Post-partum myocardial ischemia due to intramuscular methylergonovine-induced coronary vasospasm: case report

Abstract

Background: Methylergonovine is a vasoconstrictive agent historically used as a provocative agent in the lab for coronary vasospasm; it is also a first line uterotonic agent for management of postpartum hemorrhage.

Case presentation: A 29-year-old female with history of smoking and idiopathic thrombocytopenia received intramuscular methylergonovine after delivery of twins for intrauterine hemorrhage management. Subsequently, she had episodes of chest pain with high sensitivity Troponin I elevation to 1509 ng/L with accompanying septal T wave inversions, decreased left ventricular ejection fraction to 49% and basal septal wall hypokinesis. Computed tomography (CT) coronary angiogram showed patent coronary arteries and no coronary arterial dissection. The patient was conservatively managed with aspirin and metoprolol, and on follow up had fully recovered left ventricular function with resolution of wall motion abnormalities. Given this, coronary vasospasm due to intramuscular methylergonovine is the most likely cause of patient's chest pain and associated myocardial ischemia.

Conclusions: Intramuscular, intrauterine, intravenous, and even oral methylergonovine can rarely cause coronary vasospasm leading to myocardial ischemia. Cardiologists caring for postpartum patients should be aware of these potential lethal complications; prompt identification and administration of sublingual nitroglycerin can prevent severe complications of arrythmias, heart block, or cardiac arrest.

Keywords: Case report; Coronary vasospasm; Postpartum methylergonovine.

Fig. 1

Initial electrocardiogram obtained at the time of chest pain showing T wave flattening in inferior and anterolateral leads, as well as premature ventricular contractions

Fig. 2

Repeat ECG at time of second episode of chest pain showed T wave inversions in septal leads