Differences in clinical profile of African-American women with peripartum cardiomyopathy in the United States

Epidemiology of racial/ethnic disparities in severe maternal morbidity and mortality

The literature abounds with examples of racial/ethnic disparities in both obstetric outcomes and care. Disparities in maternal mortality are well documented with non-Hispanic blacks carrying the burden of the highest maternal mortality rates. Maternal deaths likely represent only the "tip of the iceberg" with respect to pregnancy complications, leading many to explore risk factors and disparities in severe maternal morbidity, a more common precursor to maternal mortality. This review article explores commonly cited indicators of severe maternal morbidity and includes a review of the epidemiological literature supporting or refuting disparities among each indicator.

Women With Heart Failure Are Disproportionately Studied as Compared With Prevalence: A Review of Published Studies from 2013

BACKGROUND

Women with heart failure (HF) have been underrepresented in research.

OBJECTIVE

The aim of this study was to determine participation of women in HF research by evaluating research studies published in 2013 in 11 peer-reviewed journals.

METHODS

Titles, abstracts, and full publications were reviewed to determine if studies met eligibility criteria and to abstract data. Data analysis was completed using means, standard deviations, quartiles, and Pearson correlation coefficients.

RESULTS

A total of 264 studies met eligibility criteria and were reviewed. Mean percentage of women was 32% across 129 studies that used original data sources and 34% across 135 studies that used existing data sources. Median percentage of women was 29% across studies using original and existing data sources.

CONCLUSIONS

Current data from studies published in 2013 support that women continue to be underrepresented in HF studies. Further research may provide insights to better understand the experiences, needs, and outcomes of women with HF.

Peripartum Cardiomyopathy

Peripartum cardiomyopathy is a potentially life-threatening pregnancy-associated disease that typically arises in the peripartum period and is marked by left ventricular dysfunction and heart failure. The disease is relatively uncommon, but its incidence is rising. Women often recover cardiac function, but long-lasting morbidity and mortality are not infrequent. Management of peripartum cardiomyopathy is largely limited to the same neurohormonal antagonists used in other forms of cardiomyopathy, and no proven disease-specific therapies exist yet. Research in the past decade has suggested that peripartum cardiomyopathy is caused by vascular dysfunction, triggered by late-gestational maternal hormones. Most recently, information has also indicated that many cases of peripartum cardiomyopathy have genetic underpinnings. We review here the known epidemiology, clinical presentation, and management of peripartum cardiomyopathy, as well as the current knowledge of the pathophysiology of the disease.

GNB3 C825T Polymorphism and Myocardial Recovery in Peripartum Cardiomyopathy: Results of the Multicenter Investigations of Pregnancy-Associated Cardiomyopathy Study

BACKGROUND

Black women are at greater risk for peripartum cardiomyopathy (PPCM). The guanine nucleotide-binding proteins β-3 subunit (GNB3) has a polymorphism C825T. The GNB3 TT genotype more prevalent in blacks is associated with poorer outcomes. We evaluated GNB3 genotype and myocardial recovery in PPCM.

METHODS AND RESULTS

A total of 97 women with PPCM were enrolled and genotyped for the GNB3 T/C polymorphism. Left ventricular ejection fraction (LVEF) was assessed by echocardiography at entry, 6 and 12 months postpartum. LVEF over time in subjects with the GNB3 TT genotype was compared with those with the C allele overall and in black and white subsets. The cohort was 30% black, age 30+6, LVEF 0.34+0.10 at entry 31+25 days postpartum. The % GNB3 genotype for TT/CT/CC=23/41/36 and differed markedly by race (blacks=52/38/10 versus whites=10/44/46, P<0.001). In subjects with the TT genotype, LVEF at entry was lower (TT=0.31+0.09; CT+CC=0.35+0.09, P=0.054) and this difference increased at 6 (TT=0.45+0.15; CT+CC=0.53+0.08, P=0.002) and 12 months (TT=0.45+0.15; CT+CC=0.56+0.07, P<0.001.). The difference in LVEF at 12 months by genotype was most pronounced in blacks (12 months LVEF for GNB3 TT=0.39+0.16; versus CT+CC=0.53+0.09, P=0.02) but evident in whites (TT=0.50++0.11; CT+CC=0.56+0.06, P=0.04).

