Hydralazine vs nifedipine for acute hypertensive emergency in pregnancy: a randomized controlled trial

Pharmaceutical administration for severe hypertension during pregnancy: Network meta-analysis

Aims: To evaluate the efficacy of different pharmacologic treatment for severe hypertension during pregnancy. Methods: Two reviewers searched Ovid MEDLINE, Ovid EMbase, and the Cochrane Library for randomized clinical trials from the establishment of the database to 15 July 2021 that were eligible for inclusion and analyzed the pharmaceuticals used for severe hypertension in pregnancy. Results: 29 relevant trials with 2,521 participants were involved. Compared with diazoxide in rate of achieving target blood pressure, other pharmaceuticals, including epoprostenol (RR:1.58, 95%CI:1.01-2.47), hydralazine\dihydralazine (RR:1.57, 95%CI:1.07-2.31), ketanserin (RR:1.67, 95%CI:1.09-2.55), labetalol (RR:1.54, 95%CI:1.04-2.28), nifedipine (RR:1.54, 95%CI:1.04-2.29), and urapidil (RR:1.57, 95%CI:1.00-2.47), were statistically significant in the rate of achieving target blood pressure. According to the SUCRA, diazoxide showed the best therapeutic effect, followed by nicardipine, nifedipine, labetalol, and nitroglycerine. The three pharmaceuticals with the worst therapeutic effect were ketanserin, hydralazine, and urapidil. It is worth noting that the high ranking of the top two pharmaceuticals, including diazoxide and nicardipine, comes from extremely low sample sizes. Other outcomes were reported in the main text. Conclusion: This comprehensive network meta-analysis demonstrated that the nifedipine should be recommended as a strategy for blood pressure management in pregnant women with severe hypertension. Moreover, the conventional pharmaceuticals, including labetalol and hydralazine, showed limited efficacy. However, it was important to note that the instability of hydralazine reducing blood pressure and the high benefit of labetalol with high dosages intakes should also be of concern to clinicians.

Comparative efficacy and safety of oral nifedipine with other antihypertensive medications in the management of hypertensive disorders of pregnancy: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Hypertensive disorders of pregnancy are the most frequently occurring medical condition during pregnancy, resulting in fetal and/or maternal morbidity and mortality. This meta-analysis compared the efficacy and safety of nifedipine with other antihypertensive medications used in hypertensive disorders of pregnancy.

METHODOLOGY

A comprehensive search was performed using PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), and Google Scholar. The meta-analysis was carried out using Review Manager Software, and the pooled effect estimate was generated as standardized mean difference and odds ratio with 95% confidence interval and two-sided P -value.

RESULTS

The meta-analysis was comprised of 22 randomized control trials with 2595 participants. It was found that meantime and number of doses required to achieve target blood pressure were lower in the nifedipine group ( P  < 0.05). Even though it is statistically insignificant, fetal APGAR (Appearance, Pulse, Grimace, Activity, and Respiration) scores less than seven favors nifedipine intervention. Furthermore, none of the fetal or maternal secondary outcomes were found significant.

CONCLUSION

Nifedipine was found to be more effective than other antihypertensive medications to reduce blood pressure, particularly in patients with severe hypertension. However, future clinical studies, including real-world data are necessary to establish the safety profile of nifedipine concerning the fetal outcomes in hypertensive pregnant women.

A review on the clinical pharmacokinetics of hydralazine

INTRODUCTION

Hydralazine is a vasodilator used to treat hypertension, pre-eclampsia, and heart failure. The current article reviews the clinical pharmacokinetics (PK) of hydralazine, which can be useful for clinicians in optimizing its dose and dosing frequency to avoid adverse effects and unexpected interactions that could risk patients' lives.

AREAS COVERED

This review has summarized the PK parameters for hydralazine after performing an extensive literature search. It includes 20 publications that were selected after applying eligibility criteria out of a pool of literature that was searched using Google Scholar, PubMed, Cochrane Central, and EBSCO databases. The included studies consisted of concentration vs. time profiles of hydralazine. If the PK data were not tabulated in the given study, the concentration vs. time profiles were scanned for the extraction of the PK data. The PK parameters were calculated by applying a non-compartmental analysis (NCA).

