Kevin Harrington

Transvaginal Doppler ultrasound of the uteroplacental circulation in the early prediction of pre‐eclampsia and intrauterine growth retardation

Objective To evaluate the predictive value of transvaginal Doppler ultrasound studies of the uterine and umbilical arteries in early pregnancy, in identifying pregnant women at risk of subsequently developing pre‐eclampsia, or the delivery of a small for gestational age infant.

Doppler fetal circulation in pregnancies complicated by pre‐eclampsia or delivery of a small for gestational age baby: 2. Longitudinal analysis

Objective To observe the longitudinal changes in growth, and associated Doppler measurements, of the fetal circulation in pregnancies with a normal outcome and those complicated by pre‐eclampsia, birth of a small for gestational age baby, or a combination of these complications.

The value of uterine artery Doppler in the prediction of uteroplacental complications in multiparous women

To investigate the value of second‐trimester uterine artery Doppler in the prediction of complications resulting from uteroplacental insufficiency in low‐ and high‐risk multiparous women.

First-trimester markers for the prediction of pre-eclampsia in women with a-priori high risk

To investigate the predictive value of the combination of first‐trimester serum placental protein 13 (PP13), uterine artery Doppler pulsatility index (PI) and pulse wave analysis (augmentation index at a heart rate of 75 beats per min (AIx‐75)), and to evaluate concurrent and contingent strategies using this combination for assessing the risk of pre‐eclampsia in high‐risk women.

First trimester maternal serum placental protein 13 for the prediction of pre-eclampsia in women with a priori high risk.

To evaluate whether first trimester maternal serum PP13 can predict pre‐eclampsia among women with a priori high risk.

A prospective management study of slow‐release aspirin in the palliation of uteroplacental insufficiency predicted by uterine artery Doppler at 20 weeks

Objective  To investigate the effect of low‐dose, slow‐release aspirin in reducing the incidence and/or severity of pregnancy complications in women identified as high risk of developing problems associated with uteroplacental insufficiency, namely pre‐eclampsia or delivering a small‐for‐gestational age (SGA) baby.

Pulse wave analysis: a preliminary study of a novel technique for the prediction of pre-eclampsia

Objective  To investigate whether first‐trimester arterial pulse wave analysis (PWA) can predict pre‐eclampsia.

Antihypertensive Therapy and Central Hemodynamics in Women With Hypertensive Disorders in Pregnancy

OBJECTIVE: To estimate the changes in central hemodynamics features of pregnant women presenting with hypertensive disorders and to analyze the effects of standard antihypertensive treatment on maternal central hemodynamics. METHODS: Applanation tonometry was used to record the radial artery pulse waveform in 80 women presenting with preeclampsia or gestational hypertension and 80 normotensive controls matched for gestational age. In each case, an averaged aortic waveform was derived and analyzed to calculate augmentation pressure and augmentation index at heart rate 75 beats per minute (bpm). RESULTS: In women with preeclampsia and gestational hypertension, both augmentation pressure (P<.001 and P<.05, respectively) and augmentation index at heart rate 75 bpm (P<.001 and P<.001, respectively) were significantly higher than in controls. Augmentation pressure and augmentation index at heart rate 75 bpm were significantly higher in early- compared with late-onset preeclampsia (P<.001) and in severe compared with mild preeclampsia (P<.001). Antihypertensive therapy with alpha methyldopa resulted in a significant fall in both augmentation pressure and augmentation index at heart rate 75 bpm in preeclampsia (P<.001) but not in gestational hypertension. CONCLUSION: Arterial stiffness is increased in women with hypertensive disorders of pregnancy compared with normotensive controls. In preeclampsia, vascular stiffness was significantly improved by antihypertensive treatment with alpha methyldopa, but remained higher than in normotensive controls. LEVEL OF EVIDENCE: II

Pulse Wave Analysis in Normal Pregnancy: A Prospective Longitudinal Study

Background Outside pregnancy, arterial pulse wave analysis provides valuable information in hypertension and vascular disease. Studies in pregnancy using this technique show that vascular stiffness is raised in women with established pre-eclampsia. We aimed to establish normal ranges for parameters of pulse wave analysis in normal pregnancy and to compare different ethnic groups. Methodology/Principal Findings This prospective study was conducted at The Homerton University Hospital, London between January 2006 and March 2007. Using applanation tonometry, the radial artery pulse waveform was recorded and the aortic waveform derived. Augmentation pressure (AP) and Augmentation Index at heart rate 75/min (AIx-75), measures of arterial stiffness, were calculated. We recruited 665 women with singleton pregnancies. Women who developed pre-eclampsia (n = 24, 3.6%) or gestational hypertension (n = 36, 5.4%) were excluded. We also excluded 47 women with other pregnancy complications or incomplete follow-up, leaving 541 healthy normotensive pregnant women for subsequent analysis. In the overall group of 541 women, there were no significant changes in AP or AIx-75 as pregnancy progressed. In 45 women followed longitudinally, AP and AIx-75 fell significantly from the first to the second trimester, then rose again in the third (P<0.001). The two main ethnic groups represented were Caucasian (n = 229) and Afrocaribbean (n = 216). There were no significant differences in AP or AIx-75 in any trimester between these two ethnic groups. Conclusions This study is the largest to date of pulse wave analysis in normal pregnancy, the first to report on a subset of women studied longitudinally, and the first to investigate the effect of ethnicity. These data provide the foundation for further investigation into the potential role of this technique in vascular disorders in pregnancy.

Obstetric outcome in women who present with a reduction in fetal movements in the third trimester of pregnancy

A complaint of decreased fetal movements is a common indication for the assessment of fetal well being. The aim of this study was to review the outcome of a group of women whose primary indication for referral was decreased fetal movements. Over a 20 month period, 435 patients were seen in the fetal assessment unit of an inner London teaching hospital, following a primary complaint of reduced fetal movements. Investigations included: the fetal abdominal circumference (AC), amniotic fluid volume (AFV), the umbilical artery pulsatility index (UAPI) derived from Doppler ultrasound waveforms and a computerised analysis of fetal heart rate (FHR) recordings or cardiotocograph (CTG). Outcome measures were: gestational age at delivery, Apgar score < 7 at 5 minutes, admission to the Special Care Baby Unit (SCBU), the need for delivery by an emergency cesarean section for fetal compromise (CSFC), and any perinatal deaths. A comparison of actual versus expected outcome for women with decreased fetal movement revealed the following relative risks, with the 95% confidence intervals (CI) in brackets; low 5 minute Apgar score 0.03 vs. 0.05 expected (CI = 0.01, 0.05), SCBU admission, 0.06 vs. 0.07 (0.04, 0.08), and preterm delivery, 0.08 vs. 0.11 (0.05, 0.10). Cesarean sections for fetal compromise, 0.07 vs. 0.053 (0.050-0.096). The addition of FHR monitoring to standard ultrasound assessment of well being did not appear to confer any added benefit. There were no fetal deaths. The outcome for pregnancies where the mother presents with decreased fetal movements in the third trimester is comparable with the outcome for the general population.