CONCLUSIONS

The GNB3 TT genotype was associated with lower LVEF at 6 and 12 months in women with PPCM, and this was particularly evident in blacks. Racial differences in the prevalence and impact of GNB3 TT may contribute to poorer outcomes in black women with PPCM.

Characteristics and In-Hospital Outcomes of Peripartum Cardiomyopathy Diagnosed During Delivery in the United States From the Nationwide Inpatient Sample (NIS) Database

BACKGROUND

Peripartum cardiomyopathy (PPCM) is associated with advanced maternal age, African-American race, hypertensive disorders of pregnancy, and multiple-gestation pregnancies. Less is known regarding racial differences in risk factors and predictors of adverse in-hospital outcomes.

METHODS AND RESULTS

A total of 1,337 women with PPCM were identified with the use of the Nationwide Inpatient Sample (2004-2011). Clinical profiles and maternal outcomes in delivering mothers with and without PPCM were compared and stratified by race. In multivariate analysis, established risk factors for PPCM were confirmed. Anemia (odds ratio [OR] 2.0, 95% confidence interval [CI] 1.6-2.5; P < .0001), asthma (OR 2.2, 95% CI 1.5-3.2; P = .0002), smoking (OR 33.6, 95% CI 9.3-159.4; P < .0001), and thyroid disease (OR 5.9; 95% CI 1.5-21.3; P = .01) were associated with PPCM. Risk factors significant in whites, African Americans, and Hispanics were hypertension during pregnancy and anemia. Patients with PPCM had higher rates of in-hospital adverse outcomes (P < .0001), but no differences in race or comorbidities predicted adverse events.

CONCLUSIONS

Hypertensive disorders during pregnancy and anemia were associated with PPCM in whites, African Americans, and Hispanics, providing further evidence that vascular stress may play a role in the pathogenesis of PPCM. Thyroid disorders may represent a novel risk factor for PPCM.

Shared Genetic Predisposition in Peripartum and Dilated Cardiomyopathies

Background Peripartum cardiomyopathy shares some clinical features with idiopathic dilated cardiomyopathy, a disorder caused by mutations in more than 40 genes, including TTN, which encodes the sarcomere protein titin. Methods In 172 women with peripartum cardiomyopathy, we sequenced 43 genes with variants that have been associated with dilated cardiomyopathy. We compared the prevalence of different variant types (nonsense, frameshift, and splicing) in these women with the prevalence of such variants in persons with dilated cardiomyopathy and with population controls. Results We identified 26 distinct, rare truncating variants in eight genes among women with peripartum cardiomyopathy. The prevalence of truncating variants (26 in 172 [15%]) was significantly higher than that in a reference population of 60,706 persons (4.7%, P=1.3×10(-7)) but was similar to that in a cohort of patients with dilated cardiomyopathy (55 of 332 patients [17%], P=0.81). Two thirds of identified truncating variants were in TTN, as seen in 10% of the patients and in 1.4% of the reference population (P=2.7×10(-10)); almost all TTN variants were located in the titin A-band. Seven of the TTN truncating variants were previously reported in patients with idiopathic dilated cardiomyopathy. In a clinically well-characterized cohort of 83 women with peripartum cardiomyopathy, the presence of TTN truncating variants was significantly correlated with a lower ejection fraction at 1-year follow-up (P=0.005). Conclusions The distribution of truncating variants in a large series of women with peripartum cardiomyopathy was remarkably similar to that found in patients with idiopathic dilated cardiomyopathy. TTN truncating variants were the most prevalent genetic predisposition in each disorder.