EXPERT OPINION

The current review will aid clinicians in understanding hydralazine PK in different disease populations. This clinical PK data might also be helpful in the development of a pharmacokinetic model of hydralazine.

Gestational Hypertension and Preeclampsia: An Overview of National and International Guidelines

Importance

Gestational hypertension and preeclampsia are leading causes of maternal and perinatal morbidity and mortality worldwide. Τhe lack of effective screening and management policies appears to be one of the main reasons.

Objective

The aim of this study was to review and compare recommendations from published guidelines on these common pregnancy complications.

Evidence Acquisition

A descriptive review of guidelines from the National Institute for Health and Care Excellence, the Society of Obstetric Medicine of Australia and New Zealand, the International Society of Hypertension, the International Society for the Study of Hypertension in Pregnancy, the European Society of Cardiology, the International Federation of Gynecology and Obstetrics, the Society of Obstetricians and Gynaecologists of Canada, the American College of Obstetricians and Gynecologists, the International Society of Ultrasound in Obstetrics and Gynecology, the World Health Organization, and the US Preventive Services Task Force on gestational hypertension and preeclampsia was carried out.

Results

There is an overall agreement that, in case of suspected preeclampsia or new-onset hypertension, blood and urine tests should be carried out, including dipstick test for proteinuria, whereas placental growth factor-based testing is only recommended by the National Institute for Health and Care Excellence and the European Society of Cardiology. In addition, there is a consensus on the recommendations for the medical treatment of severe and nonsevere hypertension, the management of preeclampsia, the appropriate timing of delivery, the optimal method of anesthesia and the mode of delivery, the administration of antenatal corticosteroids and the use of magnesium sulfate for the treatment of eclamptic seizures, the prevention of eclampsia in cases of severe preeclampsia, and the neuroprotection of preterm neonates. The reviewed guidelines also state that, based on maternal risk factors, pregnant women identified to be at high risk for preeclampsia should receive low-dose aspirin starting ideally in the first trimester until labor or 36 to 37 weeks of gestation, although the recommended dose varies between 75 and 162 mg/d. Moreover, most guidelines recommend calcium supplementation for the prevention of preeclampsia and discourage the use of other agents. However, controversy exists regarding the definition and the optimal screening method for preeclampsia, the need for treating mild hypertension, the blood pressure treatment targets, and the postnatal blood pressure monitoring.

Conclusions

The development and implementation of consistent international protocols will allow clinicians to adopt effective universal screening, as well as preventive and management strategies with the intention of improving maternal and neonatal outcomes.

Pulse pressure as a predictor of response to treatment for severe hypertension in pregnancy

BACKGROUND

Pulse pressure is a proposed means of tailoring antihypertensive therapy for treatment of acute-onset, severe hypertension in pregnancy.

OBJECTIVE

This study aimed to determine whether pulse pressure predicts response to the various first-line antihypertensive medications.

STUDY DESIGN

This is a retrospective cohort study from a single academic tertiary care center between 2015 and 2018. Patients were screened for inclusion if they had severe hypertension (defined as systolic blood pressure of ≥160 mm Hg or diastolic blood pressure of ≥110 mm Hg) lasting at least 15 minutes and were initially treated with intravenous labetalol, intravenous hydralazine, or immediate-release oral nifedipine. If a patient had multiple episodes of acute treatment during the pregnancy, only one episode was included in the analysis. The primary outcome was time to resolution (in minutes) of severe hypertension. To adjust for factors that may have affected time to resolution, we first compared baseline characteristics on the basis of the antihypertensive agent received. We then assessed the association between baseline characteristics and resolution of severe hypertension within 60 minutes of treatment. Regression analysis incorporated pulse pressure and antihypertensive agents into a model to predict resolution within 60 minutes of onset of severe hypertension.

