NT-proBNP and predictors of event free survival and left ventricular systolic function recovery in peripartum cardiomyopathy

The association of heart rate with adverse outcomes and recurrent heart failure hospitalization in peripartum cardiomyopathy

INTRODUCTION

Understanding predictors of adverse outcomes in patients with peripartum cardiomyopathy (PPCM) is essential for risk stratification and prognosis. The aim of this study is to examine the relationship between heart rate (HR) at diagnosis and adverse outcomes in PPCM.

METHODS

We conducted a multi-center cohort study to identify patients with PPCM (1993-2017) who met the inclusion criteria: left ventricular ejection fraction (LVEF) <40%, development of heart failure within the last month of pregnancy or within 5 months of delivery, and no other identifiable cause of heart failure with reduced ejection fraction. The primary composite outcome of major adverse events included recurrent heart failure hospitalization, need for extra-corporeal membrane oxygenation, left ventricular assist device, orthotopic heart transplant, or all-cause death. Using Cox proportional hazards models, we examined the relationship between categories of HR at diagnosis and adverse outcomes.

RESULTS

A total of 177 women met criteria (81 with HR <100 bpm, 54 with HR 100-119 bpm, 42 with HR ≥120 bpm) with a mean age of 32 ± 7 years and median follow-up 3.6 years (IQR 1.1-8.2); 48 (27%) experienced the composite outcome. In a multivariable model adjusting for age, race, preeclampsia and hypertension, women with HR ≥ 120 bpm were four times more likely to experience major adverse events compared to women with HR < 100 bpm (HR 4.1, 95% CI 1.6-10.4) at the time of diagnosis. In a second multivariable model adjusting for the above covariates plus LVEF < 30%, QTc, and systolic blood pressure, those with HR ≥ 120 bpm were more likely to experience major adverse events compared to those with HR < 100 bpm (HR 3.31 (1.01-10.9), p = 0.049). Patients with HR <100 bpm were significantly more likely to have survival free from adverse events in survival analysis (p = 0.03).

CONCLUSION

Sinus tachycardia at diagnosis was associated with lower LVEF on presentation and higher rates of major adverse events in PPCM. Tachycardia may be an early prognostic indicator of outcomes in PPCM and could help identify high-risk patients for closer follow-up and earlier intervention.

Diagnosis and management of peripartum cardiomyopathy and recurrence risk

Peripartum cardiomyopathy (PPCM) is a rare, but serious condition, with a non-negligible risk of adverse events. Several risk factors for PPCM have been individuated over the years, including Afro-American ethnicity, preeclampsia, advanced maternal age, genetic predisposition, multiparity, twin pregnancy, obesity, smoking and diabetes. However, PPCM pathophysiology is still poorly understood, thus making it challenging to develop disease specific therapies. At present, Bromocriptine is the only targeted drug, but further evidence is needed to establish indication and timing of administration. Therefore, these patients are mainly treated following general heart failure guidelines. Even though in most patients left ventricular ejection fraction recovers during follow-up, cases of persistent left ventricular dysfunction are not uncommon. Moreover, all patients detain a certain risk of recurrence after subsequent pregnancies, which is difficult to estimate due to the dearth of long-term prospective data. In this manuscript, we aim to provide an updated review of current evidence about PPCM pathophysiology, diagnosis, treatment and recurrence risk. In addition, we discuss the gaps in knowledge that should be addressed by future research.

Clinical predictors of right ventricular dysfunction and association with adverse outcomes in peripartum cardiomyopathy

AIMS

We sought to identify factors associated with right ventricular (RV) dysfunction and elevated pulmonary artery systolic pressure (PASP) and association with adverse outcomes in peripartum cardiomyopathy (PPCM).

