Valvular Heart Disease and a Pregnancy-Associated Death

Abstract

Managing pregnancies in patients with prosthetic heart valves presents challenges including recurrent arrhythmia, bleeding, thrombosis, and infection. We present a woman with valvular heart disease and paroxysmal atrial arrhythmias who died after pregnancy and examine how Maternal Mortality Review Committees address areas to improve maternal outcomes.

Graphical Abstract

A patient with a prosthetic valve replacement and paroxysmal arrhythmias discovered she was pregnant. Comorbidity included hypertension and morbid obesity. She was first evaluated late second trimester at which time transthoracic echo showed normal left ventricular and prosthetic function. Warfarin was switched to low–molecular weight heparin, which was stopped in anticipation of delivery. Delivery was complicated by a hemorrhage requiring transfusion. She was discharged on low–molecular weight heparin. One week postpartum she developed increasing abdominal pain, presenting to an emergency department at 2 weeks postpartum with fever, continued pain, a malodorous discharge, and an elevated white blood cell count. A subacute hematoma was present. Subsequent course included bacteremia, endocarditis, and multiorgan failure. She died almost 1-month postpartum. An autopsy confirmed infectious endocarditis and uterine abscess.

Take-Home Messages

• •MMRCs are multidisciplinary groups that convene at the state or local level to comprehensively review pregnancy-associated deaths during or within 1 year of the end of pregnancy. They have access to both clinical and nonclinical information.
• •Based on these reviews, MMRCs determine the underlying reason for the death, identify contributing factors, and assess whether the death could have been prevented.
• •This case highlights the importance of maternal mortality review in defining actionable changes at multiple levels (patient, provider, hospital/facility, community, and systems) that promote improved maternal outcomes for patients with pregnancy-associated cardiovascular disease.

Question 1: What is this patient’s event risk with pregnancy?

The most commonly used tools to assess pregnancy risk are the modified World Health Organization classification scheme and CARPREG II (Cardiac Problems in Pregnancy Study II) tool. This patient’s risk of events is shown in Figure 1. The modified World Health Organization risk stratification scheme is lesion specific. A patient with a tissue bioprosthetic valve is class II-III and a mechanical prosthesis is class III. Event rates are high in the presence of a valve replacement, but mortality is low.^1,2 CARPREG II extrapolates from 10 maternal risk predictors to predict adverse outcomes (4 lesion specific, 5 general, and late presentation). The estimated event rate is 22% with a bioprosthesis, but 41% with a mechanical prosthesis. Estimated mortality rate is similar (0.3%).³ Mortality rate in the European Society ROPAC (Registry of Pregnancy and Cardiac Disease) registry with tissue heart valves was 1.5% and with a mechanical prosthesis was 1.4%.² Pregnancy risks for patients with heart valves include valve thrombosis, bleeding, infection, arrhythmias, and heart failure. Patients require skilled counseling and ideally are managed at expert centers with intensive monitoring.

Figure 1.

Estimated Adverse Pregnancy Rates With Prosthetic Valves From Frequently Used Stratification Schemes

mWHO criteria was originally based on expert consensus but was subsequently validated. CARPREG II included 1,938 pregnancies (1994-2014) followed from pregnancy to 6 months postpartum. The ROPAC registry studied 346 patients with prosthetic valves compared with 2,620 patients with other heart disease.1, 2, 3 CARPREG II = Cardiac Problems in Pregnancy Study II; HF = heart failure; mWHO = modified World Health Organization; ROPAC = European Society of Cardiology Registry Of Pregnancy and Cardiac Disease.

Question 2: How is maternal mortality defined?

Organizations differ on the definition of maternal mortality. The National Center for Health Statistics uses death certificate International Classification of Disease-10th Revision-Clinical Modification codes to identify maternal deaths producing a maternal mortality rate (deaths per 100,000 live births during pregnancy up to 42 days postpartum). In contrast, the Pregnancy Mortality Surveillance System assigns deaths related to pregnancy by a checkbox on the death certificate or by linked birth and fetal death certificates in the year preceding death. World Health Organization statistics often address deaths until 42 days postpartum, but also examine late maternal deaths from >42 days to 1 year.