RESULTS

A total of 479 women hospitalized with severe maternal hypertension met the inclusion criteria. Hydralazine was the initial antihypertensive agent administered to 113 women, whereas 233 received labetalol, and 133 received nifedipine. Those who initially received nifedipine had a shorter mean time to resolution of severe hypertension (32.6 minutes vs 46.3 for hydralazine and 50.3 for labetalol; P<.01) and were more likely to have resolution of severe hypertension within 60 minutes (91.0% vs 77.9% for hydralazine and 76.8% for labetalol; P<.01). Nifedipine also resulted in a lower mean posttreatment blood pressure. Regression analysis revealed that a lack of resolution of severe hypertension within 60 minutes was independently associated with 2 measures of hypertension severity (mean arterial pressure of ≥125 mm Hg and the need for ≥2 doses of medication) and pulse pressure of >75 mm Hg at the time of treatment, initial treatment with labetalol, and gestational age of <37 weeks at the time of the hypertensive event (or at delivery if treatment was after delivery). The model's bias-corrected bootstrapped area under the receiver operating characteristic curve was 0.85 (95% confidence interval, 0.79-0.88). Interaction terms between pulse pressure and each antihypertensive agent were not significant and therefore not incorporated into the final model.

CONCLUSION

Pulse pressure did not predict response to the various first-line antihypertensive agents. Initial treatment with oral nifedipine was associated with a higher likelihood of resolution of severe hypertension within 60 minutes of treatment than with intravenous labetalol.

Neurovascular dysfunctions in hypertensive disorders of pregnancy

Hypertensive disorders in pregnancy pose a huge challenge to the socioeconomic stability of a community; being a major cause of maternal and neonatal morbidity and mortality during delivery. Although there have been recent improvements in management strategies, still, the diversified nature of the underlying pathogenesis undermines their effectiveness. Generally, these disorders are categorized into two; hypertensive disorders of pregnancy with proteinuria (pre-eclampsia and eclampsia) and hypertensive disorders of pregnancy without proteinuria (gestational and chronic hypertension). Each of these conditions may present with unique characteristics that have interwoven symptoms. However, the tendency of occurrence heightens in the presence of any pre-existing life-threatening condition(s), environmental, and/or other genetic factors. Investigations into the cerebrovascular system demonstrate changes in the histoarchitectural organization of neurons, the proliferation of glial cells with an associated increase in inflammatory cytokines. These are oxidative stress indicators which impose a deteriorating impact on the structures that form the neurovascular unit and the blood-brain barrier (BBB). Such a pathologic state distorts the homeostatic supply of blood into the brain, and enhances the permeability of toxins/pathogens through a process called hyperperfusion at the BBB. Furthermore, a notable aspect of the pathogenesis of hypertensive disorders of pregnancy is endothelial dysfunction aggravated when signaling of the vasoprotective molecule, nitric oxide, amongst other neurotransmitter regulatory activities are impaired. This review aims to discuss the alterations in cerebrovascular regulation that determine the incidence of hypertension in pregnancy.

The flipside of hydralazine in pregnancy: A systematic review and meta-analysis

The present systematic review and meta-analysis investigated the effects of hydralazine compared with other antihypertensive drugs in maternal, perinatal and neonatal outcomes of pregnant women with hypertensive disorders. Twenty studies with 1283 participants were included. Of them, 626 received hydralazine and 657 other antihypertensive treatments, such as labetalol, nifedipine, ketanserin, diazoxide, urapidil, isradipine and epoprostenol. Women receiving hydralazine had higher heart rate (WMD: 13.4, 95%CI: 0.1 to 26.8 beats/min), increased number of adverse effects (RR: 1.21, 95%CI: 1.01 to 1.45) and gave birth to neonates of lower birthweight (WMD: 13.4, 95%CI: 0.1 to 26.8 beats/min) compared with other antihypertensive treatments at the end of follow-up. When studies, which used antihypertensive agents that are no longer indicated for hypertension in pregnancy, were excluded in the sensitivity analyses, hydralazine found not to have a statistically significant difference compared with labetalol and nifedipine regarding the reduction of maternal blood pressure (WMD: 1.72, 95%CI: -1.47 to 4.9 mmHg for systolic, WMD: 0.26, 95%CI: -1.75 to 2.28 mmHg for diastolic), maternal heart rate (WMD: 13.56, 95%CI: -5.62 to 32.74 beats/min), low birthweight (WMD: -88.62, 95%CI: -243.24 to 66 beats/min) and adverse events (RR: 1.19, 95%CI: 0.99 to 1.43). Hydralazine seems not to be inferior compared to labetalol and nifedipine for safety and efficacy.