Molecular mechanisms of peripartum cardiomyopathy: A vascular/hormonal hypothesis

Peripartum cardiomyopathy (PPCM) is characterized by the development of systolic heart failure in the last month of pregnancy or within the first 5 months postpartum. The disease affects between 1:300 and 1:3000 births worldwide. Heart failure can resolve spontaneously but often does not. Mortality rates, like incidence, vary widely based on location, ranging from 0% to 25%. The consequences of PPCM are thus often devastating for an otherwise healthy young woman and her newborn. The cause of PPCM remains elusive. Numerous hypotheses have been proposed, with mixed supporting evidence. Recent work has suggested that PPCM is a vascular disease, triggered by the profound hormonal changes of late gestation. We focus here on these new mechanistic findings, and their potential implication for understanding and treating PPCM.

Peripartum Cardiomyopathy: Current Knowledge and Future Directions

Peripartum cardiomyopathy is a form of heart failure occurring at the end of pregnancy or early in the postpartum period. Women may recover, have persistent cardiac dysfunction or suffer complications and death. Women who are African-American, older, hypertensive or have multiple gestation pregnancies have increased risk. Diagnosis and treatment may be delayed due to similarities between symptoms of normal pregnancy and heart failure. Echocardiography is essential for the diagnosis, and B-type natriuretic peptide can be helpful. Treatment for systolic heart failure must be adjusted during pregnancy, and anticoagulation may be indicated. Even after recovery, subsequent pregnancy confers substantial risk of worsening heart failure. Further investigations into the etiology, duration of treatment and risks for relapse are needed.

Cardiomyopathy in pregnancy

Cardiomyopathy during pregnancy is uncommon but potentially catastrophic to maternal health, accounting for up to 11% of maternal deaths. Peripartum cardiomyopathy is diagnosed in women without a history of heart disease 1 month before delivery or within 5 months postpartum. About half of all women will have full myocardial recovery within 6 months of diagnosis, but complications such as severe heart failure or death are not rare. African-American women have higher rates of diagnosis and adverse events. Women with preexisting cardiomyopathy, such as dilated or hypertrophic cardiomyopathy, followed closely during pregnancy often tolerate pregnancy and delivery. Risk factors for adverse outcomes include functional status at baseline, severity of systolic dysfunction or outflow tract gradient, or history of prior cardiac event, such as arrhythmia or stroke. The level of brain natriuretic peptide (BNP) can be used to risk stratify women for adverse events. Pregnant women with cardiomyopathy should be followed closely by a multidisciplinary team comprised of nurses, obstetricians, neonatologists, cardiologists, anesthesiologists, and cardiac surgeons.

Earlier detection can help avoid many serious complications of peripartum cardiomyopathy

Peripartum cardiomyopathy (PPCM) has a remarkable potential for recovery. It may be within our capability to help almost all women with PPCM not only to survive, but also to completely recover heart function. Time-of-diagnosis left ventricular ejection fraction (LVEF) ≥0.35 is associated with better survival rates and higher full recovery rates. Increased mortality, chronic cardiomyopathy, thromboembolic complications and serious ventricular tachyarrhythmias are associated with diagnostic LVEF <0.30. Delays in diagnosis may result in lower LVEF at diagnosis and subsequent lower recovery rates. Greater awareness of the possibility of heart failure developing in previously healthy young women, with no history of heart disease, will contribute to earlier diagnosis, with potentially better preserved heart function. Women of African descent may be at higher risk for poorer outcomes. Recent investigations suggest newer biomarkers may help with earlier detection of PPCM.

An update on treatments and outcomes in peripartum cardiomyopathy

ABSTRACT: 

Peripartum cardiomyopathy (PPCM) is a well-established complication of pregnancy. Criteria include heart failure that presents with reduced left ventricular function, signs and symptoms of heart failure either late in pregnancy or early in the postpartum period. The incidence varies widely depending geography and ethnicity. The pathophysiology of PPCM is still an area of active investigation, but includes immune and inflammatory mechanisms, which are the subject of several investigations. Therapies for chronic heart failure from PPCM are similar to those patients with nonischemic cardiomyopathy from different etiologies, however novel therapies may include bromocriptine, pentoxifylline or other potential therapies influencing the immune system. The need for implantable defibrillators, left ventricular assist devices and cardiac transplant in women with PPCM is rare, and prognosis is better than other forms of nonischemic cardiomyopathy. Despite this, further information about the epidemiology, prognosis and potential therapies are required to better manage and diagnose PPCM in women with signs and symptoms of heart failure.

