Normotensive Palpitations in Primary Care Unmasking Pheochromocytoma Complicated by Reversible Cerebral Vasoconstriction Syndrome: A Case Report.

Pheochromocytomas and paragangliomas (PPGLs) are rare catecholamine-secreting neuroendocrine tumors with intermittent and nonspecific manifestations that may be initially encountered in primary care. Although paroxysmal or sustained hypertension is a classic clue, some patients remain normotensive between episodes, which contributes to diagnostic delay. Reversible cerebral vasoconstriction syndrome (RCVS) is an important cause of thunderclap headache and may be complicated by cortical (convexity) subarachnoid hemorrhage (cSAH). Catecholamine excess is a recognized, treatable trigger of cerebral vasoconstriction and hemorrhagic/ischemic neurovascular events. We report a 50-year-old man followed in primary care for recurrent palpitations occurring 3-4 times per week with normal office blood pressure (BP) who later presented with thunderclap headache, and cSAH attributed to RCVS, with elevated BP at emergency presentation. Etiologic evaluation demonstrated markedly elevated plasma-free metanephrines and a hypervascular right adrenal mass consistent with pheochromocytoma. After guideline-concordant preoperative preparation with alpha-adrenergic blockade followed by beta-blockade, the patient underwent laparoscopic right adrenalectomy with a favorable perioperative course and biochemical remission on follow-up. This case highlights the pivotal role of primary care clinicians in the early recognition of PPGLs. Recurrent palpitations and other adrenergic spells should raise clinical suspicion and prompt diagnostic consideration even when hypertension is not documented. In a setting where primary care manages a large number of patients with established or newly diagnosed hypertension, timely biochemical testing and appropriate referral are essential to prevent severe, potentially life-threatening complications.