Hypertension Drug Therapy

Hypertension is still the number one global killer. No matter what causes are, lowering blood pressure can significantly reduce cardiovascular complications, cardiovascular death, and total death. Unfortunately, some hypertensive individuals simply do not know having hypertension. Some knew it but either not being treated or treated but blood pressure does not achieve goal. The reasons for inadequate control of blood pressure are many. One important reason is that we are not very familiar with antihypertensive agents and less attention has been paid to comorbidities, complications as well as the hypertension-modified target organ damage in patients with hypertension. The right antihypertensive drug was not given to the right hypertensive patients at right time. This reviewer studied comprehensively the literature, hopefully that the review will help improve antihypertensive drug selection and antihypertensive therapy.

Maternal cardiac parameters can help in differentiating the clinical profile of preeclampsia and in predicting progression from mild to severe forms

BACKGROUND

A primary role of maternal heart dysfunction in the pathophysiology of preeclampsia had been previously advocated although if contradictory results have been reported.

OBJECTIVES

The objectives of the study were to describe maternal hemodynamic parameters according to 2 main preeclampsia phenotypes and to investigate whether cardiac findings may be helpful in characterizing the severity and the progression of the disease.

STUDY DESIGN

This was a prospective cohort study. We used an ultrasonic cardiac output monitor system to compare the hemodynamic parameters of women with preeclampsia with a group of healthy normotensive women enrolled as controls with a ratio of 1:2. Cardiac output, systemic vascular resistance, and stroke volume were compared among controls and preeclamptic women who were grouped in accordance to the following characteristics: early preeclampsia (<34 weeks' gestation) vs late preeclampsia onset (≥34 weeks' gestation); preeclampsia associated with appropriate for gestational age or small-for-gestational-age newborns. Hemodynamic characteristics were also compared between preeclamptic women with a mild form vs those who progressed toward a severe form.

RESULTS

A total of 38 preeclamptic women and 61 normotensive women were included in the study. Both cases of preeclampsia associated with small-for-gestational-age neonates as those with normal-sized ones showed higher systemic vascular resistance compared with the control group (respectively, 1580.6 ± 483.2 vs 1479.1 ± 433.3 vs 1105.3 ± 293.1; P < .0001), while a lower cardiac output was reported only for preeclamptic women with small-for-gestational-age neonates compared with controls (5.7 ± 1.5 vs 6.5 ± 1.3; P = .02). Maternal cardiac parameters were comparable between these 2 groups of preeclamptic women (small-for-gestational-age vs appropriate-for-gestational-age preeclampsia) with the exception of a lower stroke volume in the former one (64.8 ± 24.4 vs 75.2 ± 17.8; P = .04). Similarly, women with both early and late preeclampsia showed higher systemic vascular resistance compared with controls (1559.5 ± 528.3 vs 1488.5 ± 292.9 vs 1105.3 ± 293.1, respectively; P < .001), while a lower cardiac output was noted only in the early-onset group compared with controls (5.5 ± 1.2 P = .02). Maternal cardiac findings were similar between women with early vs late-onset preeclampsia. Hemodynamic parameters are significantly different between those women with mild preeclampsia who remained stable compared with those who progressed toward a severe disease. Cardiac output Z-score, systemic vascular resistance Z-score, and uterine arteries' pulsatility index Z-score showed similar sensitivity (80% vs 75% vs 80%, respectively) and specificity (73% vs. 73% vs 74%, respectively), while the association of systemic vascular resistance Z-score and uterine arteries pulsatility index Z-score showed a sensitivity of 95% and a specificity of 80% (area under the curve, 0.90) in predicting evolution toward severe forms.

CONCLUSION

Evaluation of maternal cardiovascular system could help clinician in defining a subset of preeclamptic patients with more profound placental impairment and might predict the likelihood of progression toward a severe condition in cases with a mild preeclampsia at clinical onset.

