P13.25: Vascular resistance analysis during L‐arginine therapy

Abstract

to assess the vascular resistance changes on the basis of abnormal Doppler velocimetry results in pregnancies complicated by intrauterine growth restriction (IUGR) or pregnancy induced hypertension (PIH) during L-arginine therapy. the study group included 61 pregnant women between 24–36 week of gestation treated L-arginine (L-A) or placebo (PL). IUGR was defined on the basis of estimated fetal weight less than 5 percentile for gestational age and PIH was diagnosed when blood pressure exceeded 140/90 after the 20th week with/without proteinuria and edema. Pulsatility index (PI) in the umbilical artery (UA), the middle cerebral artery (MCA) and uterine arteries (UTA) before the therapy, after 2 weeks, and at the time of delivery were measured. PI values were defined as abnormal when PI > 1.2 in the UTA, PI > 95th percentile in the UA, PI < 5th percentile in the MCA. The incidence of abnormal PI before, after 2 weeks, and before delivery was calculated and compared between L-A and PL group. We found 52.4% abnormal records in L-A group in the beginning, 51.2% after 2 weeks, and 50.2 at the time of delivery (63.2%; 83.3%; 81.2% in PL group, respectively). The percentage of abnormal PI results increased significantly in PL group when compared to A-L group as well after 2 weeks as at the time of delivery. While the percentage of abnormal PI results in the L-A remains relatively stable. However, when the blood flow in the UTA was analyzed separately, there were no statistical significant differences in the frequency of abnormal vascular resistance appearance (L-A: 38.1%; 41.5%; 48.0%; PL: 57.9%; 66.7%; 28.6%, respectively). L-arginine therapy may reduce incidence rate of abnormal vascular resistance in pregnancies complicated by PIH and IUGR. Surprisingly, this effect was on evident in the UTA. The hemodynamic effect was more pronounced in the UA and MCA. Supported by grant KBN 3PO5E 072 24