Automated self-initiated blood pressure or 24-hour ambulatory blood pressure monitoring in pregnancy?

Post-partum maternal bradycardia: A case series and literature review

Background

Unlike tachyarrhythmias, which are common in pregnancy, there is a paucity of data regarding maternal bradycardias. Our objective was to describe the characteristics, associated conditions, and prognosis of women who develop bradycardia post-partum.

Method

We conducted a retrospective chart review of patients referred to the Obstetrical Medicine service at British Columbia Women's Hospital from January 2012 to May 2020 for post-partum maternal bradycardia.

Results

Twenty-four patients with post-partum bradycardia were included (age 34.2  ±  4.8 years; heart rate 40.4  ±  8.1 beats per minute; blood pressure 131/72 mm Hg). Sinus bradycardia (79.2%) was the most common rhythm. Dyspnea (29.4%) and chest pain (23.5%) were common symptoms. Mean time to resolution of bradycardia was 3.6  ±  3.8 days. Associated conditions potentially explaining the bradycardia were preeclampsia (54.1%), underlying (16.7%), medications (8.3%), and neuraxial anesthesia (8.3%).

Conclusions

Maternal bradycardia is an uncommon condition complicating the post-partum period, that is generally self-limiting, with the majority only require clinical observation.

Consistency among Office, Home, and Ambulatory Blood Pressure Values in Women with Chronic Hypertension and History of Eclampsia or Preeclampsia

Adequate control of blood pressure (BP) is essential to prevent complications in pregnant women with a history of eclampsia or pre-eclampsia. However, the importance of office (OBPM), home (HBPM), and ambulatory (ABPM) BP measurements for proper control and prognosis in high-risk pregnancy is unknown. The present study aimed to compare BP values obtained during these three different BP measurements in women with a history of eclampsia or pre-eclampsia. This study included 79 pregnant women with chronic hypertension and a documented history of eclampsia or pre-eclampsia in previous pregnancy/pregnancies. Every fifth week of the study, all participants underwent ABPM, HBPM and OBPM. BP values from the 10th, 25th, and 37th weeks of pregnancy were evaluated. Therapy was intended to meet the ABPM treatment goal of <130/80 mmHg. Day, night, and 24 h ABPM systolic BP values were lower than HBPM and OBPM values at each study visit. Night and 24 h ABPM diastolic BP values were lower than HBPM and OBPM values, while day 24 h ABPM values were slightly higher than HBPM and OBPM values. ABPM provides different BP values than OBPM and HBPM. Target BP for ABPM in high-risk pregnancy hypertension should be estimated based on the predictive value of adverse pregnancy outcomes.

Home blood pressure monitoring in the diagnosis and treatment of hypertension in pregnancy: a systematic review and meta-analysis

BACKGROUND

Home blood pressure monitoring is increasingly used for pregnant individuals; however, there are no guidelines on such monitoring in this population. We assessed current practices in the prescription and use of home blood pressure monitoring in pregnancy.

METHODS

We conducted a systematic review and meta-analysis of observational studies and randomized controlled trials (RCTs). We conducted a structured search through the MEDLINE (from 1946), Embase (from 1974) and CENTRAL (from 2018) databases up to Oct. 19, 2020. We included trials comparing office and home blood pressure monitoring in pregnant people. Outcomes included patient education, home blood pressure device, monitoring schedule, adherence, diagnostic thresholds for home blood pressure, and comparison between home and office measurements of blood pressure.

RESULTS

We included in our review 21 articles on 19 individual studies (1 RCT, 18 observational) that assessed home and office blood pressure in pregnant individuals (n = 2843). We observed variation in practice patterns in terms of how home monitoring was prescribed. Eight (42%) of the studies used validated home blood pressure devices. Across all studies, measurements were taken 3 to 36 times per week. Third-trimester home blood pressure corresponding to office blood pressure of 140/90 mm Hg after application of a conversion factor ranged from 118 to 143 mm Hg (systolic) and from 76 to 92 mm Hg (diastolic), depending on the patient population and methodology. Systolic and diastolic blood pressure values measured at home were lower than office values by 4 (95% confidence interval [CI] -6 to -3) mm Hg and 3 (95% CI -4 to -2) mm Hg, respectively.

INTERPRETATION

Many issues related to home blood pressure monitoring in pregnancy are currently unresolved, including technique, monitoring schedule and target values. Future studies should prioritize the use of validated home measuring devices and standardized measurement schedules and should establish treatment targets.

PROSPERO REGISTRATION

CRD42020147352.

How Do Home and Clinic Blood Pressure Readings Compare in Pregnancy?

Hypertensive disorders during pregnancy result in substantial maternal morbidity and are a leading cause of maternal deaths worldwide. Self-monitoring of blood pressure (BP) might improve the detection and management of hypertensive disorders of pregnancy, but few data are available, including regarding appropriate thresholds. This systematic review and individual patient data analysis aimed to assess the current evidence on differences between clinic and self-monitored BP through pregnancy. MEDLINE and 10 other electronic databases were searched for articles published up to and including July 2016 using a strategy designed to capture all the literature on self-monitoring of BP during pregnancy. Investigators of included studies were contacted requesting individual patient data: self-monitored and clinic BP and demographic data. Twenty-one studies that utilized self-monitoring of BP during pregnancy were identified. Individual patient data from self-monitored and clinic readings were available from 7 plus 1 unpublished articles (8 studies; n=758) and 2 further studies published summary data. Analysis revealed a mean self-monitoring clinic difference of ≤1.2 mm Hg systolic BP throughout pregnancy although there was significant heterogeneity (difference in means, I2 >80% throughout pregnancy). Although the overall population difference was small, levels of white coat hypertension were high, particularly toward the end of pregnancy. The available literature includes no evidence of a systematic difference between self and clinic readings, suggesting that appropriate treatment and diagnostic thresholds for self-monitoring during pregnancy would be equivalent to standard clinic thresholds.

