Assessment of serum phenylalanine and tyrosine isomers in patients with ST-segment elevation vs non-ST-segment elevation myocardial infarction.

Background: Under conditions of oxidative stress, hydroxyl radicals can oxidize phenylalanine (Phe) into various tyrosine (Tyr) isomers (meta-, ortho-, and para-tyrosine; m-, o-, and p-Tyr), depending on the location of the hydroxyl group on the oxidized benzyl ring. This study aimed to compare patients with ST-segment elevation myocardial infarction (STEMI) and non-STEMI (NSTEMI) and the serum levels of Phe and Tyr isomers at the aortic root and distal to the culprit lesion in both groups.

Methods: Forty-four patients participated in the study: 23 with STEMI and 21 with NSTEMI.