BAX and depressive symptom measurement: This study aimed to attempt to evaluate vulnerability markers of myocardial apoptosis, specifically the Bax:Bcl-2 ratio and caspase-3 levels in the myocardium post-MI depression, to clarify the molecular mechanisms and, as well, confirm whether the co-occurrence of myocardial infarction with MDD is associated with greater activation of apoptosis pathways.