Inferior ST-elevation myocardial infarction associated with premature coronary atherosclerosis in a 21-year-old smoker: a case report.

BACKGROUND: ST-elevation myocardial infarction (STEMI) in very young adults is rare and is commonly attributed to non-atherosclerotic mechanisms. Atherosclerotic coronary artery disease in this age group is exceptional and warrants thorough evaluation of contributing risk factors. The increasing prevalence of electronic cigarette use among young individuals raises concern regarding its potential role in premature coronary atherosclerosis. CASE SUMMARY: A 21-year-old man presented with a 3-h history of typical anginal chest pain. He had a significant history of combined tobacco cigarette and electronic cigarette use for more than 5 years. Electrocardiography demonstrated ST-segment elevation in the inferior leads, consistent with inferior STEMI. Laboratory testing revealed elevated troponin I, leukocytosis, and prediabetes (HbA1c 6.2%). Coronary angiography identified an atherosclerotic culprit lesion with ∼80% stenosis and thrombus formation in the mid-right coronary artery. The patient underwent successful primary percutaneous coronary intervention with TIMI grade III flow. Transthoracic echocardiography showed preserved left ventricular systolic function. Further evaluation excluded autoimmune and secondary thrombotic aetiologies. The patient recovered well, was discharged on guideline-directed medical therapy, and remained asymptomatic at 3-month follow-up without recurrent ischaemic events. DISCUSSION: This case highlights premature atherosclerotic STEMI in a very young adult without established cardiovascular disease or autoimmune aetiology. Chronic exposure to combustible and electronic cigarettes has been associated with endothelial dysfunction and vascular inflammation, which may contribute to accelerated atherosclerosis. Clinicians should maintain a high index of suspicion for atherosclerotic myocardial infarction in young patients with significant nicotine exposure and emphasize early prevention and cessation strategies in accordance with current European Society of Cardiology guidelines.