Chapter 13: Peripartum Cardiomyopathy

PATIENT CASE

A 29-year-old Caucasian woman presents to the emergency department 5 days post delivery with complaints of dyspnea and fatigue for 2 days. She reports it to be her first pregnancy, the course of which was complicated with gestational hypertension (HTN) (without other features of preeclampsia), and dependent bilateral pedal edema. She was treated with labetalol 200 mg by mouth twice a day for gestational HTN during her antepartum period. On physical examination, she was found to be dyspneic with respiratory rate of 25 breaths per minute and hypoxic with 80% saturation on room air. She was afebrile and had a blood pressure of 156/88 mm Hg and a pulse rate of 98 beats per minute. Her neck examination demonstrated a jugular venous distention of 17 cm water and grade 2+ pedal edema on both lower extremities. On systemic examination, lungs had diffuse bilateral inspiratory crackles; cardiac examination demonstrated regular heart rate with an S₃ summation gallop. No calf tenderness was observed and the rest of her physical examination was unremarkable.

Her laboratory investigation demonstrated urinalysis negative for protein. Cardiac enzymes, D-dimer, and thyroid function were within normal range and antinuclear antibodies were absent. The circulating levels of B-type natriuretic peptide (BNP) were 864 pg/mL. An electrocardiogram (ECG) showed a normal sinus rhythm with no conduction delays and no ectopy. Chest radiograph showed cardiomegaly with increased vascular congestion bilaterally (Figure 13-1). A computed tomography (CT) chest scan with contrast was negative for pulmonary embolism, but did show small bilateral pleural effusions and cardiomegaly. Subsequently an echocardiogram was obtained, which showed an ejection fraction (EF) of 35%.

DIFFERENTIAL DIAGNOSIS

At this point, the patient appears to have a new onset congestive heart failure (HF). The differential diagnosis to consider includes:

1. Peripartum cardiomyopathy (PPCM)

2. Cardiomyopathy including dilated, hypertrophic, or restrictive

3. Myocardial infarction

4. Pulmonary embolism (less likely given a negative CT scan)

5. Other cardiomyopathies: Drug-induced (alcoholic or cocaine-induced, although our patient denies usage of both)

6. Valvular heart disease (rheumatic mitral stenosis, aortic stenosis)

7. Noncardiogenic pulmonary edema

8. Primary pulmonary disease (asthma, chronic obstructive pulmonary disease, pulmonary fibrosis)

9. Others, including: Arrhythmogenic right ventricular dysplasia; infiltrative cardiac disease; toxic or metabolic disorders.

The diagnosis of PPCM is often missed as the signs and symptoms of a normal pregnancy coincide with findings of HF. These findings include dyspnea, dizziness, orthopnea, and decreased exercise capacity. Patients often do not show any indication of the syndrome until after delivery. Elkayam et al¹ and Sliwa et al² showed that patients could manifest similar symptoms even before the last gestational month and hence represent a continuum in the spectrum of this disease. The diagnostic criteria for peripartum cardiomyopathy are as follows: development of cardiac failure in ...