Post-operative atrial fibrillation (POAF) is a frequent complication occurring in 30% to 50% of patients after cardiac surgery. It is associated with an increased risk of mortality and morbidity, predisposes patients to a higher risk of stroke, requires additional treatment, and increases the costs of the post-operative care. The aim of this review is to present the current state of knowledge about the risk factors, mechanisms, prevention, and treatment of this complication. In addition to the well known risk factors for the development of POAF such as age, left atrial enlargement, and valvular surgery, new metabolic risk factors related to visceral obesity have been identified. With regard to the prevention of POAF, beta-blocker drugs are effective and safe and can be used in most patients, whereas amiodarone can be added in high-risk patients. Biatrial pacing was shown to be effective; however, its complexity might limit its application. Although there are only few data regarding the usefulness of magnesium, statins, N-3 polyunsaturated fatty acids, and corticosteroids, their addition to beta-blocker drugs might be of benefit for further reducing POAF. Treatment includes the use of an AV nodal blocking agent to achieve the rate control. If AF does not spontaneously convert to sinus rhythm within 24 h, anticoagulation should be initiated and a rhythm control strategy should be attempted. More investigations are warranted to explore mechanisms by which POAF occurs. This new knowledge would undoubtedly translate into a more efficient prevention and treatment of this common post-operative complication that is associated with a major health and economic burden.

PET/CT is useful in differentiating between CIED infection and recent post-implant changes. It may guide appropriate therapy.

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Background-Postoperative atrial fibrillation (POAF) is a highly prevalent complication after cardiac surgery with substantial effects on outcomes. Previous studies have reported that obesity is a risk factor for POAF after cardiac surgery. However, it is unknown whether the metabolic syndrome (MS) also increases the risk of postoperative atrial fibrillation. Methods and Results-We retrospectively analyzed the association between obesity and MS and the incidence of new-onset POAF in a total of 5085 patients who underwent isolated coronary artery bypass grafting surgery with no concomitant valvular surgery. Of these patients, 1468 (29%) were obese (body mass index Ն30 kg/m 2 ) and 2320 (46%) had a MS as defined by the NCEP-ATPIII. POAF occurred in 1374 (27%) of the patients. Obesity was associated (PϽ0.001) with increased incidence of POAF in the whole cohort as well as in patients Ͼ50 years old but not in patients Յ50 years old. In these patients, MS was the only metabolic factor to be significantly associated with higher incidence of POAF (12% versus 6%, Pϭ0.01). In Ͼ50-year-old patients, mild (30 Յ body mass index Ͻ35 kg/m 2 ) and moderate-severe (body mass index Ն35 kg/m 2 ) obesity were independently associated with a 1.4-fold (95% CI: 1.10 to 1.71; Pϭ0.004) and 2.3-fold (95% CI: 1.71 to 3.13; PϽ0.0001) increase in the risk of POAF, respectively. In Յ50-year-old patients, MS (relative risk [RR]: 2.36; 95% CI: 1.10 to 5.12; Pϭ0.02) but not obesity was independently associated with POAF. Conclusion-This study demonstrates that obesity is a powerful risk factor for the occurrence of POAF after isolated coronary artery bypass grafting surgery in patients older than 50 years. However, in the younger population, this association is not observed and MS is the only metabolic risk factor to be independently associated with POAF.

Patients with increased WC combined with elevated C-reactive protein levels are at higher risk for POAF. Thus, interventions targeting inflammation related to visceral obesity might help reducing the incidence of POAF.