Current Pregnancy Mortality Surveillance System data confirm that cardiovascular disease (cardiomyopathy and other forms of cardiovascular disease combined) are leading forms of maternal death.⁴

Question 3: How do maternal mortality review committees differ?

Maternal Mortality Review Committees (MMRCs) are multidisciplinary committees convened at state or local levels to comprehensively review maternal deaths occurring during pregnancy or within 1 year of pregnancy. Participants may include diverse experts in public health, obstetrics, maternal-fetal medicine, midwives, emergency medicine, social workers, pathologists, mental health, cardiologists, and nonclinical advocates such as members of community-based organizations. The state requests all known records pertinent to the death including hospital records, coroner records, police reports, and prescription history. Abstractors access this information allowing for an in-depth analysis of factors that led to the maternal death. MMRCs make recommendations to promote population-based prevention, beyond hospital and provider level, strategies and promote improved outcomes. Currently 46 states and 2 territories are funded by the Centers for Disease Control ERASE MM (Enhancing Reviews and Surveillance to Eliminate Maternal Mortality) Program.⁵ These committees use a standardized application to characterize pregnancy-related maternal deaths and identify prevention strategies called the Maternal Mortality Review Information Application (MMRIA, or “Maria”).⁶

Question 4: What key questions can MMRCs address?

What is the underlying cause of death?

This is the most important factor to determine. Valvular heart disease was the underlying etiology that ultimately led to her death although the immediate cause of death was multiorgan failure from hemorrhage, infected hematoma, and sepsis. Contributing medical factors included endocarditis, atrial arrhythmias, embolic cerebrovascular event, and morbid obesity.

Is the death pregnancy related?

A death is pregnancy related when it occurs after a pregnancy complication, a chain of events initiated by pregnancy, or if the physiological changes of pregnancy aggravated the underlying condition. In this case the death is pregnancy related resulting from complications initiated at the time of delivery.

Was the death preventable?

A death is “preventable” if the committee determines that there is at least some chance of the death being averted with reasonable changes to patient, family, provider, facility, system, and/or community factors. If the death is not preventable, then no contributing factors or recommendations are identified. A 32-state MMRC analysis of maternal cardiovascular mortality from 2017 to 2019 found that more than 75% of the deaths were preventable.⁷

What factors contributed to this death?

Contributing factors may be present at several levels including patient, provider, hospital/facility, community, and systems. Some factors based on aggregated reviews by our MMRC of preventable cardiac deaths are shown in Figure 2. For example, were appropriate referrals made to specialists? Pregnancy risk for a patient with a prosthetic valve should be addressed before pregnancy and appropriate contraceptive counseling performed. If the patient is pregnant, a referral should be made to maternal-fetal medicine if the patient elects to continue the pregnancy and for termination if the pregnancy risk is deemed too high to continue. Was cardiology consulted if the initial presentation was to obstetrics? Did provider knowledge of clinical management meet care standards? Were problematic or teratogenic medications properly adjusted when the pregnancy was initially diagnosed if this had not been done before pregnancy? Was the delivery plan addressed and documented before term? What would be indications for cesarean mode of delivery such as full anticoagulation or an obstetric indication? Was there adequate care coordination? Social determinants of health such as care access need to be considered. In this case, a multidisciplinary team could include maternal-fetal medicine, cardiology, obstetric anesthesia, and appropriate social services for the patient to access care. Was the patient advised of indications to seek postpartum care?

Figure 2.

Factors Contributing to Death Based on MMRC Review

Factors contributing to the death occurred at multiple levels including provider, hospital/facility, community, patient/family, and state/government. MFM = maternal-fetal medicine; MMRC = Maternal Mortality Review Committee.

Question 5: What recommendations and actions can address these contributing factors with impact?

Sample specific interventions that might be apropos are shown in Figure 3.

