To the Editor:—
The anesthesiology literature describing coronary spasm after intravascular injection of an ergot alkaloid used for the treatment of uterine atony is limited to one case report. 1I herein report a similar case in association with intramyometrial injection of the drug. An otherwise healthy (there were, specifically, no coronary risk factors) 36-year-old white woman (height, 165 cm; weight, 71 kg; gravida 2, para 1) at 39 weeks’ gestation required an elective repeat cesarean delivery for fetal macrosomia, which was conducted under spinal anesthesia. After the uneventful delivery of the fetus and despite uterine massage and a continuous intravenous oxytocin infusion, the uterus remained atonic. A single intramyometrial injection of 0.2 mg methylergonovine maleate was administered by the obstetrician. The patient reported the almost immediate onset of a severe left-sided substernal chest pain, radiating to her left arm, and shortness of breath. Blood pressure was 110/61 mmHg, heart rate was 86 beats/min, respiratory rate was 18 breaths/min, and oxygen saturation was 100%. The electrocardiogram revealed normal sinus rhythm with nonspecific T-wave abnormalities and transient ST-segment elevation. The rapid onset of chest pain after administration of Methergine (Novartis Pharmaceuticals, East Hanover, NJ) and the patient’s report of chest tightness after a drug given to help the uterus contract at the time of her first cesarean delivery (which had not been conveyed to the anesthesiologist and the obstetrician before the current event) led, in this case, to the prompt diagnosis and immediate treatment of myocardial ischemia. The clinical symptoms (chest pain) and the electrocardiographic changes were reversed with intravenous injection of 3.5 μg/kg nitroglycerin, for a total dose of 250 μg. A postoperative 12-lead electrocardiogram and creatine phosphokinase enzyme analysis did not show any evidence of myocardial ischemia or infarction, and cardiology evaluation was noncontributory. Ergot derivatives can induce coronary spasm, and their use as a diagnostic agent in cardiac catheterization laboratories is well established. Nitroglycerin can be useful in reversing Methergine-induced coronary spasm and preventing subsequent development of myocardial ischemia and infarction. 1Although other conditions, such as esophageal spasm, are known to mimic angina and are accompanied by nonspecific electrocardiographic changes, the onset of clinical symptoms of left-sided substernal chest pain, radiating to the left upper extremity, with associated shortness of breath, and electrocardiographic changes almost immediately after intramyometrial administration of Methergine suggest cardiac etiology (coronary vasospasm). In addition, the patient’s admission of a similar symptomatology after the previous administration of ergot alkaloids should not be ignored. Because the myometrium is a highly vascular tissue, the intramyometrial injection of methylergonovine maleate might behave as an intravascular injection (which is not routinely recommended in the obstetric patient population). In conclusion, it is difficult to speculate whether different outcomes would have been reported (cardiovascular morbidity as described by Tsui et al. 1) if the diagnosis (based in this case primarily on clinical symptoms) and nitroglycerin injection to reverse the coronary spasm had been delayed.
