麻豆传媒

New-onset atrial fibrillation (Afib), is more common after coronary artery bypass grafting (CABG) than after stenting for left main disease, and undoes the outcome equivalence of the two procedures when it occurs, according to a post hoc analysis of the EXCEL trial.

Among the trial's low-to-intermediate-risk patients, 18.0% randomized to CABG developed new-onset Afib compared with 0.1% after percutaneous coronary intervention (PCI) at a mean 2.7 days after the procedure (P<0.0001), the study in the Feb. 20 issue of the showed.

When patients developed new-onset Afib, they stayed longer in the hospital, were more likely to be discharged on anticoagulant therapy, and had higher odds of major and minor bleeding by 30 days, noted investigators Gregg Stone, MD, of New York-Presbyterian/Columbia University Medical Center in New York City, and colleagues.

The main finding of EXCEL, that stenting was on par with surgery, was previously reported at the Transcatheter Cardiovascular Therapeutics meeting in 2017. The new analysis included 1,812 patients without Afib at baseline.

Three years after CABG, patients who acquired new-onset Afib were often worse off compared with peers with no Afib:

• Stroke (6.6% versus 2.4%, adjusted HR 4.19, 95% CI 1.74-10.11)
• Death (11.4% versus 4.3%, adjusted HR 3.02, 95% CI 1.60-5.70)
• Combined death, MI, stroke (22.6% versus 12.8%, adjusted HR 2.13, 95% CI 1.39-3.25)

"Notably, new-onset Afib was a stronger multivariable predictor of death after CABG than either diabetes or reduced LVEF [left ventricular ejection fraction]," Stone's group said.

"PCI had superior 3-year event-free survival compared with CABG if new-onset Afib after surgery occurred. PCI may thus be preferred in selected patients who have a very high risk of new-onset Afib after surgery," they added.

Advanced age, increased BMI, and reduced LVEF independently predicted onset after CABG in the trial but with modest C-statistics. The researchers noted that "many patients who may benefit from CABG have these characteristics."

They suggested that "rather than avoiding CABG in these patients, effective pre-operative and perioperative measures (prophylactic beta-blockers or amiodarone) should be considered to prevent the post-surgical occurrence of new-onset Afib."

New-onset Afib was resolved by hospital discharge 85.8% of the time.

"If post-operative Afib persists post-hospitalization, then most if not all of these patients at high risk of stroke would warrant long-term oral anticoagulation," according to an editorial comment by Atul Verma, MD, Southlake Regional Health Centre in Ontario, and colleagues.

"If we believe that post-operative Afib may continue well beyond hospitalization and lead to long-term morbidity and mortality, as suggested by the current EXCEL analysis, then randomized trials on the benefits of oral anticoagulation in this population must be undertaken," the editorialists suggested.