Long term risk of recurrent atrial fibrillation and ischemic stroke after post-operative atrial fibrillation complicating cardiac and non-cardiac surgeries

Background: New onset post-operative atrial fibrillation (POAF) can complicate both non-cardiac(NCS) and cardiac(CS) surgeries. Long term differences in recurrence of atrial fibrillation (AF) and incidence of ischemic stroke/transient ischemic attack(CVA)between these types of POAFare lacking. Objective: To compare thelong term recurrence rate of AF and incidence of CVAin patients withnew onset POAF after CS and NCS. Methods:All patients who developed POAF between May 2010 and April 2014 were included in this single-center, retrospective study Exclusion criteria included a prior history of atrial tachyarrhythmias and pre-operative use of anti-arrhythmic drugs. Recurrence of atrial fibrillation and CVA was identified by review of medical records,electrocardiogram and Holter monitor. Results: patients identified by the ICD9 code=523, 112 patients (61 cardiac; 51 non-cardiac) met inclusion criteria. Mean follow up was 943 days (range 32-2052 days).AF recurrence rate within 30 days after hospital discharge was higher in CS compared with NCS(10% vs 0%, p =0.03). Kaplan Meier analysis showed a trend towards higher recurrence in NCS compared with CS(HR 2.8; 95% CI 0.78-10.6, log rank p =0.03). In long term follow-up, CVA was numerically more common in patients with POAF after CS compared with NCS(10% vs 2%) though this difference was non-significant(HR 3.1; 95% CI 0.72-13.3; log rank p =0.26). Conclusions: The risk of recurrent AF and ischemic stroke is not different between POAF after CS or NCS. The overall high rate of AF recurrence and risk of ischemic stroke mandate careful long term follow-up.