• When to discontinue therapy prior to surgery is a physician’s judgment call.

By TCT Daily Staff

How long to continue dual antiplatelet therapy after stenting and how to handle such therapy when a patient needs surgery are two important and contentious issues in the field, said George Dangas, MD, PhD, of Columbia University Medical Center, New York, during an interview with TCT TV.

"We all know the importance of dual antiplatelet therapy, especially in unstable patients or patients with complicated disease," said Dangas, who added that there are early and late benefits in preventing thrombosis with such therapy.
Dangas said he recommends that all stent recipients take thienopyridines for at least a year, whether they received DES or bare-metal stents. "The one-year time frame, as a minimum, has been floating around for a while," he said. He maintains patients on dual antiplatelet therapy for up to five years if they are at high risk for late events.

Aspirin dosage

Geographic differences prevail regarding aspirin dosages in the dual-therapy regimen, Dangas said. Europeans tend to use 100 mg for the first month post-stenting, Canadians and Australians tend to prescribe 60 mg, and American interventional cardiologists often prescribe up to 325 mg.

Dangas said these differences are moving toward a consensus that doses higher than 81 mg are generally unnecessary. "Anything above baby aspirin was about the same for efficacy, but baby aspirin was much better for safety," he said. In his practice, Dangas now prescribes 81 mg for most patients. A few patients still receive 325 mg, although "there aren’t a lot of data to support" that dosage, he said.

Prior to surgery

When stent patients on dual antiplatelet therapy need a surgical procedure, Dangas said the patient’s cardiologist, internist, and surgeon "should all be involved in the decision on how to discontinue dual antiplatelet therapy. They should consider the particulars of the case when balancing risk of ischemic events vs. risk of bleeding during or after the procedure."

Biopsies probably present little risk, as do colonoscopies, but major cancer surgeries pose more risk, Dangas said. Also, a patient with a single stent will have lower risk than a patient with "six stents in three bifurcations," he said.

Surgeons, of course, want to minimize bleeding, but they also want to minimize ischemic risks, especially if such risks are explained to them, Dangas said.

In most cases, Dangas said he recommends discontinuing dual antiplatelet therapy for three to five days before surgery, depending on the details of the case. He exercises caution before restarting therapy within a day or two after surgery. This minimizes risk of ischemic events, he said.

Dangas said he typically tapers up to a full dose of thienopyridines after surgery, but if he is particularly concerned about a patient – for example, a patient with multiple stents – he recommends reloading with the full dose immediately.