Cognitive Deficits Linked to Bypass Surgery

A study has provided evidence linking cardiopulmonary bypass surgery to impaired memory and attention as well as evidence that this cognitive decline persists beyond the first few weeks. The study was published in the July 2002 issue of Neuropsychology.

Researchers studied cognition in 39 patients, several days before and three to four weeks after elective bypass surgery. They also analyzed test data from 49 healthy controls. The two groups showed significantly different neuropsychologic performance, both before and after the surgery. The researchers attribute the patients' lower presurgery memory scores to anxiety, medically based declines or both. In the testing that followed surgery, controls significantly outperformed bypass patients on two important tests of attention and memory. The data show that brain systems that support attention may be especially vulnerable.

"The medical aspect might be key, especially because it now seems as if some of the disease processes involved in coronary artery disease may be the same as those involved in dementias, including Alzheimer's disease,” said Julian Keith, Ph.D., department of cardiopulmonary bypass surgery at the University of North Carolina at Wilmington (DE, USA), and a co-author. "Of so, the disease necessitating the surgery, not so much the surgery itself, may be hurting memory.”