A 35-year-old African American woman with past medical history of systemic lupus erythematosus and hemolytic anemia and who was postpartum from a spontaneous vaginal delivery a month earlier presented with chest pain and shortness of breath that had started the day before. She described her pain as a pressure in the center of the chest, nonradiating, and unchanged with activity.
She denied fever or chills, and said she had never had pain like this. She also denied leg pain or edema of the legs, and ever having a blood clot, pulmonary embolism, or syncope. She reported a dry cough associated with her chest pain. This was her first time being seen for her symptoms. A review of systems also revealed fatigue and lightheadedness.
The patient was sitting up in bed breathing comfortably with mild tachypnea. Triage vitals demonstrated a blood pressure of 179/103 mm Hg, tachycardia of 139 bpm, respiratory rate of 28 bpm, 95% on room air, and no fever. Her physical exam revealed tachycardia with a regular rhythm, no murmurs, intact distal pulses, and overall normal perfusion with warm extremities. Lung sounds were mildly diminished in bases with no wheezing. The remainder of her physical exam was normal.
Labs and CT of the chest with contrast were ordered. CBC returned with a hemoglobin and hematocrit of 9.0/29.9 (her baseline), a bicarbonate of 18, and an elevated high-sensitivity troponin assay to 55, which increased to 65 an hour later. Her troponin T was normal. Her NT-proBNP was pending, and a two-view chest x-ray was interpreted by radiology. Right lower lobe airspace opacities were suggestive of an infectious or inflammatory process. Her ECG revealed sinus tachycardia, right axis deviation, with no acute ischemic signs. Bedside echo showed moderately diminished ejection fraction without pericardial effusion.
When the patient was brought to radiology for a CT PE study, she was unable to tolerate lying flat and had acute onset worsening of her tachypnea and respiratory distress. She was found to be newly hypoxic, requiring 6 L NC oxygen and was brought back to the department because the CT scan was unable to be completed. Cardiology was consulted, and a bedside echo was performed, which showed decreased global and left ventricular function without significant right heart strain. She was started on a heparin infusion in the ED for presumed PE, and was admitted to the ICU.
Find the diagnosis and case discussion on p. 28.
Diagnosis: Postpartum Cardiomyopathy
The patient continued to have worsening respiratory distress while in the ICU. Her BNP returned at >21,000. She was unable to maintain her oxygen saturation, and developed worsening tachypnea requiring endotracheal intubation. Cardiology was called, and the patient was started on venoarterial ECMO with an Impella device placed secondary to worsening cardiac function with the left ventricle ejection fraction (EF) at 15%.
She was diagnosed with postpartum cardiomyopathy, or peripartum cardiomyopathy (PPCM), a condition in which a pregnant woman with no cardiac history develops systolic heart failure. (Criteria listed in the table; JAMA 2000;283:1183.) There are multiple estimates of the frequency of the disease, from one in 3,000 to one in 968. (Am J Cardiol 2006;97:1765.). Risk factors include increased maternal age, multigestational pregnancy, Afro-Caribbean race, multiple pregnancies, prolonged tocolytic therapy, and hypertensive diseases like pre-eclampsia. (Clin Med [Lond] 2017;17:316.) Mortality can be as high as 60 percent secondary to thromboembolic events and severe pulmonary edema. (Can J Anaesth 1999;46:1146.)
Patient presentation will likely be nonspecific for PPCM and may mimic late stages of a normal pregnancy. Symptoms such as dyspnea on exertion, orthopnea, and fatigue will be the primary complaints. Exam will often reveal sinus tachycardia, elevated jugular venous pressure, pulmonary edema, peripheral edema, and an S3 heart sound.
Diagnostic studies are closely related to general congestive heart failure. An ECG will generally reveal non-specific T wave changes and tachycardia. BNP will likely be elevated. A chest x-ray may show signs of pulmonary edema or pleural effusions. An echo will display a global or left-sided decrease in function with an EF under 45%. (Eur J Heart Fail 2010;12:767.)
Management of PPCM with acute decompensation is similar to that for patients presenting with heart failure from other causes. Assisted ventilation and oxygen support may be needed in conjunction with the optimization of preload. Diuretics can be administered whether the patient is pregnant or postpartum. Monitor for signs of dehydration and placental insufficiency. Additionally, angiotensin-converting-enzyme inhibitors can be used for afterload reduction but only in the postpartum period. Intravenous vasodilators such as nitroglycerin and nitroprusside can be used with caution and only when maternal well-being outweighs the risks. Patients with significantly depressed EF may benefit from anticoagulation as well to prevent emboli and thrombosis.
Our patient suffered cardiogenic shock, and her hospital course was complicated by PEA arrest, ECMO, and continuous renal replacement therapy. She had a prolonged hospital stay, but was ultimately removed from ECMO when her EF improved to 47%. She was discharged to a skilled nursing facility neurologically intact. Etiology of her heart failure was presumed to be PPCM because there was no evidence of lupus flare, myocarditis, or sepsis during hospitalization.
Criteria for Peripartum Cardiomyopathy
- Cardiac failure in the last month of pregnancy or within five months of delivery
- Absence of recognizable heart disease before the last month of pregnancy
- Absence of an identifiable cause for cardiac failure
- Left ventricular dysfunction (EF < 45%)