Phenelzine-induced myocardial injury: a case report.
BACKGROUND
Phenelzine is an irreversible monoamine oxidase inhibitor (MAOI). Hypertensive reactions after ingestion of tyramine-rich foods such as cheese are well known. However, a review of the available medical literature found no previous reports of myocardial infarction resulting from the ingestion of cheese by a patient taking a MAOI.


METHODS
A 34-year-old female taking phenelzine for depression developed severe chest pain 1 h after eating cheese. She was hypertensive and the electrocardiography showed ischemic changes in the antero-lateral chest leads. The chest pain and elevated blood pressure were relieved with intravenous morphine and nitroprusside. The initial serum troponin I level was normal, but serial repeat levels showed a rising trend with a peak at 4.89 ug/L (reference range <0.05 ug/L) 6 h after the initial blood draw, suggestive of a non-ST elevation myocardial infarction. The patient subsequently developed hypotension 4 h after another therapeutic dose of phenelzine was served to the patient 4 h after her admission to the ED. This was corrected with at least 2 L of intravenous normal saline boluses. Subsequent EKGs and Sestamibi scan showed no evidence of cardiac ischemia. She was discharged home after a hospital stay of 3 days.


CONCLUSIONS
We believe this to be the first reported case of myocardial infarction resulting from ingestion of cheese in a patient taking a MAOI. It might be expected that hypertensive crisis could lead to a myocardial infarction, but a review of the medical literature found no such cases reported.
Ngo
Adeline Su-Yin
AS
Department of Emergency Medicine, Singapore General Hospital, Outram Road, Singapore, 169608, Singapore. angosy@gmail.com
Ho
Raymond Y
RY
Olson
Kent R
KR
D000328:Adult; D002611:Cheese / Q000009:adverse effects*; D002637:Chest Pain / Q000188:drug therapy / Q000209:etiology / Q000503:physiopathology; D004562:Electrocardiography; D005260:Female; D018565:Food-Drug Interactions; D006321:Heart / Q000187:drug effects / Q000503:physiopathology; D006801:Humans; D007275:Injections, Intravenous; D008996:Monoamine Oxidase Inhibitors / Q000009:adverse effects*; D009020:Morphine / Q000627:therapeutic use; D009203:Myocardial Infarction / Q000097:blood / Q000139:chemically induced* / Q000503:physiopathology; D009599:Nitroprusside / Q000627:therapeutic use; D010624:Phenelzine / Q000009:adverse effects*; D016896:Treatment Outcome; D019210:Troponin I / Q000097:blood; D014665:Vasodilator Agents / Q000627:therapeutic use
D008996:Monoamine Oxidase Inhibitors; D019210:Troponin I; D014665:Vasodilator Agents; D009599:Nitroprusside; D009020:Morphine; D010624:Phenelzine