Adrenal Venous Sampling Using Metanephrine in Primary Aldosteronism With or Without Cortisol Cosecretion.

Area of Science:

• Endocrinology
• Medical Diagnostics

Background:

• Adrenal venous sampling (AVS) is crucial for lateralizing aldosterone secretion in primary aldosteronism (PA).
• The utility of plasma metanephrine in AVS for PA lateralization requires further investigation.

Purpose of the Study:

• To assess the effectiveness of plasma metanephrine in AVS for determining aldosterone lateralization in PA.
• To evaluate its performance with and without mild autonomous cortisol secretion (MACS).

Main Methods:

• Conducted sequential AVS under cosyntropin stimulation in 58 PA patients.
• Assessed selectivity index using plasma metanephrine (SIMN) and cortisol (SIC).
• Calculated lateralization index using metanephrine (LIA/MN) and cortisol (LIA/C).

Main Results:

• Plasma metanephrine demonstrated superior selectivity compared to cortisol.
• High correlation between metanephrine and cortisol for both selectivity and lateralization indices.
• Metanephrine-based lateralization was concordant in 93.1% of cases.
• MACS generally did not affect lateralization outcomes.

Conclusions:

• Plasma metanephrine is a reliable marker for assessing selectivity in AVS for PA.
• Metanephrine is equivalent to cortisol for determining aldosterone lateralization.
• AVS under cosyntropin stimulation is effective for lateralization, with MACS having minimal impact in most PA cases.