Answer
C: Peripartum cardiomyopathy
Educational Objective
Diagnose peripartum cardiomyopathy.
Critique
The most likely diagnosis in this woman who is 3 weeks postpartum is peripartum cardiomyopathy. Peripartum cardiomyopathy is left ventricular systolic dysfunction with onset toward the end of pregnancy or in the months following delivery in the absence of another identifiable cause. Although patients may be asymptomatic, they often present with features of heart failure. Women with peripartum cardiomyopathy should be promptly treated with medical therapy, which may include 尾-blockers, digoxin, hydralazine, nitrates, and diuretics. ACE inhibitors, angiotensin receptor blockers, and aldosterone antagonists are teratogenic and should be avoided until after delivery.
Acute aortic dissection classically presents with sudden onset of chest or back pain that has a tearing or ripping quality. Dyspnea is less common. Physical examination findings include a blood pressure or pulse differential between the upper extremities. A diastolic murmur of aortic regurgitation may be heard at the cardiac base if the aortic valve is involved. Echocardiography demonstrates an enlarged ascending aorta; the dissection flap may also be visible. Ventricular function is usually normal unless the aortic dissection has involved the coronary arteries, although regional abnormalities may be detected. This patient's clinical findings do not support a diagnosis of acute aortic dissection.
Pulmonary embolism can occur postpartum, particularly when prolonged bed rest is required during or following pregnancy. Patients with pulmonary embolism frequently present with dyspnea; however, this patient's presentation suggests heart failure, given the elevated venous pressure, pulmonary congestion, and global reduction in ejection fraction.
Takotsubo cardiomyopathy, also known as stress cardiomyopathy, is characterized by transient regional cardiac dysfunction, usually involving the apical and mid-portion of the left ventricle. It is usually precipitated by a stressful physical or emotional event. Postpartum cases of takotsubo cardiomyopathy have been reported, especially after cesarean delivery. Patients with takotsubo cardiomyopathy present with features that mimic an acute coronary syndrome: chest pain, ischemic electrocardiographic changes, and elevated cardiac biomarker levels. This patient's clinical picture is inconsistent with takotsubo cardiomyopathy.
Key Point
Peripartum cardiomyopathy is left ventricular systolic dysfunction with onset toward the end of pregnancy or in the months following delivery in the absence of another identifiable cause; patients often present with features of heart failure.
Bibliogrpahy
Arany Z, Elkayam U. Peripartum cardiomyopathy. Circulation. 2016;133:1397-409. [PMID: 27045128] doi:10.1161/CIRCULATIONAHA.115.020491