Biomarkers and Their Relation to Cardiac Function Late After Peripartum Cardiomyopathy

Peripartum cardiomyopathy: a comprehensive and contemporary review

Cardiovascular disease is a major non-communicable disease globally, with increasing prevalence, posing a significant public health challenge. It is the leading non-obstetric cause of perinatal morbidity and mortality, with a substantial number of cardiac fatalities occurring in individuals without any known pre-existing cardiovascular disease. Peripartum cardiomyopathy is a type of de novo heart failure that occurs in pregnant women in the late stages of pregnancy or following delivery. Despite extensive research, diagnosing and managing peripartum cardiomyopathy remains challenging, resulting in significant morbidity and mortality. Recent advancements and novel approaches have been made to better understand and manage peripartum cardiomyopathy, including molecular and non-molecular biomarkers, genetic predisposition and risk prediction, targeted therapies, multidisciplinary care, and improved patient education. This narrative review provides a comprehensive overview and new perspectives on peripartum cardiomyopathy, covering its epidemiology, updated pathophysiological mechanisms, diagnosis, management, and future research directions for healthcare professionals, researchers, and clinicians.

Sex-based Differences in Heart Failure Biomarkers

PURPOSE OF REVIEW

Differences in HF biomarker levels by sex may be due to hormonal, genetic, and fat distribution differences. Knowledge of these differences is scarce, and it is not well established whether they may affect their usefulness in the management of HF.

RECENT FINDINGS

The different biomarker profiles in women and men have been confirmed in recent studies: in women, markers of cardiac stretch and fibrosis (NP and galectin-3) are higher, whereas in men, higher levels of markers of cardiac injury and inflammation (cTn and sST2) are found. The use of new biomarkers, together with growing evidence that a multimarker approach can provide better risk stratification, raises the question of building models that incorporate sex-specific diagnostic criteria. More and more research are being devoted to understanding sex-related differences in HF. The aim of this review is to review the dynamics of HF biomarkers according to sex and in different situations, to learn whether these sex differences may affect their use in the diagnosis and follow-up of HF patients.

Connecting the Dots: Exploring the Interplay Between Preeclampsia and Peripartum Cardiomyopathy

Preeclampsia and peripartum cardiomyopathy (PPCM) are significant obstetric problems that can arise during or after pregnancy. Both are known to be causes of maternal mortality and morbidity. Several recent studies have suggested a link between preeclampsia and the pathophysiology of PPCM. However, the common thread that connects the two has yet to be thoroughly and fully articulated. Here, we investigate the complex dynamics of preeclampsia and PPCM in this review. Our analysis focuses mainly on inflammatory and immunological responses, endothelial dysfunction as a shared pathway, and potential genetic predisposition to both diseases. To begin, we will look at how excessive inflammatory and immunological responses can lead to clinical symptoms of both illnesses, emphasizing the role of proinflammatory cytokines and immune cells in modifying vascular and tissue responses. Second, we consider endothelial dysfunction to be a crucial point at which endothelial damage and activation contribute to pathogenesis through increased vascular permeability, vascular dysfunction, and thrombus formation. Finally, we examine recent information suggesting genetic predispositions to preeclampsia and PPCM, such as genetic variants in genes involved in the management of blood pressure, the inflammatory response, and heart structural integrity. With this synergistic study, we seek to encourage more research and creative therapy solutions by emphasizing the need for an interdisciplinary approach to understanding and managing the connection between preeclampsia and PPCM.

Vascular endothelial growth factors and risk of cardio-renal events: Results from the CREDENCE trial

BACKGROUND

Circulating concentrations of vascular endothelial growth factor (VEGF) family members may be abnormally elevated in type 2 diabetes (T2D). The roles of placental growth factor (PlGF), soluble fms-like tyrosine kinase-1 (sFLT-1), and VEGF-A in cardio-renal complications of T2D are not established.

