I have not read the paper, but be aware that it refers to bypass for congestive heart failure, not for typical coronary disease (angina, heart attacks, severe big artery blockage being the usual symptoms and reasons for coronary artery bypass grafts).
Diffusely clogged arteries can cause heart failure but is a much smaller group than those having bypass for typical coronary disease. Many were not convinced that it was useful in the CHF group, and the study you describe seems to support that point of view.
San Francisco Area
ESR'd March 2010. FIRE'd January 2011.
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