AT THE 2015 VASCULAR ANNUAL MEETING
CHICAGO (FRONTLINE MEDICAL NEWS) – Don’t automatically discontinue dual antiplatelet therapy for carotid endarterectomy because the neuroprotective effects may outweigh the bleeding risks, researchers concluded after a review of more than 28,000 patients who underwent the procedure during 2003-2014.
They found in the study that the 7,059 patients on perioperative dual antiplatelet therapy with clopidogrel (Plavix) and aspirin had about a 40% reduction in transient ischemic attacks (TIAs), strokes, and stroke-related deaths when compared with the 21,624 patients on aspirin alone.
The investigators found on multivariate analysis that bleeding bad enough for a return trip to the operating room was more common in their dual antiplatelet group (odds ratio, 1.73; P < .01), but they felt the neuroprotective effect was probably worth the “slightly increased bleeding risk.” Earlier research suggests that about half of vascular surgeons will discontinue clopidogrel a week or so before carotid endarterectomy (CEA) because of bleeding risks ( Eur. J. Vasc. Endovasc. Surg. 2009;38:402-7 ).
“Although dual therapy increases perioperative bleeding, it confers an overall benefit by reducing stroke and death. Patients taking dual therapy at the time of CEA should continue treatment preoperatively. This study also suggests that initiating dual therapy is beneficial for asymptomatic patients,” lead investigator Dr. Douglas Jones of the New York Presbyterian Hospital in New York said at the meeting hosted by the Society for Vascular Surgery.
The team used the Society for Vascular Surgery’s (SVS) Vascular Quality Initiative database. Patients were about 70 years old on average and about 60% were men. Dual-therapy patients had more coronary artery disease, congestive heart failure, chronic obstructive pulmonary disease, and diabetes.
On multivariate analysis to control for those differences, dual therapy was protective against TIA or stroke (OR, 0.60; P < .01); ipsilateral TIA or stroke (OR, 0.68; P = .05); stroke (OR, 0.62; P = .04); and stroke death (OR, 0.65; P = .03). It did not protect against myocardial infarction.
“More than 95% of patients received heparin for these cases,” said Dr. Jones, noting that protamine-reversal after the case “had the greatest protective effect” against major bleeding, which is consistent with previous reports. Protamine reversal reduced it by more than 50% (OR, 0.44; P < .01).
The results, for the most part, were similar on propensity matching of 4,548 patients on dual therapy to 4,548 on aspirin alone, all of whom had CEA after 2010. Dual-therapy patients were about twice as likely to return to the operating room for bleeding (1.3% vs. 0.7%), but also had fewer thrombotic complications (for instance, stroke 0.6% vs. 1.0% in the aspirin cohort).
Asymptomatic patients on dual therapy were again about twice as likely to return to surgery for major bleeding, but half as likely to have a stroke. Bleeding was more common in symptomatic dual therapy patients, as well, but for reasons that aren’t clear, a trend toward fewer thrombotic events in symptomatic patients on propensity matching did not reach statistical significance. “The protective effect was greatest among asymptomatic patients,” Dr. Jones said.
Patients on dual therapy were also more likely to have a drain placed, but drain placement did not protect against reoperation for bleeding (OR, 1.06; P = .75).
Dr. Jones has no disclosures. Other investigators disclosed consulting fees from Medtronic, Volcano, Bard, and AnGes.