How does excess aldosterone increase blood pressure?
Normally, aldosterone production is regulated by a system that responds to blood volume and sodium levels. In primary hyperaldosteronism, this regulation is disrupted: adrenal cells produce the hormone autonomously. The kidneys begin to retain sodium and water, blood volume increases, blood vessels become more sensitive to constricting influences - pressure rises. At the same time, potassium is excreted in the urine and its level drops. Excess aldosterone directly contributes to fibrosis of the heart muscle and kidney damage, so complications develop faster than with normal hypertension at the same level of pressure.
- Autonomic production of aldosterone
- Sodium and water retention
- Potassium loss in urine
- Increased blood volume and pressure
- Direct damage to the heart and kidneys
Reasons and forms
There are two main forms. The first is unilateral: a benign tumor of one adrenal gland that produces aldosterone, called aldosteroma or Conn's syndrome. The second is bilateral hyperplasia, in which both adrenal glands work excessively. It is fundamentally important to distinguish between them, because the treatment is different: with a unilateral form, surgical treatment is possible, with a bilateral form, treatment is medicinal. Familial forms that begin at a young age are rare and require genetic testing.
- Unilateral aldosteroma
- Bilateral adrenal hyperplasia
- Rare family forms
- Very rare - malignant tumor
- Tactics depend on the side of the attack
Symptoms
The main manifestation is high blood pressure, which does not respond well to standard treatment and often requires three or more medications. Many patients report nothing other than this. With severe loss of potassium, muscle weakness, cramps in the calves, numbness and tingling, fatigue, and sometimes episodes of severe weakness in the arms and legs appear. Due to impaired kidney function, frequent urination, going to the toilet at night, and thirst are possible. Edema, contrary to expectations, usually does not occur.
- Persistently elevated blood pressure
- Muscle weakness and cramps
- Numbness and tingling
- Frequent and night urination
- Thirst
- Headache and fatigue
Diagnostics
The screening method is the ratio of aldosterone and renin in the blood. Blood is taken in the morning, following the preparation rules: the doctor adjusts the medications taken in advance, because many of them distort the result, and the potassium level is normalized if possible. If the result is positive, a confirmatory test is performed. Only after this a computed tomography scan of the adrenal glands is performed. Since small formations also occur in healthy people, to accurately determine the side of the lesion, a special blood test from the adrenal veins is often required, which is performed in specialized centers.
- Aldosterone-renin ratio
- Adjustment of medications before analysis as directed by a doctor
- Blood potassium and sodium
- Confirmation sample
- Computed tomography of the adrenal glands
- Blood sampling from the adrenal veins when planning surgery
Treatment
In case of unilateral form and confirmed side of the lesion, laparoscopic removal of the adrenal gland is performed. After surgery, potassium almost always returns to normal, and blood pressure decreases in most patients, although some continue to take medications, especially if hypertension has existed for many years. In the case of a bilateral form, drugs from the group of aldosterone antagonists are prescribed, which block its action; The doctor selects the dose, monitoring blood pressure, potassium and kidney function. Regardless of the form, salt restriction, weight loss and regular monitoring are important.
- Laparoscopic removal of the adrenal gland in unilateral form
- Bilateral aldosterone antagonists
- Monitoring potassium and renal function during therapy
- Limiting table salt
- Weight loss and physical activity
- Regular blood pressure measurement and monitoring by a cardiologist
