The Heart Outcomes in Pregnancy Expectations for Mom and Baby Study

The US is the only industrialized nation to experience a rise in maternal mortality over the last decade. Despite the Healthy People 2030 agenda target of reducing maternal mortality by 10%, rates in the United States are predicted to increase. Furthermore, maternal mortality disproportionately impacts Black, Hispanic, American Indian/Alaskan Native (AIAN), and Asian/Pacific Islander birthing people, who die at a rate that far greater than their White counterparts. Black birthing people are twice as likely to experience severe maternal morbidity (SMM) and 3-4X more likely to die, even after adjusting for demographic and hospital factors. Unfortunately, this gap is widening, with a 20% increase in death for Blacks as compared with a 5% rise in Whites over the last decade. Understanding contributors to adverse outcomes for marginalized birthing populations cannot solely be determined from retrospective chart adjudication and requires prospective evaluation to better understand patient and treatment factors contributing to maternal morbidity and mortality.

Despite affecting only 2-4% of pregnancies, cardiovascular disease (CVD) accounts for >30% of maternal deaths, making it a leading cause of maternal mortality for all birthing people and the number one cause in the Black population. Pregnant people with acquired and congenital heart disease experience the majority of CV-related morbidity and mortality, of which over three quarters have been deemed preventable. The prevalence of CVD is expected to grow as risk factors for CV-related death (obesity, advanced maternal age, hypertensive disorders, and preexisting heart disease) are rising dramatically in pregnant people, which disproportionately burdens marginalized populations. Provider-based factors are a leading cause of preventable morbidity, yet the lack of evidence-based guidelines, means of risk-stratifying pregnant people with CVD, or insight into how best to structure care limits the ability to improve maternal outcomes.

Mortality is not the only important outcome for pregnant people with CVD. For every maternal death, it is estimated that 100 people - 50,000 per year - will suffer severe maternal morbidity (SMM) during delivery, with significant costs to both their families and the economy. Adverse pregnancy outcomes (APOs) and neonatal adverse clinical events (NACEs), including pre-eclampsia, preterm delivery, fetal growth restriction, stillbirth and maternal hemorrhage, are all significantly more common in those with heart disease. Pregnant people who survive these events are more likely to suffer post-traumatic stress and depression, which can adversely impact mother-child bonding and long-term health. Importantly, there are no studies in this population evaluating quality of life, which cannot be measured using retrospective data.

To address the critical need for reversing the US trend in maternal morbidity and mortality, the Heart Outcomes in Pregnancy Expectations (HOPE) study will focus on the highest risk population, pregnant people with CVD. It will provide deeper insights into maternal risk factors, their association with care, and the influence of alternative structures of cardio-obstetric care with APO, MACE, and NACE outcomes. It is a multi-site, multidisciplinary prospective study at >30 cardio-obstetrics clinics throughout the US with a key secondary goal of better understanding racial disparities in care and outcomes. Not only will traditional APOs, MACE, and NACE events from presentation to 1-year after delivery be collected, generic and disease-specific quality of life will be measured as a way to evaluate their independent impact on outcomes.

Preliminary insights through our pilot program highlight the importance of better structures of care as a means of improving outcomes, which has previously been established in other clinical settings, but not in cardio-obstetrics care. The investigators have identified 6 key structures of care that have been variably adopted through the US and for which additional data to define their independent association with outcomes is needed.

These include:

1. multidisciplinary (OB/maternal-fetal medicine [MFM], cardiology, anesthesia, critical care, etc.) care teams;
2. a COB care coordinator;
3. coordinated inter-disciplinary patient evaluation;
4. team debriefing
5. the ability to perform high-risk deliveries in the ICU and
6. formalized warm hand offs to primary or sub-specialty care after delivery.

After adjusting for extensive patient factors associated with adverse outcomes, the independent association of these structures of care with outcomes will be estimated as a foundation for testing and disseminating those that are most effective.