Silent Culprit: Incidental Inferior ST-Elevation Myocardial Infarction on Triage Electrocardiogram in an Elderly Man Presenting With Dizziness

Silent or painless myocardial infarction is well described yet remains a diagnostic challenge, particularly in older adults and those with cognitive impairment, in whom classic anginal symptoms may be absent or difficult to report.We describe an 82-year-old man with hypertension, dyslipidemia, dementia, and coronary artery disease with prior percutaneous coronary intervention who was brought to the emergency department with dizziness and transient lower-extremity weakness after running out of and inconsistently taking his antihypertensive and lipid-lowering medications.He denied chest pain, dyspnea, and diaphoresis.A triage electrocardiogram unexpectedly revealed inferior ST-segment elevation with reciprocal ST-segment depression, prompting activation of a code for ST-elevation myocardial infarction.High-sensitivity troponin levels were markedly elevated.Emergent coronary angiography demonstrated total occlusion of an aneurysmal proximal-to-mid right coronary artery and multivessel disease involving the left coronary system.The culprit lesion was treated with a single drug-eluting stent, restoring normal coronary blood flow, while the residual multivessel disease was managed medically, with planned surgical revascularization.He recovered without hemodynamic compromise.This case underscores that a large, angiographically confirmed infarction may present with only nonspecific symptoms and that a low threshold for early electrocardiography in elderly patients, even those presenting for seemingly unrelated reasons, such as medication refills, can be lifesaving.Recognizing that dementia may mask or hinder communication of ischemic symptoms and addressing lapses in secondary-prevention therapy are essential for timely reperfusion and improved outcomes.