Lymphocytic Myocarditis In The Late Preterm Patient

Background:  This patient was transferred to us at 35 weeks gestation with gastroenteritis symptoms and suspected preeclampsia.  Further evaluation revealed this to be more than a simple case of preeclampsia.  Multiple differential diagnoses were considered.

Case: Physical exam was unremarkable on admission.  Patient had complaints of headache,nausea, blood pressure was normal and viral gastroenteritis suspected.  Symptoms improved after administration of both antiemetics and antacids.  Subsequently, the patient became febrile, oliguric and developed epigastric pain.  Abdominal MRI was unremarkable, pancreatitis was ruled out by abdominal ultrasound, and the hepatitis panel was negative.  She  then developed a diffusely tender abdomen, chorioamnionitis suspected, antibiotics started and induction of labor initiated.

After initiation of induction, dyspnea noted and a chest x-ray was obtained to rule out pneumonia.  She remained febrile, hypotensive, tachycardic and tachypneic throughout labor, but had a spontaneous vaginal delivery and the infant was transferred to NICU.

No improvement in symptoms occurred following delivery.  Concerns for worsening pneumonia and the potential for developing pulmonary edema led to an EKG, repeat chest x-ray, blood, urine and placental cultures, PIH labs, cardiac enzymes, arterial blood gases, and an echocardiogram.  An arterial line was placed and a diuretic administered.

Cardiology was consulted and the patient was transferred to cardiac cath lab.  Cardiac catheterization was done and endomyocardial biopsies obtained. Coronary arteries were patent and the ejection fraction found to be less than 10%.  She developed ventricular fibrillation, was defibrillated twice,  stabilized, and placed on ECMO.  An aortic balloon pump was inserted in the OR.

She was transported to CICU for further management.   Cardiology determines  that a biventricular assist device (BIVAD) will be required for a prolonged period, to allow time for myocardial recovery since her myocardial biopsies reveal lymphocytic myocarditis.  Her aortic balloon pump was removed and she was transferred out for BIVAD placement and further evaluation.

Conclusion: Acute Lymphocytic Myocarditis is rare, difficult to diagnose, except by biopsy, and is usually an immune response to viral infection.  Case reports in pregnancy are almost nonexistent.  Our L&D unit routinely cares for pre-eclamptic patients, and her preliminary lab results determined routine care.  Persistence of her symptoms indictated need for further testing which revealed significant abnormalities, prompting additional testing for less common alternate diagnoses. Ultimately, her rare diagnosis of Acute Lymphocytic Myocarditis was determined after delivery. We learned that pregnancy can complicate and conceal a variety of ailments.  Symptoms as common as unresolved persistent nausea and vomiting, tachycardia, and tachypnea requires further testing which in turn may lead the healthcare team to eliminate additional differential diagnoses.  A well-coordinated interdisciplinary team working together makes a great impact on the outcome for the mother-baby unit.

Keywords: lymphocytic myocarditis, pregnancy