POAF linked to increased risk for death following CABG
MedWire News: Patients who undergo coronary artery bypass graft (CABG) surgery have an increased risk for death if they experience postoperative atrial fibrillation (POAF), suggest study findings that also showstatin therapy improved survival in this group of patients.
Although POAF appears to be a benign complication for the majority of patients, the present study confirms that it is a strong independent predictor for both operative and late mortality.
"Patients who develop POAF should be considered at higher risk for adverse outcomes in the short and long-term. Closer follow-up and aggressive secondary prevention programs (lifestyle modification, pharmacotherapy) might thus be applied in these high-risk patients," say Patrick Mathieu (Laval Hospital, Quebec, Canada) and co-authors.
For the study, the researchers retrospectively assessed preoperative and operative data on 6728 patients who underwent a first isolated CABG procedure. None of the patients had a preoperative history of paroxysmal or chronic AF.
In total, 27.8% of patients experienced POAF and the overall operative mortality rate - defined as death from any cause in the 30 days following CABG - was 1.3%. Over an average 2.8-year follow-up, 321 patients died.
Compared with patients who did not experience POAF, those who did had significantly increased operative mortality (0.9 vs 2.3%), postoperative renal failure (4.7 vs 12.5%), and stroke (1.2 vs 2.6%). Indeed, multivariate analysis showed that patients with POAF were 78% more likely to experience intraoperative death than those without.
Long-term analysis showed that POAF remained a significant predictor for long-term mortality (hazard ratio [HR]=1.35), even after adjusting for perioperative complications such myocardial infarction, renal failure, and stroke.
Further analysis showed that when deaths occurring within the first year following surgery were excluded, the survival rate decreased significantly. After adjusting for other risk factors, POAF was independently associated with long-term mortality beyond 1 year (HR=1.6).
Statin treatment was found to confer a significant protective effect in POAF patients for both operative mortality (odds ratio [OR]=0.38) and long-term mortality (HR=0.62), whereas it provided no benefit to patients without POAF. Indeed, POAF patients who received statins had a significantly lower mortality rate than those who did not, at 1.6% versus 5.1%.
"Unless contraindicated for adverse side effects, statins should be prescribed in every patient undergoing CABG," conclude Mathieu and team in Clinical Cardiology.
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By Ingrid Grasmo