What are the recommendations for using spironolactone (aldosterone antagonist) in breastfeeding mothers with peripartum cardiomyopathy according to European Society of Cardiology (ESC) 2025 guidelines?

Spironolactone Use in Breastfeeding Mothers with Peripartum Cardiomyopathy

Spironolactone should be avoided in breastfeeding mothers with peripartum cardiomyopathy according to European Society of Cardiology guidelines. 1

Rationale for Avoiding Spironolactone

The ESC guidelines clearly state that aldosterone antagonists, including spironolactone, should be avoided in breastfeeding women with peripartum cardiomyopathy for several important reasons:

1. Potential antiandrogenic effects: Spironolactone has been associated with antiandrogenic effects, particularly concerning in the first trimester of pregnancy 1

2. Reduction in milk production: Diuretics including spironolactone may reduce milk production, which is generally undesirable in breastfeeding women 1

3. Limited safety data: There is insufficient data regarding the safety of eplerenone (another aldosterone antagonist) in breastfeeding 1

Recommended Heart Failure Management During Breastfeeding

For breastfeeding mothers with PPCM requiring heart failure treatment, the guidelines recommend:

Preferred Medications

• ACE inhibitors: Specific ACE inhibitors that have been adequately tested in breastfeeding women include:
  • Benazepril
  • Captopril
  • Enalapril 1

These ACE inhibitors are considered safe for the baby, though monitoring the infant's weight during the first 4 weeks is essential as an indicator of potential kidney dysfunction 1.

Other Heart Failure Medications During Breastfeeding

• Beta-blockers: Beta-1 selective agents (e.g., metoprolol) are preferred if tolerated 1
• Diuretics: If needed for pulmonary congestion, furosemide and hydrochlorothiazide are most frequently used 1
• Anticoagulation: Should be considered in patients with very low ejection fraction due to increased risk of peripheral and cerebral embolism in PPCM patients 1

Considerations Regarding Breastfeeding in PPCM

It's important to note that some guidelines suggest that breastfeeding itself may be discouraged in PPCM patients due to:

1. High metabolic demands of lactation 1, 2
2. Postulated negative effects of prolactin subfragments 1
3. Potential benefits of bromocriptine (which stops lactation) in addition to standard heart failure therapy for PPCM patients 1, 2

Monitoring and Follow-up

For women with PPCM who are breastfeeding:

• Monitor infant weight during the first 4 weeks when using ACE inhibitors 1
• Close cardiac monitoring of the mother is essential as deterioration in LV function is reported in up to 50% of cases despite optimal medical treatment 1
• Mortality rates vary geographically from 0-9% in white populations in the USA to up to 15% in other populations 1

Key Takeaways

• Avoid spironolactone in breastfeeding mothers with PPCM
• Use ACE inhibitors like benazepril, captopril, or enalapril if heart failure treatment is needed
• Consider the risks and benefits of breastfeeding itself in PPCM patients
• Monitor both mother and infant closely during treatment

The management of PPCM requires careful consideration of both maternal cardiac health and infant safety, with treatment decisions guided by the goal of improving maternal morbidity and mortality while minimizing risks to the breastfeeding infant.