Antiplatelet therapy before saphenous vein graft surgery produces better outcomes

January 29, 2013 – Ralf Harskamp, MD, was first author of a new study that analyzed how patients responded to different therapies before undergoing a coronary artery bypass graft.

Antiplatelet therapy before saphenous vein graft (SVG) surgery is associated with a lower risk of adverse cardiac events, according to a new study by the DCRI’s Ralf Harskamp, MD, and Renato Lopes, MD, PhD, and colleagues from the University of Amsterdam.

The study appears in the January 15 issue of The American Journal of Cardiology.

SVG surgery is a procedure in which surgeons remove part of the saphenous vein (which runs through the lower leg and thigh) to repair damaged blood vessels, as in a coronary artery bypass graft (CABG). Current guidelines for SVG and CABG recommend the use of antiplatelet therapy after the procedure to improve the odds of success. Nonetheless, SVG failure occurs in half of all CABG patients. SVG procedures are also associated with worse outcomes than native-vessel percutaneous coronary intervention (PCI). Recent efforts to improve outcomes have met with mixed results. Harskamp, Lopes, and their colleagues attempted to determine whether the use of antiplatelet therapy before SVG could produce better outcomes.

To do so, the researchers obtained data on patients who underwent SVG intervention at the University of Amsterdam between 2003 and 2008. Patients were divided into three groups: those who received no antiplatelet therapy prior to hospital admission, those who received aspirin or clopidogrel before admission, and those who received dual antiplatelet therapy (aspirin and another antiplatelet drug) before admission. Clinical follow-up examinations were performed at 30 days and 1 year.

Of the 225 patients who underwent SVG intervention, 87 percent were men, and the mean age was 70 years. Twenty-one patients (9.4 percent) were not receiving antiplatelet therapy, 102 (45.3 percent) were receiving aspirin or clopidogrel, and 102 (45.3 percent) were receiving dual antiplatelet therapy. Incidence of death, heart attack, revascularization, and stroke was greater at 30 days in patients without preadmission antiplatelet use (38.1 percent) than in patients who received aspirin or clopidogrel (14.9 percent) or those who received dual antiplatelet therapy (13.9 percent). Similar findings were found at 1 year (52.4 percent, 29.5 percent, and 28.3 percent, respectively). Dual antiplatelet therapy, the researchers concluded, was not superior to single antiplatelet therapy in producing better patient outcomes.

Although the study’s findings suggest that antiplatelet therapy prior to hospitalization can produce better outcomes for SVG patients, the researchers cautioned that this strategy has limitations. Many CABG patients are resistant to aspirin, for example. Further research into the efficacy and safety of antiplatelet agents is needed, the authors said.