[Changes in water-electrolyte balance and central hemodynamics in hypertensive crises]

Area of Science:

• Nephrology
• Cardiology
• Endocrinology

Background:

• Essential hypertension is a common condition affecting cardiovascular and renal health.
• Hypertensive crises represent a severe exacerbation of the disease, necessitating further investigation into underlying mechanisms.
• Understanding fluid and electrolyte balance is crucial in managing hypertensive patients.

Purpose of the Study:

• To investigate sodium, potassium, and water distribution in hypertensive crises.
• To analyze central hemodynamic parameters and hormonal activity (plasma renin activity, aldosterone) in patients with and without hypertensive crises.
• To explore the relationship between disease severity, sodium metabolism, and hormonal changes in female hypertensive patients.

Main Methods:

• Cross-sectional study involving 48 patients with stable essential hypertension and 18 controls.
• Exclusion of patients with heart or renal failure.
• Measurement of fluid balance, hemodynamic parameters, plasma renin activity, and aldosterone levels.

Main Results:

• Female patients experiencing hypertensive crises exhibited elevated extracellular fluid and plasma sodium levels.
• These patients also showed higher total peripheral resistance and lower cardiac output compared to crises-free patients.
• A significant 3.3-fold reduction in plasma renin activity was observed in female patients with crises, while aldosterone levels remained unchanged.
• A direct correlation was found between the recurrence of crises and increased total peripheral resistance.

Conclusions:

• Hypertensive crises in female patients are associated with significant alterations in sodium metabolism and hormonal regulation.
• Reduced plasma renin activity, despite increased sodium retention, suggests complex pathophysiological mechanisms.
• The findings underscore the importance of monitoring fluid balance and hormonal status in managing severe hypertension.