Methyldopa versus nifedipine or no medication for treatment of chronic hypertension during pregnancy: A multicenter randomized clinical trial

OBJECTIVE

To assess the maternal and fetal outcome in women with mild to moderate chronic hypertension on antihypertensive drug (methyldopa or nifedipine) therapy compared to no medication.

METHODS

This multicenter randomized clinical trial was conducted at Menoufia University hospital, Shibin El-kom Teaching hospital and 11 Central hospitals at Menoufia governorate, Egypt.490 pregnant women with mild to moderate chronic hypertension were randomized into three groups; methyldopa group (n = 166), nifedipine group (n = 160) and control or no medication group (n = 164) who were followed from the beginning of pregnancy till the end of puerperium to record maternal and fetal outcome.

RESULTS

Mothers in the control (no medication) group were more prone for the development of severe hypertension, preeclampsia, renal impairment, ECG changes, placental abruption and repeated hospital admissions (p < 0.001) when compared to mothers in both treatment groups (methyldopa and nifedipine). Neonates in the control (no medication) group were more prone for prematurity and admission to neonatal ICU (p < 0.001).

CONCLUSION

Antihypertensive drug therapy is advisable in mild to moderate chronic hypertension during pregnancy to decrease maternal and fetal morbidity. When considering which agents to use for treatment, oral methyldopa and nifedipine are valid options.

Uterine and fetal placental Doppler indices are associated with maternal cardiovascular function

BACKGROUND

The mechanism underlying fetal-placental Doppler index changes in preeclampsia and/or fetal growth restriction are unknown, although both are associated with maternal cardiovascular dysfunction.

OBJECTIVE

We sought to investigate whether there was a relationship between maternal cardiac output and vascular resistance and fetoplacental Doppler findings in healthy and complicated pregnancy.

STUDY DESIGN

Women with healthy pregnancies (n=62), preeclamptic pregnancies (n=13), preeclamptic pregnancies with fetal growth restriction (n=15), or fetal growth restricted pregnancies (n=17) from 24-40 weeks gestation were included. All of them underwent measurement of cardiac output with the use of an inert gas rebreathing technique and derivation of peripheral vascular resistance. Uterine and fetal Doppler indices were recorded; the latter were z scored to account for gestation. Associations were determined by polynomial regression analyses.

RESULTS

Mean uterine artery pulsatility index was higher in fetal growth restriction (1.37; P=.026) and preeclampsia+fetal growth restriction (1.63; P=.001) but not preeclampsia (0.92; P=1) compared with control subjects (0.8). There was a negative relationship between uterine pulsatility index and cardiac output (r²=0.101; P=.025) and umbilical pulsatility index z score and cardiac output (r²=0.078; P=.0015), and there were positive associations between uterine pulsatility index and peripheral vascular resistance (r²=0.150; P=.003) and umbilical pulsatility index z score and peripheral vascular resistance (r²= 0.145; P=.001). There was no significant relationship between cardiac output and peripheral vascular resistance with cerebral Doppler indices.

CONCLUSION

Uterine artery Doppler change is abnormally elevated in fetal growth restriction with and without preeclampsia, but not in preeclampsia, which may explain the limited sensitivity of uterine artery Doppler changes for all these complications when considered in aggregate. Furthermore, impedance within fetoplacental arterial vessels is at least, in part, associated with maternal cardiovascular function. This relationship may have important implications for fetal surveillance and would inform therapeutic options in those pathologic pregnancy conditions currently, and perhaps erroneously, attributed purely to placental maldevelopment. Uterine and fetal placental Doppler indices are associated significantly with maternal cardiovascular function. The classic description of uterine and fetal Doppler changes being initiated by placental maldevelopment is a less plausible explanation for the pathogenesis of the conditions than that relating to maternal cardiovascular changes.

