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Updated: Oct 6, 2026

Quantitative Autonomic Testing
Published on: July 19, 2011
Rapid cyclic fluctuations of blood pressure associated with an adrenal pheochromocytoma
Abstract:
We present a patient with an adrenal pheochromocytoma with an unusual pattern of periodic alternating hypertension and hypotension. Alpha-adrenergic blockade alone failed to affect this pattern, which was abolished only after fluid repletion. The efficacy of volume expansion in ultimately correcting the wide fluctuations of blood pressure implicates a possible reflex neurogenic mechanism for the cyclic changes in blood pressure attributable to intravascular volume contraction.
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