Postpartum Cardiomyopathy Diagnosis and Treatment

Postpartum cardiomyopathy is not a common diagnosis but one that requires timely diagnosis and treatment as it can cause severe complications for mother and child. The Heart Failure Association and European Society of Cardiology Study Group define postpartum cardiomyopathy as “idiopathic cardiomyopathy occurring towards the end of pregnancy or in the months following delivery, abortion, or miscarriage without other causes of heart failure and an ejection fraction less than 45%.”¹ This disease process is diagnosed by exclusion because of the lack of specific diagnostic testing.

Etiology and Pathology

The etiology behind postpartum cardiomyopathy is unknown. Research suggests an increased risk in patients of African descent, with an estimated incidence of 1:100 pregnancies in Nigeria and 1:299 pregnancies in Haiti.¹ The incidence among White patients differs by geographic region with rates of 1:1500 pregnancies in Germany compared with 1:10,000 pregnancies in Denmark. Other contributing factors include multiple pregnancies, family history, smoking, diabetes, hypertension, pre-eclampsia, malnutrition, maternal age, and prolonged use of tocolytic beta-agonists.¹

In addition to being at higher risk for postpartum cardiomyopathy, Black women are diagnosed with the condition at a younger age and with left ventricular ejection fraction (LVEF) less than 30% compared with non-Black women.¹ Research suggests that Black individuals present with more severe disease, have a longer recovery time, and recover less frequently even with appropriate treatments than their counterparts.² Additional genome research is needed to understand these differences.²  

Genetic testing for postpartum cardiomyopathy may be considered, particularly in patients with a family history of the condition.¹ In a cohort of Danish patients, women with postpartum cardiomyopathy were more likely to have a family history of heart failure in any first-degree relative than among those without postpartum cardiomyopathy (23% vs 10%; P =.011).³ Although more research is needed, genetic mutations appear to contribute to up to 20% of postpartum cardiomyopathy cases.¹

Clinical Presentation

Clinical presentation of postpartum cardiomyopathy is similar to that of heart failure: shortness of breath, cough, palpitations, fatigue, peripheral edema, chest pain, dizziness, and orthopnea.¹ Most of these symptoms can be correlated with fluid shifts in pregnancies; thus, it is essential to monitor mothers during the postpartum period to ensure a prompt return to the prepregnancy state.¹

Diagnosis of Postpartum Cardiomyopathy

The diagnosis should consider the patient’s medical history and timing of symptom onset as postpartum cardiomyopathy symptoms typically begin 1-month predelivery to up to 5 months postdelivery. The review of systems should look for cough, shortness of breath, and chest pain. Physical examination should include heart and lung sounds and extremity edema.

Laboratory evaluations should include brain-type natriuretic peptide (BNP) with values greater than 100 pg/mL indicative of postpartum cardiomyopathy. Although an elevated BNP may occur in healthy pregnancies, levels will not be as high as those in patients with heart failure.⁴ N-terminal proBNP-type natriuretic peptide level greater than 300 pg/mL indicates heart failure.¹ Baseline complete blood cell count (CBC), renal, and lipid panels should be ordered to help with diagnosis. Other tests include echocardiography with an ejection fracture of less than 40% indicating heart failure.⁵ Chest radiography to examine the cardiac silhouette for more severe cases may be indicated but the clinician should weigh the risk vs benefits of radiation exposure to the fetus.

Treatment and Follow-up

The severity of postpartum cardiomyopathy and whether the woman is pregnant or breastfeeding determines the treatment plan. Timely diagnosis and proper planning are crucial for restoring cardiac function and preventing more damage. It is essential to use a multidisciplinary team approach for this treatment including a cardiologist, intensivist, obstetrician, neonatologist, and cardiac surgeon.⁵

Table. Treatment Strategies for Postpartum Cardiomyopathy¹

Severity Level	Clinical Presentation/Echocardiography	Treatment
Mild PPCM	• Subacute heart failure and hemodynamic stability • LVEF 30%-45%	• Treat with oral heart failure drugs, oral diuretics in cases with fluid overload, and potentially bromocriptine for 1 week
Moderate PCCM	• Acute heart failure, hemodynamic stability, and respiratory insufficiency • LVEF 20%-35%	• Requires hospitalization for IV diuretics • Vasorelaxant and supplemental oxygen may be warranted • If LVEF <25%, consider bromocriptine for 8 weeks and oral heart failure drugs
Severe PCCM	• Cardiogenic shock, hemodynamic instability, respiratory insufficiency • LVEF <25%	• Requires ICU hospitalization along with IV diuretics, inotropes/catecholamines (if necessary), invasive ventilation, and mechanical circulatory support • 8 weeks of bromocriptine may be considered based on prolactin levels • Once stabilized, the patient should be given oral heart failure medications

Follow-up is recommended at 1-year postdiagnosis; future pregnancies should be discussed with the patient and the multidisciplinary team. The research shows an increased risk for cardiomyopathy to present in other pregnancies and should be discouraged against future pregnancies. The risk for relapse and death is high for women with impaired systolic function.¹

Conclusion

The take-home points for management of patients with postpartum cardiomyopathy are to diagnose and treat the condition promptly. Remember the specific criteria for diagnosis: no prior cardiac history, within the last month of pregnancy and up to 5 months postpartum, LVEF less than 45%, and no identifiable cause of the heart failure. The treatment plan differs with the status of pregnancy and breastfeeding. Each case should be considered and tailored to the patient and situation. Patient counseling on future children should be discussed, and the risks of recurring cardiac failure should be elevated.

Mallory Winnicki, BSN, RN, is a surgical ICU nurse and she has witnessed an increase in mothers admitted with postpartum cardiomyopathy. She is currently enrolled in a Doctoral Family Nurse Practitioner program.

References

1. Bauersachs J, König T, van der Meer P, et al. Pathophysiology, diagnosis and management of peripartum cardiomyopathy: a position statement from the Heart Failure Association of the European Society of Cardiology Study Group on peripartum cardiomyopathy. Eur J Heart Fail. 2019;21(7):827-843. doi:10.1002/ejhf.1493
2. Irizarry OC, Levine LD, Lewey J, et al. Comparison of clinical characteristics and outcomes of peripartum cardiomyopathy between African American and non-African American women. JAMA Cardiol. 2017;2(11):1256-1260. doi:10.1001/jamacardio.2017.3574
3. Christiansen MN, Køber L, Torp-Pedersen C, et al. Prevalence of heart failure and other risk factors among first-degree relatives of women with peripartum cardiomyopathy. Heart. 2019;105(14):1057-1062. doi:10.1136/heartjnl-2018-314552
4. Tanous D, Siu SC, Mason J, et al. B-type natriuretic peptide in pregnant women with heart disease. J Am Coll Cardiol. 2010;56(15):1247-1253. doi:10.1016/j.jacc.2010.02.076
5. Heidenreich PA, Bozkurt B, Aguilar D, et al. 2022 AHA/ACC/HFSA guideline for the management of heart failure: a report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. J Am Coll Cardiol. 2022;79(17):e263-e421. doi:10.1016/j.jacc.2021.12.012