Blood pressure self-monitoring in pregnancy: examining feasibility in a prospective cohort study

BACKGROUND

Raised blood pressure (BP) affects approximately 10% of pregnancies worldwide, and a high proportion of affected women develop pre-eclampsia. This study aimed to evaluate the feasibility of self-monitoring of BP in pregnancy in women at higher risk of pre-eclampsia.

METHODS

This prospective cohort study of self-monitoring BP in pregnancy was carried out in two hospital trusts in Birmingham and Oxford and thirteen primary care practices in Oxfordshire. Eligible women were those defined by the UK National Institute for Health and Care Excellence (NICE) guidelines as at higher risk of pre-eclampsia. A total of 201 participants were recruited between 12 and 16 weeks of pregnancy and were asked to take two BP readings twice daily three times a week through their pregnancy. Primary outcomes were recruitment, retention and persistence of self-monitoring. Study recruitment and retention were analysed with descriptive statistics. Survival analysis was used to evaluate the persistence of self-monitoring and the performance of self-monitoring in the early detection of gestational hypertension, compared to clinic BP monitoring. Secondary outcomes were the mean clinic and self-monitored BP readings and the performance of self-monitoring in the detection of gestational hypertension and pre-eclampsia compared to clinic BP.

RESULTS

Of 201 women recruited, 161 (80%) remained in the study at 36 weeks or to the end of their pregnancy, 162 (81%) provided any home readings suitable for analysis, 148 (74%) continued to self-monitor at 20 weeks and 107 (66%) at 36 weeks. Self-monitored readings were similar in value to contemporaneous matched clinic readings for both systolic and diastolic BP. Of the 23 who developed gestational hypertension or pre-eclampsia and self-monitored, 9 (39%) had a raised home BP prior to a raised clinic BP.

CONCLUSIONS

Self-monitoring of BP in pregnancy is feasible and has potential to be useful in the early detection of gestational hypertensive disorders but maintaining self-monitoring throughout pregnancy requires support and probably enhanced training.

A history of preeclampsia identifies women who have underlying cardiovascular risk factors

OBJECTIVE

The objective of this study was to prospectively assess physical and biochemical cardiovascular risk markers in women who had developed preeclampsia (PE) at 1 year postpartum.

STUDY DESIGN

Following an overnight fast, previously PE (n = 70) and normotensive women (n = 70) had weight and blood pressure recorded and levels of morning blood for insulin, glucose, C-reactive protein, lipids, cholesterol, and urine for microalbumin and creatinine measured. Body mass index, homeostatic model assessment index, and incidence of metabolic syndrome were determined.

RESULTS

At 1 year postpartum, markers of cardiovascular disease were different between the groups. There were also differences in the number of women with abnormal values. Mathematical modeling of cardiovascular event risk suggests that PE increases the risk by 2- to 3-fold; the risk was greatest for women with severe PE.

CONCLUSION

The development of PE is 1 of the earliest clinically identifiable markers of a woman's heightened risk of cardiovascular disease.

The natural history of white coat hypertension during pregnancy

OBJECTIVE

White coat hypertension (WCH) is a common phenomenon with a long term prognosis intermediate between those with true hypertension and true normotension. The natural history of this phenomenon throughout pregnancy remains unknown. We assessed the likelihood of women with an initial diagnosis of WCH developing pre-eclampsia (PE) as their pregnancy progressed.

DESIGN

Prospective observational study.

SETTING

St George Hospital, a teaching and University hospital.

POPULATION

Two hundred and forty-one pregnant women with an early pregnancy diagnosis of essential hypertension (EH).

METHODS

Eighty-six women had this diagnosis (EH) confirmed pre-pregnancy by 24-hour ambulatory blood pressure monitoring (ABPM) or repeated automated home blood pressure (BP) self-measurement. The remaining 155 underwent 24-hour ABPM in early pregnancy to establish their diagnosis. Women found to have WCH did not receive antihypertensives during their pregnancy, whereas those with confirmed EH received oxprenolol or methyldopa. Women with WCH had repeated 24-hour ABPM and/or BP assessments in a pregnancy day assessment unit until delivery.

MAIN OUTCOME MEASURE

The development of PE in women with WCH or EH.

RESULTS

The overall prevalence of WCH was 32%. Half retained this phenomenon throughout pregnancy and had good pregnancy outcomes. Forty percent developed (benign) gestational hypertension and also had good pregnancy outcomes while 8% developed proteinuric PE, significantly fewer than in women with confirmed EH (22%), P= 0.008. No BP parameter at study entry permitted discrimination between those women with WCH who retained this phenomenon and those who developed GH or PE.

CONCLUSION

WCH is a common phenomenon in pregnant women who appear to have EH according to routine BP measurement early in pregnancy. Antihypertensives may be withheld from this group initially and they can be advised they will have better pregnancy outcomes than women with true EH. However, continued monitoring throughout pregnancy remains important to detect the small group of white coat hypertensives who develop PE.