Post-operative atrial fibrillation during cardiac rehabilitation: incidence and long-term prognostic value

Abstract Background Postoperative atrial fibrillation (POAF) represents a common complication after cardiac surgery and is associated with longer in-hospital stay and increased in-hospital death and stroke, but its long-term prognostic value, during cardiac rehabilitation (CR), remains not well understood. Purpose The study aimed to assess the incidence and long-term prognostic values of different types of POAF in a cohort of consecutive patients who undergo CR after cardiac surgery. Methods A consecutive registry of patients admitted to our CR after cardiac surgery represents the present study. POAF was defined as any episode of atrial fibrillation occurring in the post-operative period from post-intensive care unit to hospital discharge after CR; moreover, POAF types were classified as Paroxysmal POAF (early and late) and persistent (early and late). Long-term hard end-points were: cardiovascular (CV) mortality and major adverse cardiovascular and cerebrovascular events (MACCEs defined as a composite of cardiovascular death, heart failure hospitalization, non-fatal myocardial infarction, and stroke). Results A total of 2.020 patients were included, mean age was 67 years and male gender was prevalent (71%). CR post-coronary artery bypass graft (CABG) was the indication of CR in 53% of patients, cardiac valve surgery in 35%, while 11% underwent CR after CABG plus valve surgery. All patients were followed for a mean of 50 months. POAF was found in 392 patients (19.4%) divided into 36% paroxysmal POAF and 64% persistent POAF, while 7.7% had permanent atrial fibrillation (figure 1A). Overall POAF was associated with higher rates of CV death (SR 5.0% vs POAF 7.2% vs pAF 16.5%; p<0.001) and MACCEs (SR 12.4% vs POAF 19.6% vs pAF 25.2%; p<0.001 – figure 1B). By analyzing separately paroxysmal, persistent, early, and late POAF, interestingly only late POAF (both persistent or paroxysmal) was associated with a higher long-term CV risk, in particular, both late persistent and late paroxysmal were associated with a higher risk of MACCEs (late persistent: OR 1.65, p=0.004 / late paroxysmal: OR 1.98, p=0.002 – figure 1C), mainly driven by a higher rate of heart failure hospitalization. Interestingly late paroxysmal POAF showed the worst outcomes among all classified POAF (figure 1D). Conclusions POAF after cardiac surgery is associated with long-term adverse outcomes, but not all POAF have the same prognostic value. Late, rather than early, POAF (whether paroxysmal or persistent) is associated with a poor long-term prognosis after cardiac rehabilitation.Figure 1