State-of-the-Art Diagnosis and Treatment of Hypertension in Pregnancy

Hypertension complicates up to 10% of pregnancies worldwide. Pregnancy hypertension is defined as systolic blood pressure (BP) equal to or greater than 140 mm Hg or diastolic BP equal to or greater than 90 mm Hg, usually on the basis of measurements in office/clinic settings and using various BP devices. Hypertensive disorders of pregnancy are classified into (1) chronic hypertension diagnosed before pregnancy or before 20 weeks' gestation, (2) gestational hypertension diagnosed at equal to or greater than 20 weeks, or (3) preeclampsia, defined restrictively as gestational hypertension with proteinuria or broadly as gestational hypertension with proteinuria or an end-organ manifestation consistent with preeclampsia. Absolute BP values equal to or greater than 140/90 mm Hg are associated with increased maternal and perinatal risks, particularly with preeclampsia. This review focuses on antihypertensive therapy of hypertensive disorders of pregnancy as a specific management strategy. Underpinning this therapy is the need for accurate measurement of BP, agreed-upon classification of pregnancy hypertension, agreed-upon BP thresholds for enhanced surveillance and antihypertensive treatment, and collaborative teamwork in management. Challenges relate to the methodology of studies on which care is based, as well as aspects of the care itself, particularly the unregulated use of home BP monitoring. Pitfalls include the unsubstantiated belief that nifedipine and magnesium sulfate cannot be used together and the perception that severe hypertension and nonsevere hypertension are separate entities rather than lying along a spectrum of BP values. The following must be addressed by future research: guidance for nuanced care as women transition between severe and nonsevere hypertension, personalized antihypertensive therapy, and incorporation of women's values into research priorities and clinical practice when antihypertensive care is chosen.

Drugs for treating severe hypertension in pregnancy: a network meta-analysis and trial sequential analysis of randomized clinical trials

AIMS

Several antihypertensive drugs are used in the treatment of severe hypertension in pregnancy. The present study is a network meta-analysis comparing the efficacy and safety of these drugs.

METHODS

Electronic databases were searched for randomized clinical trials comparing drugs used in the treatment of severe hypertension in pregnancy. The number of women achieving the target blood pressure (BP) was the primary outcome. Doses required and time taken for achieving the target BP, failure rate, and incidences of maternal tachycardia, palpitation, hypotension, headache, and neonatal death and stillbirth were the secondary outcomes. Mixed treatment comparison pooled estimates were generated using a random-effects model. Odds ratios for the categorical and mean difference for the numerical outcomes were the effect estimates.

RESULTS

Fifty-one studies were included in the systematic review and 46 in the meta-analysis. No significant differences in the number of patients achieving target BP was observed between any of the drugs. Diazoxide [-15 (-20.6, -9.4)], nicardipine [-11.8 (-22.3, -1.2)], nifedipine/celastrol [-19.3 (-27.4, -11.1)], nifedipine/vitamin D [-17.1 (-25.7, -9.7)], nifedipine/resveratrol [-13.9 (-22.6, -5.2)] and glyceryl trinitrate [-33.8 (-36.7, -31)] were observed to achieve the target BP (in minutes) more rapidly than hydralazine. Nifedipine required fewer doses than hydralazine for achieving the target BP. Glyceryl trinitrate and labetalol were associated with fewer incidences of tachycardia and palpitation respectively than hydralazine. Trial sequential analysis concluded adequate evidence for hydralazine and nifedipine compared with labetalol. Moderate quality of evidence was observed for direct comparison estimate between labetalol and hydralazine but was either low or very low for other comparisons.

CONCLUSION

The present evidence suggests similar efficacy between nifedipine, hydralazine and labetalol in the treatment of severe hypertension in pregnancy. Subtle differences may exist in their safety profile. The evidence is inadequate for other drugs.

An Updated Review of Hypertensive Emergencies and Urgencies

A hypertensive crisis is an abrupt and severe rise in the arterial blood pressure (BP) occurring either in patients with known essential or secondary hypertension, or it may develop spontaneously. The most frequent cause for the severe and sudden increase in BP is inadequate dosing or stopping antihypertensive treatment in hypertensive patients. Severe hypertension can be defined as either a hypertensive emergency or an urgency, depending on the existence of organ damage. In hypertensive urgencies, there are no signs of acute end-organ damage, and orally administered drugs might be sufficient. In hypertensive emergencies, signs of acute end-organ damage are present, and in these cases, quickly-acting parenteral drugs must be used. The prompt recognition, assessment, and treatment of hypertensive urgencies and emergencies can decrease target organ damage and mortality. In this review, the definitions and therapeutic recommendations in a hypertensive crisis are presented in the light of the 2017 ACC/AHA Hypertension Guidelines.

