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When to Stop Aspirin Before CABG-Plus-Valve Surgery?

By Will Boggs MD
NEW YORK (Reuters Health) Jan 26 - The risk of bleeding after combined coronary artery bypass graft (CABG) and valve surgery is higher when chronic aspirin therapy is stopped within five days of the operation, compared to when it's stopped at least six days in advance.
The finding is from a review of such surgeries done at the Cleveland Clinic in Ohio, reported by Dr. Leslie Cho and colleagues.
Dr. Cho told Reuters Health by email that surgeons need to weigh the risk of bleeding vs. the benefit of aspirin before combined CABG/valve surgery.
"For example, if the patient has a drug-eluting stent and needs surgery, continuing aspirin makes sense,' Dr. Cho said. "However, if the patient is at high risk of bleeding" - because of anemia or older age, or because the surgery is a redo, for example - "then holding aspirin makes sense."
The data, from 1,963 patients on chronic aspirin therapy who underwent nonemergent CABG/valve surgery, were published online December 22 in the American Journal of Cardiology.
When patients were matched based on propensity scores, there was no difference between early and late aspirin discontinuation groups (i.e., within five days or at least six days pre-op) in the primary endpoint, a composite of in-hospital mortality, myocardial infarction, and stroke.
However, significantly more patients in the late-use group received postoperative transfusions (49% vs 42%, p=0.02), and there was a trend toward more reoperations for bleeding in the late-use group (6.1% vs 3.7%; p=0.08).
Guidelines from the Society of Thoracic Surgeons recommend that aspirin be stopped three to five days before elective CABG, whereas American College of Cardiology/American Heart Association guidelines suggest stopping 7 to 10 days in advance. Neither set of guidelines specifically addresses the issue of patients having combined CABG and valve surgery, the researchers note.
"For many years, surgeons and cardiologist had no real sense of when to stop aspirin," Dr. Cho said. "I hope with our study, they can make a logical decision about when to stop aspirin."
To better define patients' risk, Dr. Cho added, "We are currently planning to do a study looking at the level of aspirin function (arachidonic acid light transmittance aggregometry study) as relates to bleeding outcome."
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