Cardiac encephalopathy and congestive heart failure: a hypothesis about the relationship.

Many patients with congestive heart failure develop neurologic dysfunction. This may take the form of a cardiac encephalopathy that shares clinical features with other metabolic encephalopathies. The causes are multiple. There is a particular, previously unreported, syndrome that occasionally develops in some patients with congestive heart failure that resembles the findings in patients with normal pressure hydrocephalus. This syndrome is characterized by apathy and abulia with preserved alertness; it is caused by fluid retention within the cranial cavity. The syndrome may also develop in patients with other conditions that cause anasarca, e.g., severe liver or kidney disease or hypoalbuminemia. Because patients with these conditions are often quite ill, it has been difficult to verify the pathophysiologic aspects of the syndrome so that its mechanism must remain a hypothesis that awaits more definitive study in a series of patients. I have not seen this syndrome discussed in any cardiology or neurology texts or reports, and it seems to be completely unknown to cardiologists and neurologists. I have recognized about one patient per year with this syndrome.