Case report: pheochromocytoma presenting as acute ST-segment elevation myocardial infarction without coronary artery abnormalities.

Pheochromocytoma can cause various cardiovascular complications, but presenting as acute ST-segment elevation myocardial infarction (STEMI) without coronary artery abnormalities is rare. We report the case of a young patient to highlight the associated diagnostic challenges. A 26-year-old female presented with acute chest pain, ST-segment elevation, and elevated cardiac enzymes. Coronary angiography revealed no stenosis. She developed severe heart failure with blood pressure variability (ranging from 153/120 mmHg to 60/40 mmHg). Laboratory results showed elevated catecholamine levels, and imaging identified a 9.7×7.6 cm adrenal mass. Histopathology confirmed pheochromocytoma. This case suggests that pheochromocytoma should be considered in young patients presenting with STEMI and heart failure without coronary lesions, particularly when accompanied by blood pressure variability. It offers a systematic differential diagnosis framework for distinguishing pheochromocytoma crisis from Takotsubo syndrome and acute myocarditis in emergency settings.