Their conclusions reflect a major shift from the notion that bad cholesterol, or LDL, is the primary villain in heart disease. Levels of C-reactive protein also must be reduced to halt the disease's progression, researchers said.

In that simple assertion lies the seed of a major debate among heart specialists. Revised last year, current treatment guidelines reflect what studies then showed: the importance of lowering LDL to below 70 milligrams per deciliter of blood in high-risk patients.

But most doctors don't track CRP as they do cholesterol or prescribe drugs, such as Lipitor and other potent statins, to reduce it. If doctors are to provide quality care, the researchers said, that will have to change. The inexpensive CRP test ($10 to $15) is widely available and can be done as part of other blood tests.

"If we think only about cholesterol, we now have hard evidence that we're not doing the best we can for our patients," said the lead author of one of the papers, Paul Ridker of Brigham and Women's Hospital in Boston.