METHOD

The 2602 individuals with diabetic kidney disease (DKD) from the Canagliflozin and Renal Events in Diabetes with Established Nephropathy Clinical Evaluation trial were randomized to receive canagliflozin or placebo and followed for incident cardio-renal outcomes. PlGF, sFLT-1, and VEGF-A were measured at baseline, year 1, and year 3. Primary outcome was a composite of end-stage kidney disease, doubling of the serum creatinine, or renal/cardiovascular death. Cox proportional hazard regression was used to investigate the association between biomarkers with adverse clinical events.

RESULTS

At baseline, individuals with higher PlGF levels had more prevalent cardiovascular disease compared to those with lower values. Treatment with canagliflozin did not meaningfully change PlGF, sFLT-1, and VEGF-A concentrations at years 1 and 3. In a multivariable model, 1 unit increases in baseline log PlGF (hazard ratio [HR]: 1.76, 95% confidence interval [CI]: 1.23, 2.54, P-value = .002), sFLT-1 (HR: 3.34, [95% CI: 1.71, 6.52], P-value < .001), and PlGF/sFLT-1 ratio (HR: 4.83, [95% CI: 0.86, 27.01], P-value = .07) were associated with primary composite outcome, while 1 unit increase in log VEGF-A did not increase the risk of primary outcome (HR: 0.96 [95% CI: 0.81, 1.07]). Change by 1 year of each biomarker was also assessed: HR (95% CI) of primary composite outcome was 2.45 (1.70, 3.54) for 1 unit increase in 1-year concentration of log PlGF, 4.19 (2.18, 8.03) for 1 unit increase in 1-year concentration of log sFLT-1, and 21.08 (3.79, 117.4) for 1 unit increase in 1-year concentration of log PlGF/sFLT-1. Increase in 1-year concentrations of log VEGF-A was not associated with primary composite outcome (HR: 1.08, [95% CI: 0.93, 1.24], P-value = .30).

CONCLUSIONS

People with T2D and DKD with elevated levels of PlGF, sFLT-1, and PlGF/sFLT-1 ratio were at a higher risk for cardiorenal events. Canagliflozin did not meaningfully decrease concentrations of PlGF, sFLT-1, and VEGF-A.

CLINICAL TRIAL

CREDENCE, https://clinicaltrials.gov/ct2/show/NCT02065791.

Are fetal microchimerism and circulating fetal extracellular vesicles important links between spontaneous preterm delivery and maternal cardiovascular disease risk?

Trafficking and persistence of fetal microchimeric cells (fMCs) and circulating extracellular vesicles (EVs) have been observed in animals and humans, but their consequences in the maternal body and their mechanistic contributions to maternal physiology and pathophysiology are not yet fully defined. Fetal cells and EVs may help remodel maternal organs after pregnancy-associated changes, but the cell types and EV cargos reaching the mother in preterm pregnancies after exposure to various risk factors can be distinct from term pregnancies. As preterm delivery-associated maternal complications are rising, revisiting this topic and formulating scientific questions for future research to reduce the risk of maternal morbidities are timely. Epidemiological studies report maternal cardiovascular risk as one of the major complications after preterm delivery. This paper suggests a potential link between fMCs and circulating EVs and adverse maternal cardiovascular outcomes post-pregnancies, the underlying mechanisms, consequences, and methods for and how this link might be assessed.

Sex Differences in Circulating Biomarkers of Heart Failure

PURPOSE OF REVSIEW

Evidence is scaling up for sex differences in heart failure; however, clinical relevance of sex-specific differential thresholds for biomarkers is not clearly known. Current ambiguity warrants a further look into the sex-specific studies on cardiac biomarkers and may facilitate understanding of phenotypic presentations, clinical manifestations, and pathophysiologic pathway differences in men and women.

RECENT FINDINGS

Recent studies have confirmed the fact that females have differential threshold for biomarkers, with lower troponin and higher NT proBNP levels. Ambiguity continues to exist in the clinical relevance of ST-2, Galectin 3, and other biomarkers. Novel biomarkers, proteomic biomarkers, and circulating micro RNAs with machine learning are actively being explored. Biomarkers in HFpEF patients with higher female representation are evolving. In recent clinical trials, sex-related difference in biomarkers is not seen despite therapeutic intervention being more effective in females compared to males. Sex-related difference exists in the expression of biomarkers in health and in various disease states of heart failure. However, this differentiation has not effectively translated into the clinical practice in terms of diagnostic studies or prognostication. Active exploration to bridge the knowledge gap and novel technologies can shed more light in this area.