Figure 3.

Sample Interventions to Improve Outcome

Recommendations could be made at multiple levels to reduce the likelihood of maternal mortality.

Early identification of women at risk of cardiovascular decompensation during pregnancy is critical. Improved training in cardio-obstetrics and implementation of team-based care for women with cardiovascular disease from preconception, throughout pregnancy, and extending postpartum can improve provider skill, care, and quality. Collaboration between cardiac, obstetric, and maternal-fetal medicine societies can help identify screening parameters. Hospital policies can be used to promote best practices for cesarean delivery and implement hemorrhage and sepsis bundles. Reviews of case management can identify research gaps such as optimal anticoagulation strategies. MMRC review has also allowed for focus on the impact of bias, social determinants of health, and racism in maternal outcomes.

Pregnant people who live in rural or impoverished communities may not have access to cardio-obstetric specialists. Maternal cardiac care will need to expand to include new paradigms such as telehealth or implementation of ancillary services through new routes (eg, doulas). Multidisciplinary committee input may help identify novel interventions.

Many adverse pregnancy outcomes occur postpartum. A 36-state MMRC assessment of pregnancy-related deaths found 53% of pregnancy-related deaths occur >1 week postpartum and 30% occurred more than 42 days.⁸ Delayed mortality is even more common with cardiomyopathy.⁷ Before 2022 most states continued Medicaid coverage to a maximum of 42 days postpartum. Mortality review demonstrating the importance of late mortality has underscored the importance of extending Medicaid coverage to 1 year postpartum as a means to improve maternal health. Forty-six states have extended or are now extending medical care coverage. Implementation of extended coverage has been shown to improve outcomes.⁹

Improved patient awareness of warning signs is another strategy to promote patients seeking care early before serious complications occur. Currently, the Hear Her campaign advocates reducing preventable pregnancy-related deaths by raising awareness of potentially urgent maternal warning signs.¹⁰

MMRCs are essential tools in our armamentarium to reduce rising maternal cardiac mortality. Standardized maternal mortality review has led to deeper understanding of the complex processes contributing to maternal deaths and identification of missed opportunities including recognition of racial/ethnic disparities and the contributions of social disparities. Many states formally incorporate cardiology input in this review process by having a cardiologist serve as a member of the MMRC. Illinois has used cardiology input for almost 10 years. Cardiologists play a pivotal role by analyzing if cardiac complications were appropriately diagnosed and managed, informing MMRCs of best practice for cardiac therapy and monitoring, and advocating for policy changes promoting improved maternal cardiovascular care.

Perspectives

• Maternal mortality has continued to increase in the United States and cardiovascular disease remains a major reason.

• MMRCs provide comprehensive analysis of factors contributing to the maternal death identifying actionable recommendations for prevention, management, and improved outcomes.

• MMRCs improve pregnancy and postpartum cardiovascular care through multidisciplinary recommendations that promote best clinical best practice to policy makers, providers, hospitals, and health systems and for patient education.

Funding Support and Author Disclosures

Dr Briller has received funding for the National Institutes of Health–funded REBIRTH trial (of bromocriptine in peripartum cardiomyopathy) from the pass-through entity federal award to the University of Pittsburgh (1UG3HL153847-01A1) and from subaward UIC AWD00004314 (137168-1) and from National Institutes of Health/NINR–funded EASE trial for effects of Acupuncture on Symptoms of Stable Angina: a randomized controlled trial (NR02037600). Dr Briller is an unpaid consultant for the Illinois Maternal Mortality Committee (IL MMRC) and serves on the steering committee; is a site investigator of the REBIRTH trial of bromocriptine for peripartum cardiomyopathy; and has received honoraria from the American Heart Association for academic lectures and for lectures at academic cardio-obstetric lectures; she has been a paid consultant unrelated to the topic of the paper for Medtronic incorporated. Dr Kotini-Shah is also an unpaid consultant for the IL MMRC and currently serves on the American Heart Association Emergency Cardiovascular Care Committee. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.