METHODS AND RESULTS

We conducted a multi-centre cohort study to identify subjects with PPCM with the following criteria: left ventricular ejection fraction (LVEF) < 40%, development of heart failure within the last month of pregnancy or 5 months of delivery, and no other identifiable cause of heart failure with reduced ejection fraction. Outcomes included a composite of (i) major adverse events (need for extracorporeal membrane oxygenation, ventricular assist device, orthotopic heart transplantation, or death) or (ii) recurrent heart failure hospitalization. RV function was obtained from echocardiogram reports. In total, 229 women (1993-2017) met criteria for PPCM. Mean age was 32.4 ± 6.8 years, 28% were of African descent, 50 (22%) had RV dysfunction, and 38 (17%) had PASP ≥ 30 mmHg. After a median follow-up of 3.4 years (interquartile range 1.0-8.8), 58 (25%) experienced the composite outcome of adverse events. African descent, family history of cardiomyopathy, LVEF, and PASP were significant predictors of RV dysfunction. Using Cox proportional hazards models, we found that women with RV dysfunction were three times more likely to experience the adverse composite outcome: hazard ratio 3.21 (95% confidence interval: 1.11-9.28), P = 0.03, in a multivariable model adjusting for age, race, body mass index, preeclampsia, hypertension, diabetes, kidney disease, and LVEF. Women with PASP ≥ 30 mmHg had a lower probability of survival free from adverse events (log-rank P = 0.04).

CONCLUSIONS

African descent and family history of cardiomyopathy were significant predictors of RV dysfunction. RV dysfunction and elevated PASP were significantly associated with a composite of major adverse cardiac events. This at-risk group may prompt closer monitoring or early referral for advanced therapies.

Biomarkers in Peripartum Cardiomyopathy-What We Know and What Is Still to Be Found

Peripartum cardiomyopathy (PPCM) is a form of heart failure, often severe, that occurs in previously healthy women at the end of their pregnancy or in the first few months after delivery. In PPCM, the recovery of heart function reaches 45-50%. However, the all-cause mortality in long-term observation remains high, reaching 20% irrespective of recovery status. The incidence of PPCM is increasing globally; therefore, effort is required to clarify the pathophysiological background of the disease, as well as to discover specific diagnostic and prognostic biomarkers. The etiology of the disease remains unclear, including oxidative stress; inflammation; hormonal disturbances; endothelial, microcirculatory, cardiomyocyte and extracellular matrix dysfunction; fibrosis; and genetic mutations. Currently, antiangiogenic 16-kDa prolactin (PRL), cleaved from standard 23-kDa PRL in the case of unbalanced oxidative stress, is recognized as the main trigger of the disease. In addition, 16-kDa PRL causes damage to cardiomyocytes, acting via microRNA-146a secreted from endothelial cells as a cause of the NF-κβ pathway. Bromocriptine, which inhibits the secretion of PRL from the pituitary gland, is now the only specific treatment for PPCM. Many different phenotypes of the disease, as well as cases of non-responders to bromocriptine treatment, indicate other pathophysiological pathways that need further investigation. Biomarkers in PPCM are not well established. There is a deficiency in specific diagnostic biomarkers. Pro-brain-type natriuretic peptide (BNP) and N-terminal BNP are the best, however unspecific, diagnostic biomarkers of heart failure at the moment. Therefore, more efforts should be engaged in investigating more specific biomolecules of a diagnostic and prognostic manner such as 16-kDa PRL, galectin-3, myeloperoxidase, or soluble Fms-like tyrosine kinase-1/placental growth factor ratio. In this review, we present the current state of knowledge and future directions of exploring PPCM pathophysiology, including microRNA and heat shock proteins, which may improve diagnosis, treatment monitoring, and the development of specific treatment strategies, and consequently improve patients' prognosis and outcome.

The Utilization and Interpretation of Cardiac Biomarkers During Pregnancy: JACC: Advances Expert Panel

Cardiac biomarkers are widely used in the nonpregnant population when acute cardiovascular (CV) pathology is suspected; however, the behavior of these biomarkers in the context of pregnancy is less well understood. Pregnant individuals often have symptoms that mimic those of cardiac dysfunction, and complications of pregnancy may include CV disease. This paper will summarize our current knowledge on the use of cardiac biomarkers in pregnancy and provide suggestions on how to use these tools in clinical practice based on the available evidence. Natriuretic peptides and troponin should not be measured routinely in uncomplicated pregnancy, where values should remain low as in the nonpregnant population. In the context of pre-existing or suspected CV disease, these biomarkers retain their negative predictive value. Elevations of both natriuretic peptides and troponin may occur without clear clinical significance in the immediate postpartum period. Elevations of these markers should always prompt further investigation into possible CV pathology.