Which condition presents with paroxysmal hypertension due to catecholamine release and typically does not cause a persistent inter-arm blood pressure difference?

• A. Abdominal aortic aneurysm.
• B. Pheochromocytoma.
• C. Coarctation of the aorta.
• D. Thoracic outlet syndrome.

Answer: (B)

Paroxysmal hypertension due to catecholamine release points to pheochromocytoma. The tumor in the adrenal medulla can dump catecholamines episodically, producing sudden spikes in blood pressure along with symptoms like headaches, sweating, and tachycardia. This pattern is systemic and episodic, not caused by a fixed obstruction or narrowing of a vessel.

A persistent inter-arm blood pressure difference is more suggestive of an anatomical or hemodynamic issue affecting flow to the upper extremities—conditions such as coarctation of the aorta or significant subclavian or aortic lesions—where the difference remains across episodes. Since pheochromocytoma causes episodic systemic hypertension rather than a constant unilateral vascular obstruction, it typically does not produce a lasting inter-arm BP disparity.

Other options fit different clinical pictures: an abdominal aortic aneurysm presents with risk factors and signs related to aorta pathology (pain, pulsatile mass) rather than catecholamine-driven surges; coarctation causes persistent differences and leg-predominant findings due to narrowed aorta above the ductus; thoracic outlet syndrome causes upper-extremity symptoms from nerve or vessel compression without the paroxysmal catecholamine-driven hypertension seen with pheochromocytoma.