Myocardial Injury from Tranylcypromine-Induced Hypertensive Crisis Secondary to Excessive Tyramine Intake

Monoamine oxidase inhibitors (MAOIs) are known to cause hypertensive crisis when combined with intake of tyramine, classically found in cheese. We present a case of MAOI-induced hypertensive crisis leading to significant troponin release after soft cheese intake. A 51-year-old lady presented with left-sided chest pain, palpitations and headache in the context of significant hypertension after eating soft cheese. She had a similar episode 2 month prior to this presentation, which resulted in a diagnosis of non-ST elevation myocardial infarction after a troponin of 2768 ng/L (Ref < 17 ng/L) with normal cardiac investigations and CT pulmonary angiogram. She was known to be on tranylcypromine for bipolar depression. Subsequent cardiac investigations were normal, as were those for phaeochromocytoma and Conn’s disease. Tranylcypromine is a non-selective irreversible MAOI used in refractory depression and bipolar disorder. MAOIs are known to cause hypertensive crisis when combined with soft cheese due to unopposed release of catecholamines from reduced tyramine metabolisation, leading to injury and possible myonecrosis. Three previous case reports have demonstrated either creatinine kinase or troponin rise with myocardial infarction due to this hypertensive crisis and our case is the fourth with significant hypertension and cardiac biomarker rise related to MAOI, specifically tranylcypromine.