Peripartum cardiomyopathy: update 2012

PURPOSE OF REVIEW

Peripartum cardiomyopathy (PPCM) is a disorder in which initial left ventricular systolic dysfunction and symptoms of heart failure occur between the late stages of pregnancy and the early postpartum period. Incidences vary geographically; it is common in some countries and rare in others. The acute form of PPCM is a clinical syndrome with reduced cardiac output, tissue hypoperfusion, and increase in the pulmonary capillary wedge pressure. Monitoring of the patient with the acute form of PPCM should be initiated as soon as possible. The syndrome carries a high morbidity and mortality and diagnosis is often delayed. This review focuses on new data and aspects in terms of diagnosis, causes of disease, pharmacological therapy, and management of delivery in patients with PPCM.

RECENT FINDINGS

New investigations reveal that PPCM is likely due to multiple factors. It develops based on oxidative stress leading to cleavage of deleterious 16-kDa prolactin, which can be blocked with bromocriptine. New data show furthermore that it is partly a two-hit vascular disease due to imbalances in angiogenic signaling worsening the severity of the disease.

SUMMARY

Different mechanisms have been investigated and give rise to promising therapeutic approach, which will be developed based on the new findings.

Peripartum cardiomyopathy: A puzzle closer to solution

Peripartum cardiomyopathy (PPCM) represents new heart failure in a previously heart-healthy peripartum patient. It is necessary to rule out all other known causes of heart failure before accepting a diagnosis of PPCM. The modern era for PPCM in the United States and beyond began with the report of the National Institutes of Health PPCM Workshop in 2000, clarifying all then-currently known aspects of the disease. Since then, hundreds of publications have appeared, an indication of how devastating this disease can be to young mothers and their families and the urgent desire to find solutions for its cause and better treatment. The purpose of this review is to highlight the important advances that have brought us nearer to the solution of this puzzle, focusing on what we have learned about PPCM since 2000; and what still remains unanswered. Despite many improvements in outcome, we still do not know the actual triggers that initiate the pathological process; but realize that cardiac angiogenic imbalances resulting from complex pregnancy-related immune system and hormonal changes play a key role.

The relationship between pre-eclampsia and peripartum cardiomyopathy: a systematic review and meta-analysis

OBJECTIVES

The goal of this study was to systematically review the peripartum cardiomyopathy (PPCM) literature and determine the prevalence of pre-eclampsia (PE) in women with PPCM. Secondary analyses included evaluation of the prevalence of hypertensive disorders, multiple gestations, and multiparity.

BACKGROUND

PPCM is a significant cause of maternal and infant morbidity and mortality worldwide, yet its etiology remains unknown. PE is often cited as a risk factor for the development of PPCM and recent research suggests that PE and PPCM share mechanisms that contribute to their pathobiology. No comprehensive evaluation of the relationship between PE and PPCM exists.

METHODS

A systematic predetermined search strategy was performed in multiple databases to identify studies describing ≥3 women with PPCM. Prevalence rates of PE, hypertension, multiple gestations, and multiparity were pooled.

RESULTS

Data from 22 studies (n = 979) were included in this analysis. The pooled prevalence of 22% (95% confidence interval [CI]: 16% to 28%) was more than quadruple the 5% average worldwide background rate of PE in pregnancy (p < 0.001). There were no geographic or racial differences detected in the prevalence of PE in women with PPCM. The rates of hypertension during pregnancy (37% [95% CI: 29% to 45%]) and multiple gestations (9% [95% CI: 7% to 11%]) were also elevated.

CONCLUSIONS

The prevalence of PE, hypertensive disorders, and multiple gestations in women with PPCM is markedly higher than that in the general population. These findings support the concept of a shared pathogenesis between PE and PPCM and highlight the need for awareness of the overlap between these 2 diseases.