When I had my heart attack several years ago, I never thought for one moment that I'd ever need a bypass.
Last Aug. 2005, that all changed - I had a triple bypass. I also had a mild stroke. Strokes happen in '1-5% of bypass patients'.
I found myself sort of drifting mentally and not quite as sharp as I had been. This is known as "short term deficits and these are primarily problems with memory, attention and concentration, and can occur in 33 percent to 83 percent of patients. They generally improve over time."
With the passage of these last 12 months, I've found that some of the mental acuity has returned, but at times a bit of forgetfulness remains. 
So if you've ever had a bypass, tell your story here and let me know how it affected you!
I also found the following article that explains alot of this...
Hugs always, Teri 
http://www.clevelandclinic.org/health/health-info/docs/3000/3046.asp?index=10731