Renal Interlobar Vein Impedance Index as a First-Trimester Marker Does Not Predict Hypertensive Disorders of Pregnancy.
The purpose of this study was to examine whether the maternal renal interlobar vein impedance index as assessed by first-trimester sonography is able to predict the later development of hypertensive disorders of pregnancy.



Venous Doppler parameters of both maternal kidneys were studied in 214 pregnant women at gestational ages of 11 weeks to 13 weeks 6 days. Patients were classified according to outcomes related to hypertensive disorders. Detection rates and areas under receiver operating characteristic curves were determined for the maternal renal interlobar vein impedance index as a first-trimester predictor of preeclampsia and gestational hypertension.



Among the 214 patients, 22 (10.3%) developed preeclampsia; 10 (4.7%) developed gestational hypertension; and 182 were unaffected by hypertensive disorders (controls; 85.0%). In the overall study population, there was no difference in the impedance index between the right (0.44; 95% confidence interval, 0.35-0.50) and left (0.43; 95% confidence interval, 0.35-0.53) sides (P = .86). The average impedance index did not differ among women destined to develop preeclampsia (0.46; 95% confidence interval, 0.38-0.57), gestational hypertension (0.39; 95% confidence interval, 0.33-0.46), or pregnancies uncomplicated by hypertensive disease (0.42; 95% confidence interval, 0.37-0.50; P = .15). Low detection rates and the area under the curve analysis demonstrated that the impedance index was not predictive of hypertensive disorders of pregnancy.



The maternal renal interlobar vein impedance index should not be considered a first-trimester marker of hypertensive disorders of pregnancy.
Department of Public Health, State University of Ceará, Fortaleza, Brazil.|Science Health Department, Medicine Course, University of Fortaleza, Fortaleza, Brazil.
Sammya
S
Bezerra Maia E Holanda Moura
Department of Public Health, State University of Ceará, Fortaleza, Brazil.
Paulo Cesar
PC
Praciano
Department of Public Health, State University of Ceará, Fortaleza, Brazil.
Julio Augusto
JA
Gurgel Alves
Department of Obstetrics and Gynecology, Ribeirão Preto Medical School, University of São Paulo, São Paulo, Brazil.
Wellington P
WP
Martins
Department of Obstetrics, Paulista School of Medicine, São Paulo Federal University, São Paulo, Brazil.
Edward
E
Araujo Júnior
Department of Obstetrics and Gynecology, University of Melbourne, Royal Women's Hospital, Parkville, Victoria, Australia.|Pregnancy Research Center, Royal Women's Hospital, Parkville, Victoria, Australia.
Stefan C
SC
Kane
Department of Obstetrics and Gynecology, University of Melbourne, Royal Women's Hospital, Parkville, Victoria, Australia fabricio.costa@thewomens.org.au.|Pregnancy Research Center, Royal Women's Hospital, Parkville, Victoria, Australia fabricio.costa@thewomens.org.au.|Monash Ultrasound for Women, Melbourne, Victoria, Australia fabricio.costa@thewomens.org.au.
Fabrício
F
da Silva Costa
D000328:Adult; D005260:Female; D006801:Humans; D046110:Hypertension, Pregnancy-Induced / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D007668:Kidney / Q000098:blood supply / Q000000981:diagnostic imaging; D011237:Predictive Value of Tests; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011446:Prospective Studies; D012082:Renal Veins / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D015203:Reproducibility of Results; D018608:Ultrasonography, Doppler / Q000379:methods*; D055815:Young Adult
Doppler sonography; hypertension; obstetric ultrasound; preeclampsia; renal venous circulation