Aspirin alone proved as effective as aspirin plus the blood clot preventer Plavix in keeping coronary artery bypass grafts open during the first year after surgery, according to a study released on Monday.

The study was designed to see if the addition of Plavix -- already a $9 billion a year seller for Bristol-Myers Squibb Co and Sanofi Aventis -- to standard aspirin therapy would help further reduce vein narrowing or blockages after coronary artery bypass surgery.

We found no significant difference in the amount of vein graft thickening, or the number of blocked bypasses, cardiovascular events or bleeding events in the 113 surgery patients treated with either aspirin and clopidogrel (Plavix) or aspirin alone, said Dr Alexander Kulik, a cardiovascular surgeon who led the study.

The data were presented at the American Heart Association scientific meeting in Orlando.

The success rate after one year was 93.2 percent for aspirin alone and 94.3 percent for patients on aspirin plus Plavix, a difference not considered to be statistically significant.

More than 90 percent of patients in the trial were also taking cholesterol lowering statins -- standard therapy for heart patients.

While the duel clot-preventing therapy of aspirin and Plavix is standard during and after artery-clearing angioplasty procedures, some surgeons have begun using the combination after bypass surgery in the belief that it might improve outcomes, Kulik explained.

This study failed to validate that theory, Kulik said.

The good news is that patients and their doctors can expect more than 90 percent of vein grafts to remain open one year after surgery with the use of aspirin and statins, he said.

Medicine