Cardiac Encephalopathy.
Many patients develop confusion, lethargy, and cognitive and behavioral abnormalities during or after cardiac decompensation. Congestive heart failure and the accompanying elevation in systemic venous pressure and decrease in cardiac output can lead to changes within the cranial cavity that cause an encephalopathy. At times, excess cerebrospinal fluid accumulates within the cranium causing an apathetic state identical to that seen in patients with other causes of hydrocephalus. Awareness of the syndrome of cardiac encephalopathy and optimal management of congestive heart failure and body fluids can reverse the neurologic dysfunction. In some patients with excess cerebrospinal fluid, lumbar puncture with removal of cerebrospinal fluid can reverse the apathetic state.