Evaluation of Hemodynamics in People With Untreated Preeclampsia Using Echocardiography

The goal of this observational trial is to determine the resting cardiac output (CO) using transthoracic echocardiography (TTE) in a cohort of people with untreated preeclampsia, and a cohort of healthy normotensive pregnant people.

This study seeks to evaluate cardiac output in people with untreated preeclampsia in a tertiary referral centre in the US. In doing so the investigators hope to better understand the underpinning of the pathophysiology of this condition and provide evidence for (or against) the new theory of the development of preeclampsia. The investigators also seek to examine CO changes at birth during cesarean delivery (CD) comparing healthy pregnant people with people with preeclampsia and further understand the changes in cardiac output (CO) after treatment with antihypertensive agents for preeclamptic patients so that the investigators may better rationale treatment with these agents and evaluate the changes that may occur at the time of CD and after cesarean birth in people with preeclampsia using TTE so that fluid therapy and blood pressure treatment can be prescribed based on hemodynamic findings. Further the investigators aim to imbed echocardiography into the management of people with preeclampsia and to determine the feasibility and long-term sustainability of conducting echocardiography studies in pregnant people with a multidisciplinary group at the Brigham and Women's Hospital Boston.

Eligibility Criteria:
Inclusion Criteria:

Preeclampsia Participant.

1. Preclampsia definition: People with preeclampsia will be recruited at the time of diagnosis or suspected diagnosis of preeclampsia, according to accepted definitions of preeclampsia. Preeclampsia with severe features will be defined using the American College of Obstetrics and Gynecology definition.
2. Nulliparous, singleton pregnancy,
3. ≥20 weeks gestation
4. without any preexisting cardiovascular, hepatic, or respiratory problems,
5. No preexisting uterine abnormality including benign tumors, or placental adhesive disorder,
6. Not in labor,
7. Not with prior to treatment for preeclampsia,
8. Body mass index ≤ 40 kg/m2, age 18 to 50 years.

Healthy Participant:

Healthy pregnant people will be defined as

1. American Society of Anesthesiologists (ASA) Classification II with no significant medical or surgical illness,
2. Nulliparous (first pregnancy beyond 20 week's gestation)
3. Non-smokers, singleton pregnancy
4. Not having ruptured membranes
5. No uterine abnormalities
6. No placentation abnormalities.
7. Not receiving any vasoactive medication including salbutamol
8. Not on thyroid replacement hormones

Exclusion Criteria:

Preeclampsia Participant:

1. Multiparous, multiple pregnancy,
2. Previous cardiovascular, hepatic or respiratory problems
3. Gestational diabetes,
4. Hemodynamic or neurologically unstable patient
5. Unable to tolerate a 30-minute ultrasound examination (TTE)
6. Age less than 18 or greater than 50 years
7. BMI \> 40 kg/m2,
8. Gestation \< 20 weeks.

Healthy Participant:

1. Current administration of vasoactive drugs including salbutamol
2. Current administration of thyroxine
3. Pre-existing or gestational diabetes
4. Tobacco use
5. Pre-existing or gestational hypertension or preeclampsia
6. Known uterine abnormality, in labor or ruptured membranes
7. Unable to tolerate a 30-minute ultrasound examination (TTE)
8. Age less than 18 or greater than 50 years
9. BMI \> 40 kg/m2,
10. Gestation \< 20 weeks.