How is peripartum cardiomyopathy diagnosed and managed in a woman who develops new‑onset heart‑failure symptoms during the last month of pregnancy through five months postpartum?

Diagnosis of Peripartum Cardiomyopathy

Peripartum cardiomyopathy (PPCM) is diagnosed when a woman develops heart failure with left ventricular ejection fraction below 45% during the last month of pregnancy through five months postpartum, after excluding all other causes of cardiac dysfunction. 1, 2

Diagnostic Criteria

PPCM requires meeting all of the following criteria:

• Timing: Onset of heart failure symptoms in the last month of pregnancy or within 5 months postpartum (though 78% present within the first 4 months postpartum, with peak incidence at 2-62 days after delivery) 3, 1
• Left ventricular systolic dysfunction: LVEF < 45% on echocardiography (present in virtually all cases) 2, 4
• Absence of other identifiable causes: No pre-existing heart disease before the last month of pregnancy, and exclusion of other cardiac pathology 3, 5
• No alternative explanation: Rule out myocardial infarction, pulmonary embolism, pre-eclampsia with pulmonary edema, hypertensive heart disease, and valvular disease 1, 6

Clinical Presentation

Recognize that early symptoms mimic normal pregnancy, requiring high clinical suspicion:

• Common symptoms: Dyspnea on exertion, orthopnea, paroxysmal nocturnal dyspnea, persistent cough, marked pedal edema, and fatigue 3, 5
• Additional features: Abdominal discomfort from hepatic congestion, dizziness, chest pain, palpitations, and postural hypotension in advanced cases 3
• Critical pitfall: Women and clinicians often attribute these symptoms to normal pregnancy or postpartum fatigue, leading to delayed diagnosis 3, 7

Diagnostic Workup

Initial Testing

• Natriuretic peptides: BNP or NT-proBNP is elevated in every patient with PPCM and should be measured when clinical suspicion exists 2, 6
• 12-lead ECG: Abnormal in approximately 96% of patients, most commonly showing ST-T wave changes 2
• Chest X-ray: Demonstrates cardiomegaly in the majority of cases 1

Definitive Imaging

• Echocardiography: The gold standard for diagnosis, demonstrating LVEF < 45% 2, 6
• Left ventricular dimensions: May show LV end-diastolic dimension > 2.7 cm/m² body surface area, though this is not required for diagnosis 2
• Assess for complications: Look for left ventricular thrombus (occurs in 16-17% when LVEF < 30%) and right ventricular involvement 5, 2

Critical Differential Diagnoses

Pre-eclampsia with Pulmonary Edema

• Timing distinction: Pre-eclampsia complications typically occur before the postpartum peak of PPCM (2-62 days after delivery) 1
• Hypertension pattern: Severe hypertension in late pregnancy suggests pre-eclampsia rather than PPCM; exclude pre-existing severe hypertension 1
• Cardiac dimensions: Pre-eclampsia rarely causes the degree of ventricular dilation seen in PPCM 1

Pre-existing Cardiomyopathy Unmasked by Pregnancy

• Timing of presentation: Pre-existing cardiomyopathy typically presents by the second trimester, not in the last month or postpartum 1
• Cardiac dimensions: Larger ventricular dimensions suggest pre-existing disease rather than new-onset PPCM 1

Other Acute Cardiac Conditions

• Myocardial infarction: Extremely rare in young women without cardiovascular risk factors; progressive symptoms over time favor cardiomyopathy over acute coronary syndrome 1
• Valvular disease: Severe valvular disease causing acute decompensation would have been detected earlier in pregnancy or would have pre-existed with symptoms 1
• Pulmonary embolism: Must be excluded with appropriate imaging when dyspnea is acute 6

Risk Stratification by LVEF

High-Risk (LVEF < 30%)

• Mortality risk: Highest mortality and morbidity 5, 2
• Mandatory anticoagulation: Initiate therapeutic anticoagulation for 6-8 weeks postpartum due to 16-17% incidence of intracardiac thrombi 5, 2
• Advanced therapies: Early referral for LVAD or transplant evaluation 2

Moderate-Risk (LVEF 30-45%)

• Standard heart failure therapy: Managed with guideline-directed medical therapy and close follow-up 2
• Anticoagulation consideration: Consider anticoagulation based on additional risk factors (atrial fibrillation, documented thrombus) 2

Management Approach

Acute Heart Failure Therapy

Antepartum (before delivery):

• Diuretics: For volume overload and symptom relief; safe throughout pregnancy and lactation 2
• Beta-blockers: Carvedilol or metoprolol to lower myocardial oxygen demand 2
• Vasodilators: Hydralazine plus nitrates (ACE inhibitors are teratogenic and absolutely contraindicated) 2, 8
• Digoxin: Safe for rate control and inotropic support 8

Postpartum (after delivery):

• ACE inhibitors or ARBs: Start immediately after delivery to reduce afterload 2
• Aldosterone antagonists: Add when symptoms persist despite initial therapy 2
• Continue beta-blockers and diuretics as needed 2

Anticoagulation Strategy

Initiate therapeutic anticoagulation when:

• LVEF < 30-35% (continue for 6-8 weeks postpartum) 2
• Documented left ventricular thrombus on echocardiography or cardiac MRI 2
• Atrial fibrillation or other clinically significant arrhythmias 2
• Use subcutaneous heparin during pregnancy; warfarin or DOACs may be used postpartum if not breastfeeding 8

Monitoring and Follow-Up

• Serial echocardiography: Recommended at 6-8 weeks, 3 months, and 6 months to track recovery trajectory 2
• Recovery timeline: Approximately 78% of left ventricular functional recovery occurs within the first 4 months after delivery 2
• Cardiology follow-up: All women require close follow-up with a cardiologist, though optimal duration of therapy after complete recovery is unknown 7

Race-Specific Considerations

• African ancestry: Markedly higher incidence (1:1,421 vs 1:4,075 in White individuals), higher rates of persistent LV dysfunction, more severe initial presentations, and increased mortality in some regions 2
• Clinical implication: Lower threshold for aggressive intervention and intensified follow-up in African-ancestry patients 2

Counseling for Future Pregnancies

Absolute Contraindication

• Persistent LV dysfunction (LVEF < 50%): Subsequent pregnancy carries 48% risk of further LVEF decline, 49% risk of recurrent heart failure, and 16% mortality 5, 2

Relative Contraindication

• Complete recovery (LVEF ≥ 50%): Still carries 27% risk of LVEF deterioration and 32% risk of recurrent heart failure, though mortality is 0% 5, 2

Recommendations

• Permanent contraception or high-risk pregnancy counseling with pre-conception cardiology evaluation is recommended for all women with a history of PPCM, regardless of current LV function 2

Multidisciplinary Care

• Mandatory cardiology consultation for all suspected or confirmed cases 2, 7
• Cardio-obstetrics team: Include obstetrics, cardiology, maternal-fetal medicine, anesthesiology, and nursing 7
• Intensive care access: Required for patients with NYHA class III-IV symptoms, which represent the majority of cases 2