Apparently from the surgery:
"Brain damage during bypass surgery is so common that hospital personnel refer to it as “pump head.” The primary cause is emboli produced during surgery from clamping the aorta and from the “heart-lung machine.” This machine pumps blood to keep the patient alive while the heart is stopped during the operation. Unfortunately, this pump also introduces toxic gases, fat globules, and bits of plastic debris into the bloodstream of the patient under anesthesia. Once they are in the bloodstream, these particles migrate to the brain where they can clog capillaries and prevent adequate amounts of blood and oxygen from flowing to the brain. Essentially, all patients experience brain emboli during surgery and for many the damage is permanent." http://www.drmcdougall.com/misc/2008other/080412clinton.htm
You may want to read Dr. Caldwell Esselstyn's book, 'Prevent and Reverse Heart Disease,' if this topic interests you. Esselstyn has some videos on YouTube as well. He has been treating people (in Cleveland, OH) dying from heart disease for almost 20 years on a low fat vegetarian diet, enabling them to avoid surgery. It's amazing work, along the line of Dean Ornish's plan. Sadly, many people would rather go thru a bypass than change their eating habits. Even sadder, if they don't change their eating habits after the first bypass, they are almost certainly going to have to have another one.
We always laugh about it, but it’s not really funny. There was an episode in “Home Improvement” where a guy is wanting to eat a pork sandwich; he keeps saying his doctor told him not to eat stuff like that. Finally, he yells, “Why’d I have that bypass surgery anyway?” as he stuffs down the sandwich.
So we have been saying “Why’d I have that bypass surgery anyway?” for several years now whenever we were making a joke about deliberately doing something health-wise that maybe was a little over the top, all things considered.
I guess the laughs we got out of that one may have been good for the heart, however!!