Abstract
BACKGROUND: Pheochromocytoma, a rare catecholamine-secreting tumor, typically presents with the classic triad of headache, palpitations, and diaphoresis, often accompanied by cardiovascular manifestations. While vomiting occurs in approximately 34.5% of cases, it is rarely the predominant and persistent presenting symptom. Pheochromocytoma-induced cardiomyopathy leading to heart failure is a recognized but uncommon complication. Due to its heterogeneous presentations, misdiagnosis and diagnostic delay are frequent. CASE SUMMARY: A 53-year-old female presented predominantly with persistent and refractory vomiting as her chief complaint, accompanied by signs of acute heart failure [left ventricular ejection fraction (LVEF) 30%]. Initial evaluation at a primary hospital, including coronary angiography (revealing only mild stenosis), led to a misdiagnosis of coronary artery disease. Despite standard anti-thrombotic, anti-heart failure, and anti-emetic therapy, her vomiting persisted and heart failure did not resolve. Subsequent hospitalization revealed dramatic paroxysmal hypertension (202/129 mmHg to 97/51 mmHg) and fever. Significantly elevated plasma metanephrines and normetanephrine, combined with abdominal computed tomography and magnetic resonance imaging, confirmed a right adrenal pheochromocytoma. This diagnosis was significantly delayed due to the atypical prominence of gastrointestinal symptoms masking the underlying endocrine crisis. CONCLUSION: This case highlights a highly atypical presentation of pheochromocytoma dominated by refractory vomiting and complicated by acute catecholamine-induced cardiomyopathy. It emphatically underscores that pheochromocytoma must be considered in the differential diagnosis for patients presenting with unexplained, treatment-resistant vomiting, particularly when co-existing with acute heart failure. The presence of labile hypertension, even if not initially evident, provides a crucial diagnostic clue. Prompt biochemical screening (catecholamine metabolites) and adrenal imaging are essential to prevent diagnostic delay and enable timely, life-saving surgical intervention.