A recent article in the Washington Post states that “the exact links among heart disease, bypass surgery and mood are unknown. One of the few certainties is that depression after surgery is more common in people who had previous episodes of the disorder.”

The article goes on to state that many experts believe that alterations to the normal circulation and blood pressure during bypass surgery, or small clots that form during the operation, may temporarily damage the brain, causing the depressive state.



Others adamantly believe that a patient’s first serious brush with death is what most likely causes them to develop depression.  Patients become alarmed at the need to take medicines when, previously, their lives may have been medication-free.  Everyday enjoyments may now be on their list of taboo things, such as involvement in sporting activities or other activities that may affect their heart. 

The disruptions caused even by successful treatment "in and of themselves can have significant effects on the way a person thinks, remembers, feels and acts," notes Roy Ziegelstein of Johns Hopkins University Medical Center. 

Other studies show that heart disease in late middle age may actually cause a decline in mental function.  The article in the Post notes a study by researchers at Duke University Hospital, published in 2001, which described the experience of about 250 coronary bypass patients who underwent "neuro-cognitive" testing before their operations and at intervals afterward.

At the time of discharge from the hospital, 53 percent showed a decline in thinking ability. At six weeks, that number was down to 36 percent, and at six months it was 24 percent, the study showed. But five years later, it was up to 45 percent.

Research also indicates that bypass surgery may cause subtle brain damage though more studies must be conducted to substantiate this.