[Sympathetic nervous activity in cirrhosis: the relationship between peripheral hemodynamics and renal function...

Area of Science:

• Nephrology
• Cardiology
• Hepatology

Background:

• Cirrhosis is associated with complex hemodynamic alterations.
• Sympathetic nervous system (SNS) overactivity is a hallmark of advanced liver disease.
• The interplay between SNS activity, renal function, and vasodilation in cirrhosis requires further elucidation.

Purpose of the Study:

• To investigate the relationship between SNS activity and systemic/peripheral hemodynamics, renal function, and antinatriuretic activity in cirrhotic patients.
• To identify factors contributing to sympathetic hyperactivity in cirrhosis.

Main Methods:

• Studied 30 cirrhotic patients and 8 healthy controls.
• Measured plasma catecholamines (noradrenaline, adrenaline, dopamine), renin activity, aldosterone, mean arterial pressure, cardiac output, blood volume, right femoral arterial flow (RFAF), and renal function parameters.
• Assessed cyclic GMP urinary excretion (cV-UGMP) as an index of nitric oxide production.

Main Results:

• Higher plasma noradrenaline levels were observed in cirrhotic patients compared to controls.
• Plasma noradrenaline correlated with vasopressor systems, RFAF, cV-UGMP, Pugh score, creatinine clearance, and urinary sodium excretion.
• Right femoral arterial flow, creatinine clearance, and plasma adrenaline were independently associated with plasma noradrenaline levels.
• Plasma noradrenaline was elevated in patients with hyperdynamic circulation.

Conclusions:

• Extrasplanchnic vasodilatation significantly contributes to sympathetic nervous hyperactivity in cirrhosis.
• This sympathetic hyperactivity plays a crucial role in the renal function abnormalities observed in cirrhotic patients.