NEW YORK – Considerable controversy surrounds the use of the anticoagulant clopidogrel in patients before, during, and after surgery for peripheral artery disease, but in a study of more than 10,000 patients, rates of postoperative bleeding complications were similar between those who continued the drugs before surgery and those who did not.
Dr. David H. Stone presented the results of the study, which involved 10,406 patients and 12 centers from the Vascular Study Group of New England, at the annual meeting of the Eastern Vascular Society. Four previously published single-center studies of the use of clopidogrel (Plavix, Bristol-Myers Squibb/Sanofi Pharmaceuticals Partnership) in vascular surgery patients accounted for fewer than 200 patients, he noted.
The patients in the New England study had carotid endarterectomy (CEA), lower extremity bypass, or endovascular or open abdominal aortic aneurysm (AAA) repair over a 6-year period. The study looked at reoperation for bleeding across all procedures and at blood transfusions in all procedures except CEA. Across all measures, the variations between the clopidogrel and non-clopidogrel groups were not statistically significant, said Dr. Stone of the Dartmouth-Hitchcock Medical Center in Lebanon, N.H.
The largest variations were seen in the blood transfusion rates in endovascular AAA repair (16% in the clopidogrel group vs. 11% in the non-clopidogrel group), and in open AAA repair (43% vs. 38%, respectively).
The rates of reoperation for rebleeding, however, were almost identical in CEA, lower extremity bypass, and endovascular AAA repair. In open AAA repair, the clopidogrel group actually had a lower rate than did the non-clopidogrel group (1.6% vs. 2.4%). “Based on our sample size, these conclusions are most robust for carotid endarterectomy and open AAA repair,” Dr. Stone said.
Dr. John J. Ricotta of Washington (D.C.) Hospital Center questioned the strength of using the blood transfusion rate as an outcome measure, because standards for using transfusion can vary among centers. “With the exception of open aneurysm repair, you picked operations that are relevant but are not highly associated with bleeding problems,” he said.
“I would agree with that analysis, but surprisingly in our own region and apparently in Europe the majority of surgeons – just looking at carotid endarterectomy – still hold Plavix prior to surgery for obviously a perception of increased bleeding,” Dr. Stone said.
In lower extremity bypass, Dr. Ricotta said, more precise predictors of bleeding problems are reoperation, obesity, and long incisions. “Did you look at these variables?” he asked.
Dr. Stone said that the study did not include an analysis of body mass index specifically, but that the pending CASPAR (Clopidogrel and Acetyl Salicylic Acid in Bypass Surgery for Peripheral Arterial Disease) trial would show no disparity between groups undergoing lower extremity bypass.
“Based on our analysis of over 10,000 patients, perioperative antiplatelet regimens, including Plavix, appear safe among those undergoing commonly performed vascular operations,” Dr. Stone said. “Accordingly, we believe that Plavix can be safely continued in patients with important indications for its use, such as symptomatic carotid disease or recent drug-eluting cardiac stent placement.”
Dr. Stone said that he had no relationships to disclose.