Background: Transient ST-elevation myocardial infarction (STEMI) is a rare and underrecognized subset of acute coronary syndrome. It is characterized by the spontaneous resolution of ST-segment elevation before any reperfusion intervention. Although this phenomenon may indicate a more favorable prognosis, the underlying coronary pathology often persists, which raises questions regarding optimal management strategies.
 
Case Presentation: A 56-year-old man with a history of dyslipidemia and chronic smoking presented with acute epigastric pain. The initial ECG showed no ischemic changes; however, a repeat ECG 1 hour later demonstrated transient ST-segment elevation in the inferior leads that resolved spontaneously within minutes. Despite the resolution, the patient underwent urgent coronary angiography, which revealed an occlusion of the mid–right coronary artery. Successful revascularization was achieved with primary percutaneous coronary intervention and drug-eluting stent placement. The patient recovered without complications, had preserved cardiac function on echocardiography, and was discharged on optimal medical therapy.
 
Discussion: This case exemplifies the diagnostic and therapeutic challenges associated with transient STEMI, a condition with features overlapping those of both STEMI and high-risk non-STEMI. Although the ST-segment elevation is transient, it may mask ongoing myocardial injury or a critical coronary obstruction. Despite spontaneous reperfusion, the risk of adverse outcomes remains significant. Evidence supports the use of an early invasive management strategy to mitigate myocardial damage and prevent recurrent ischemia.
 
Conclusion: Transient STEMI should not be dismissed as a benign condition. Prompt recognition, serial ECG monitoring, and early revascularization remain essential. Further research is needed to establish standardized diagnostic criteria and optimal treatment strategies for this unique presentation of acute coronary syndrome. (Iranian Heart Journal 2025; 26(4): 98-104)