DOPPLER VELOCIMETRY OF MATERNAL RENAL INTERLOBAR ARTERIES IN PREGNANCY-INDUCED HYPERTENSION

OBJECTIVES: To evaluate whether Doppler velocimetry of maternal renal interlobar arteries is altered in patients with hypertensive disorders of pregnancy (PIH). METHODS: Flow velocity waveforms (FVWs) were obta ined, by means of color and pulsed Doppler ultrasound, from the renal artery and two interlobar arteries in the right kidney of 46 normal pr egnant women and 10 patients with PIH between 20 and 39 weeks' gestati on. Statistical analyses of resistance indices (RI) were performed by regression analysis, paired and unpaired t-tests. RESULTS: RI values o f renal and interlobar arteries in normal patients did not change sign ificantly with gestational age. Interlobar arteries had significantly lower RI values than corresponding main renal arteries (T = 3.88, P < 0.001). No significant differences in FVWs of renal (T = 1.86, P = 0.0 68) and interlobar arteries (T = 0.85, P = 0.399) were found between n ormal and hypertensive patients. A statistical power analysis confirme d that our sample size was sufficient to detect a difference in RI of 0.10, with alpha = 0.05 and beta = 0.80. CONCLUSIONS: FVWs of the vena l and interlobar arteries are not altered in patients with mild PIH.