There was no significant difference between early and delayed invasive strategy for preventing death, heart attack or stroke.
But in a subgroup at highest risk (those with more severe heart attack), earlier was better for preventing death, heart attack or stroke.
There were no major differences in major bleeding or other safety concerns between the two groups.
"This is the major interventional cardiology trial being presented at AHA. It is also the largest trial on this topic, and the largest trial there has ever been on this topic," Bhatt said. "It is immediately relevant to patients, to doctors, and to the health-care system.
A second study found that an experimental oral clot-busting drug, rivaroxaban, was safe and resulted in a 6 percent absolute risk reduction for death, heart attack or stroke in patients with acute coronary syndrome (heart attack or unstable angina).
The study was the first to look at the effects of the drug in the arteries.
Existing drugs target the platelets in the bloodstream. Rivaroxaban targets a different part of the clotting process, called Factor X, said principal investigator Dr. Michael Gibson, chief of clinical research in cardiovascular disease at Beth Israel Deaconess Medical Center in Boston.
The American Heart Association has more on acute coronary syndrome.
SOURCES: Nov. 10, 2008, news conference with Deepak Bhatt, M.D., Brigham and Women's Hospital, Boston; Shamir Mehta, M.D., directo
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