The clinical problem of brain and heart.

Observations in an intensive care stroke unit showed that patients recovering from stroke sometimes perish unexpectedly from cardiac complications or sudden death. Compared with control subjects, stroke patients more often have cardiac arrhythmias, raised cardiac enzymes, and elevated plasma norepinephrine, suggesting a hypersympathetic state. We have found that involvement of the insula by experimental cerebral infarction is crucial in mediating the cardiac complications. Age and right as opposed to left hemisphere involvement represent additional risks for the cardiac complications of experimental stroke. These experimental observations now need to be tested clinically.