Association of activin A and postpartum blood pressure in peripartum cardiomyopathy

BACKGROUND

Activin A has been implicated in the pathogenesis of patients with chronic hypertension and heart failure as well as patients with hypertensive disorders of pregnancy (HDP). Whether activin A correlates with blood pressure in patients with peripartum cardiomyopathy (PPCM) and HDP history has not previously been explored.

METHODS AND RESULTS

82 women with PPCM w/ and w/out HDP or hypertension history were selected for analysis from the Investigations in Pregnancy Associated Cardiomyopathy (IPAC) study. Serum biomarkers and blood pressure were assessed at the time of enrollment (median postpartum day 24). Levels of both sFlt-1 (SBP: r 0.47, p = 0.008; DBP: r 0.57, p < 0.001) and activin A (SBP: r 0.59, p < 0.001;DBP: r 0.68, p < 0.001) were noted to significantly correlate with blood pressure in patients with a history of HDP who went on to develop PPCM, but not in patients with chronic hypertension or no hypertensive history. The strongest correlation was between activin A levels and postpartum diastolic blood pressure for the subset with preeclampsia (DBP: r0.82, p < 0.001). This remained significant in multivariable linear regression analysis (DBP: β = 0.011, p = 0.015).

CONCLUSION

In patients with PPCM, activin A and sFlt-1 levels had direct correlations with both systolic (SBP) and diastolic blood pressures (DBP), but only in participants with history of HDP. This correlation was more evident for activin A and strongest with a history of preeclampsia. Our findings suggest that activin A may play an important role in blood pressure modulation in women with HDP who subsequently develop PPCM.

Analysis of Clinical Profiles and Echocardiographic Cardiac Outcomes in Peripartum Cardiomyopathy (PPCM) vs. PPCM with Co-Existing Hypertensive Pregnancy Disorder (HPD-PPCM) Patients: A Systematic Review and Meta-Analysis

Peripartum cardiomyopathy (PPCM) is a form of new-onset heart failure that has a high rate of maternal morbidity and mortality. This was the first study to systematically investigate and compare clinical factors and echocardiographic findings between women with PPCM and co-incident hypertensive pregnancy disorders (HPD-PPCM) and PPCM-only women. We followed the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) framework. We used four databases and a single search engine, namely PubMed/Medline, Scopus, Web of Science, and Cochrane. We used Cochrane Risk of Bias (RoB) 2.0 for quality assessment. Databases were searched for relevant articles published from 2013 to the end of April 2023. The meta-analysis used the DerSimonian-Laird random-effects model to analyze the pooled mean difference (MD) and its p-value. We included four studies with a total of 64,649 participants and found that systolic blood pressure was significantly more likely to be associated with the PPCM group than the HPD-PPCM group (SMD = -1.63) (95% CI; -4.92,0.28, p = 0.01), while the other clinical profiles were not significant. HPD-PPCM was less likely to be associated with LVEF reduction (SMD = -1.55, [CI: -2.89, -0.21], p = 0.02). HPD-PPCM was significantly associated with less LV dilation (SMD = 1.81; 95% (CI 0.07-3.01), p = 0.04). Moreover, HPD-PPCM was less likely to be associated with relative wall thickness reduction (SMD = 0.70; 95% CI (-1.08--0.33), p = 0.0003). In conclusion, PPCM and HPD-PPCM shared different clinical profiles and remodeling types, which may affect each disease's response to pharmacological treatment. Patients with HPD-PPCM exhibited less eccentric remodeling and seemed to have a higher chance of recovering their LV ejection fraction, which means they might not benefit as much from ACEi/ARB and beta-blockers. The findings of this study will guide the development of guidelines for women with PPCM and HPD-PPCM from early detection to further management.

