction in mean arterial blood pressure from 117 rnmHg to 112 mmHg (p<0.001). Treatment with isradipine did not affect the uteroplacental blood flow or the maternal and fetal blood flow velocities.