Carotid vascular remodeling in patients with pheochromocytoma

CONTEXT: The influence of catecholamines on vascular remodeling in humans was investigated. OBJECTIVE: The objective was to study the carotid vascular wall in patients with pheochromocytoma (PHEO). DESIGN AND SETTING: An observational study was conducted in a university referral center for blood pressure diseases. PATIENTS: Fourteen patients with PHEO, 15 matched high-normal essential hypertensives, 15 mild essential hypertensives, and 15 controls underwent two-dimensional conventional ultrasonography and ultrasonic tissue characterization of the carotid wall. MAIN OUTCOME MEASURES: Intimal media thickness (IMT), diameter, and corrected ultrasonic integrated backscatter signal (C-IBS) of carotid arteries were evaluated. RESULTS: IMT in PHEOs (0.844 +/- 0.18 mm, mean +/- sd) was greater than not only controls (0.596 +/- 0.09 mm, P < 0.0002) but also high-normal (0.710 +/- 0.17 mm, P < 0.03), and even mild (0.727 +/- 0.20 mm, P = 0.06) hypertensives. IMT in the latter was higher than in controls (P < 0.03), without difference in comparison with high-normal hypertensives. C-IBS values in PHEOs (-21.71 +/- 2.0 dB, mean +/- sd) were greater than in controls (-26.20 +/- 1.73 dB, P < 0.0001) but also than in high-normal (-23.84 +/- 1.16 dB, P < 0.002) and mild (-23.37 +/- 1.99 dB, P < 0.01) hypertensives. C-IBS values in controls were lower than in high-normal (P < 0.0005) and mild (P < 0.0001) hypertensives. Carotid diameter was not significantly different in the four groups. In PHEOs, C-IBS was associated with urinary noradrenaline (r = 0.640, P < 0.01) and normethanephrine (r = 0.737, P < 0.009). CONCLUSIONS: Carotid IMT of PHEOs is higher than in controls and matched groups of hypertensives with comparable or even higher blood pressure. This vascular rearrangement is characterized by increased IBS values due to collagen deposition and vascular fibrosis. Therefore, our data show that abnormal catecholamine levels take part per se in carotid wall remodeling of patients with PHEO.