Water and Electrolytes Content in HYpertension (WHYSKI) in the SKIn

This study is investigating how salt (sodium) and water are stored in the skin of people with high blood pressure, particularly those with a specific type called primary aldosteronism (PA), where the adrenal gland overproduces a hormone that causes salt retention. Researchers will use a specialized MRI technique to measure sodium in the skin and see if it differs from people with regular high blood pressure. **You may be eligible if...** - You are between 18 and 75 years old - You have been diagnosed with primary aldosteronism (confirmed by blood tests and adrenal vein sampling) OR you have essential hypertension (regular high blood pressure, either on medications or confirmed by blood pressure monitoring) **You may NOT be eligible if...** - You have secondary hypertension from causes other than primary aldosteronism (for the PA group) - You have a condition that prevents MRI scanning (e.g., pacemaker, metal implants) - You are pregnant - You have severe kidney or liver disease Talk to your doctor to see if this trial is right for you.