Focused Update on Pharmacologic Management of Hypertensive Emergencies

PURPOSE OF REVIEW

Hypertensive emergency is defined as a systolic blood pressure > 180 mmHg or a diastolic blood pressure > 120 mmHg with evidence of new or progressive end-organ damage. The purpose of this paper is to review advances in the treatment of hypertensive emergencies within the last 5 years.

RECENT FINDINGS

New literature and recommendations for managing hypertensive emergencies in the setting of pregnancy, stroke, and heart failure have been published. Oral nifedipine is now considered an alternative first-line therapy, along with intravenous hydralazine and labetalol for women presenting with pre-eclampsia. Clevidipine is now endorsed by guidelines as a first-line treatment option for blood pressure reduction in acute ischemic stroke and may be considered for use in intracranial hemorrhage. Treatment of hypertensive heart failure remains challenging; clevidipine and enalaprilat can be considered for use in this population although data supporting their use remains limited.

Early and late preeclampsia are characterized by high cardiac output, but in the presence of fetal growth restriction, cardiac output is low: insights from a prospective study

BACKGROUND

Preeclampsia and fetal growth restriction are considered to be placentally mediated disorders. The clinical manifestations are widely held to relate to gestation age at onset with early- and late-onset preeclampsia considered to be phenotypically distinct. Recent studies have reported conflicting findings in relation to cardiovascular function, and in particular cardiac output, in preeclampsia and fetal growth restriction.

OBJECTIVE

We conducted this study to examine the possible relation between cardiac output and peripheral vascular resistance in preeclampsia and fetal growth restriction.

STUDY DESIGN

We investigated maternal cardiovascular function in relation to clinical subtype in 45 pathological pregnancies (14 preeclampsia only, 16 fetal growth restriction only, 15 preeclampsia and fetal growth restriction) and compared these with 107 healthy person observations. Cardiac output was the primary outcome measure and was assessed using an inert gas-rebreathing method (Innocor), from which peripheral vascular resistance was derived; arterial function was assessed by Vicorder, a cuff-based oscillometric device. Cardiovascular parameters were normalized for gestational age in relation to healthy pregnancies using Z scores, thus allowing for comparison across the gestational range of 24-40 weeks.

RESULTS

Compared with healthy control pregnancies, women with preeclampsia had higher cardiac output Z scores (1.87 ± 1.35; P = .0001) and lower peripheral vascular resistance Z scores (-0.76 ± 0.89; P = .025); those with fetal growth restriction had higher peripheral vascular resistance Z scores (0.57 ± 1.18; P = .04) and those with both preeclampsia and fetal growth restriction had lower cardiac output Z scores (-0.80 ± 1.3 P = .007) and higher peripheral vascular resistance Z scores (2.16 ± 1.96; P = .0001). These changes were not related to gestational age of onset. All those affected by preeclampsia and/or fetal growth restriction had abnormally raised augmentation index and pulse wave velocity. Furthermore, in preeclampsia, low cardiac output was associated with low birthweight and high cardiac output with high birthweight (r = 0.42, P = .03).

CONCLUSION

Preeclampsia is associated with high cardiac output, but if preeclampsia presents with fetal growth restriction, the opposite is true; both conditions are nevertheless defined by hypertension. Fetal growth restriction without preeclampsia is associated with high peripheral vascular resistance. Although early and late gestation preeclampsias are considered to be different diseases, we show that the hemodynamic characteristics of preeclampsia were unrelated to gestational age at onset but were strongly associated with the presence or absence of fetal growth restriction. Fetal growth restriction more commonly coexists with preeclampsia at early gestation, thus explaining the conflicting results of previous studies. Furthermore, antihypertensive agents act by reducing cardiac output or peripheral vascular resistance and are administered without reference to cardiovascular function in preeclampsia. The underlying pathology (preeclampsia, fetal growth restriction, preeclampsia and fetal growth restriction) defines cardiovascular phenotype, providing a rational basis for choice of therapy in which high or low cardiac output or peripheral vascular resistance is the predominant feature.