Ophthalmic artery Doppler in women with hypertensive disorders of pregnancy: relationship to blood pressure control and renal dysfunction at 6-9 weeks postnatally.

OBJECTIVE: To examine the postnatal course of the ophthalmic artery (OA) Doppler in women with hypertensive disorders of pregnancy (HDP) and evaluate the correlation between OA Dopplers and poor postnatal blood pressure control and renal dysfunction at 2-3 and 6-9 weeks postnatally.

METHODS: Prospective cohort study of women with singleton pregnancies with HDP in a tertiary Pregnancy Hypertension clinic. Three visits were included: 1) the last antenatal hypertension clinic visit within 2 weeks prior to delivery, 2) 2-3 weeks postnatally, 3) 6-9 weeks postnatally. At each visit, maternal demographics, medical history, blood pressure and maternal OA Dopplers were performed. In addition, antenatally, fetal growth and fetal Dopplers were examined and at 6-9 weeks postnatally, estimated glomerular filtration rate and proteinuria were quantified. Study participants were divided into four hypertension groups, according to the blood pressure changes with time during the three visits. For the postnatal visits, hypertension was defined as systolic blood pressure (SBP) ≥140 mmHg and / or diastolic(D) BP ≥ 90 mmHg or SBP ≥130 mmHg or DBP ≥ 80 mmHg whilst taking antihypertensives. Group 1 was hypertensive in all three visits, Group 2 was hypertensive in the first two visits but was normotensive in the third visit, Group 3 was hypertensive in visits one and three, but normotensive in visit two, and Group 4 was hypertensive in visit one but normotensive in visits two and three. The longitudinal changes of mean arterial pressure (MAP) and peak systolic velocity (PSV) 1, PSV2 and the ratio of PSV2 / PSV1 over the three time points were examined by a repeated measure, multilevel linear mixed-effects analysis, controlling for maternal age, booking weight and use of antihypertensives. In addition, we examined the longitudinal change of OA Dopplers in women with different degrees of postnatal blood pressure control and in those with and without renal dysfunction at 6-9 weeks' postnatally.

RESULTS: 108 women (86 new-onset and 22 chronic hypertension) were recruited into the study. When controlling for maternal age, booking weight and use of antihypertensive medication, a significant decline in Log10 MAP (p<0.001), Log10 PSV1 (p<0.01) and Log10 PSV 2 (p=0.01) was seen between visits 1 and 3. The Log10 PSVR did not change with time (p=0.06). When assessing OA Dopplers against hypertension group, Log10 PSV1 and Log10 PSV2 did not differ between the hypertension groups whilst group 4 had a lower Log10 PSVR compared to groups 1 (p<0.01), 2 (p=0.03) and 3 (p<0.01). When assessing renal dysfunction at 6-9 weeks postnatally, Log10 PSVR was lower in those without than with renal dysfunction (-0.021, p=0.01), whilst Log10 MAP, Log10 PSV1 and Log10 PSV2 values did not differ. The Log10 PSVR did not change with time and remained -0.12 (95%CI, -0.13 to -0.11) across the three visits.

CONCLUSIONS: In women with HDP, the OA-PSVR was significantly higher in those with labile or persistently raised blood pressure postnatally when compared to women whose blood pressure normalised. Similarly, the OA-PSVR at 6-9 weeks postnatally was significantly higher in women with renal dysfunction versus those without dysfunction. This article is protected by copyright. All rights reserved.