When chest pain and troponin elevation aren’t acute coronary syndrome: a cardiovascular case report of atypical pheochromocytoma

Background: Pheochromocytoma is a rare catecholamine-secreting tumour with diverse cardiovascular manifestations. Presentation with chest pain and troponin elevation may closely mimic acute coronary syndrome (ACS), potentially leading to diagnostic delay. Case summary: We report the case of a 44-year-old woman who presented to the emergency department with acute chest pain and elevated cardiac biomarkers. Electrocardiography showed sinus rhythm with diffuse T-wave inversions, and high-sensitivity troponin levels were markedly elevated, leading to an initial diagnosis of non-ST-segment elevation myocardial infarction. Urgent coronary angiography, however, revealed angiographically normal coronary arteries. Cardiac magnetic resonance imaging demonstrated regional wall motion abnormalities without myocardial oedema or late gadolinium enhancement, excluding myocarditis and Takotsubo cardiomyopathy and suggesting a non-ischaemic mechanism of myocardial injury. The association of paroxysmal hypertension and adrenergic symptoms prompted further investigation, revealing markedly elevated plasma metanephrines, while abdominal imaging identified a left adrenal mass consistent with pheochromocytoma. Following adequate preoperative alpha- and beta-adrenergic blockade, the patient underwent successful surgical resection, resulting in complete clinical and cardiovascular recovery. Discussion: This case highlights the diagnostic challenge posed by pheochromocytoma presenting as ACS in the absence of obstructive coronary artery disease. It emphasizes the importance of reconsidering alternative diagnoses in patients with myocardial injury and normal coronary angiography, particularly when adrenergic symptoms are present.