Meta-Analysis of Long-Term (>1 Year) Cardiac Outcomes of Peripartum Cardiomyopathy

Peripartum cardiomyopathy is the development of heart failure toward the end of pregnancy or in the months after delivery in the absence of other attributable causes, with left ventricular systolic dysfunction and a left ventricular ejection fraction (LVEF) generally <45%. Given that patients are relatively young at the time of diagnosis, this study was performed to summarize current evidence surrounding the long-term cardiac outcomes. MEDLINE, Embase, Cochrane CENTRAL, and CINAHL were searched for original studies that reported long-term (>1 year) patient outcomes. Of the 3,144 total records identified, 62 studies involving 4,282 patients met the selection criteria. The mean LVEF was 28% at diagnosis and 47% at the time of the last follow-up. Approximately half of the patients achieved myocardial recovery (47%), most commonly defined as an LVEF >50% (n = 21). The prevalence of implantable cardioverter-defibrillator use, left ventricular assist device implantation, and heart transplantation was 12%, 7%, and 11%, respectively. The overall all-cause mortality was 9%, and despite having more cardiovascular risk factors, patients residing in high-income countries had superior outcomes, including reduced rates of mortality.

A patient with untreated preeclampsia and peripartum cardiomyopathy

ABSTRACT

The pathophysiologic process of peripartum cardiomyopathy, a rare and potentially life-threatening condition, is not completely understood. One theory is a possible link between the development of preeclampsia and peripartum cardiomyopathy. These two conditions have been linked to significant mortality in peripartum or postpartum patients. Clinicians must be able to identify the two, their differences, and start appropriate therapies immediately.

Noninvasive Cardiac Imaging in Formerly Preeclamptic Women for Early Detection of Subclinical Myocardial Abnormalities: A 2022 Update

Preeclampsia is a maternal hypertensive disease, complicating 2–8% of all pregnancies. It has been linked to a 2–7-fold increased risk for the development of cardiovascular disease, including heart failure, later in life. A total of 40% of formerly preeclamptic women develop preclinical heart failure, which may further deteriorate into clinical heart failure. Noninvasive cardiac imaging could assist in the early detection of myocardial abnormalities, especially in the preclinical stage, when these changes are likely to be reversible. Moreover, imaging studies can improve our insights into the relationship between preeclampsia and heart failure and can be used for monitoring. Cardiac ultrasound is used to assess quantitative changes, including the left ventricular cavity volume and wall thickness, myocardial mass, systolic and diastolic function, and strain. Cardiac magnetic resonance imaging may be of additional diagnostic value to assess diffuse and focal fibrosis and perfusion. After preeclampsia, sustained elevated myocardial mass along with reduced myocardial circumferential and longitudinal strain and decreased diastolic function is reported. These findings are consistent with the early phases of heart failure, referred to as preclinical (asymptomatic) or B-stage heart failure. In this review, we will provide an up-to-date overview of the potential of cardiac magnetic resonance imaging and echocardiography in identifying formerly preeclamptic women who are at high risk for developing heart failure. The potential contribution to early cardiac screening of women with a history of preeclampsia and the pros and cons of these imaging modalities are outlined. Finally, recommendations for future research are presented.

Peripartum cardiomyopathy: a global effort to find the cause and cure for the rare and little understood disease

In this review, we present our current understanding of peripartum cardiomyopathy (PPCM) based on reports of the incidence, diagnosis and current treatment options. We summarise opinions on whether PPCM is triggered by vascular and/or hormonal causes and examine the influence of comorbidities such as preeclampsia. Two articles published in 2021 strongly support the hypothesis that PPCM may be a familial disease. Using large cohorts of PPCM patients, they summarised the available genomic DNA sequence data that are expressed in human cardiomyocytes. While PPCM is considered a disease predominately affecting the left ventricle, there are data to suggest that some cases also involve right ventricular failure. Finally, we conclude that there is sufficient evidence to warrant an RNAseq investigation and that this would be most informative if performed at the cardiomyocytes level rather than analysing genomic DNA from the peripheral circulation. Given the rarity of PPCM, the combined resources of international human heart tissue biobanks have assembled 30 ventricular tissue samples from PPCM patients, and we are actively seeking to enlarge this patient base by collaborating with human heart tissue banks and research laboratories who would like to join this endeavour.