FETAL AND MATERNAL DOPPLER MODIFICATIONS DURING THERAPY WITH ANTIHYPERTENSIVE DRUGS

Objective: The purpose of our study was to evaluate the eventual modifications of flow velocity waveforms in fetal-maternal circulation during therapy with nifedipine and atenolol. Methods: We studied 22 pregnant women with hypertension-preeclampsia between 20 and 36 weeks' gestation. Twelve patients were treated with 50 mg/day of atenolol and 10 received 40-80 mg/day of nifedipine. We evaluated pulsatility and resistance index in umbilical, aortic, cerebral, and uterine arteries before therapy, at 60-120 min, and 2 days after nifedipine intake. In the atenolol group, the Doppler study was performed before dosing, at 5 and 24 h, and at 7 days after starting therapy. Results: No significant differences were shown in umbilical and uterine circulation at any time in the patients treated with nifedipine; we noted a significant percentage increase in pulsatility index (PI) values in the middle cerebral artery at 60 min (P < 0.03). However, at 120 min and 48 h, the values returned to similar basal levels. In the group of patients treated with atenolol, no significant percentage changes were noted in the umbilical district; in the middle cerebral artery we found a slow jet progressive decrease in PI values with a significant difference at 7 days (P < 0.01). The aortic PI changes showed an opposite pattern with a significant percentage increase at 7 days (P < 0.03). In the uterine district we also noted a progressive increase in the resistance index (RI) values (at 7 days P < 0.05). Conclusions: In our experience, the use of nifedipine could be safer than atenolol in hypertensive pregnancies, with less harmful effects on fetal-maternal circulation.