Subacute post-operative atrial fibrillation after valvular surgery in patients undergoing cardiac rehabilitation: predictive factors

Abstract Background Postoperative atrial fibrillation (POAF) is the most frequent arrhythmic complication following cardiac surgery (occurring in up to one third of patients). It may develop between the second and fourth postoperative days (acute POAF) as well as later, within 30 days after surgery (subacute). Episodes of atrial fibrillation in the subacute phase (sPOAF) are associated with an increase in morbidity, length of hospital stay and several complications both in the mid- and long- term. Therefore, POAF is not just an acute event but it may impact on long term clinical outcomes. Aim of the study The aim of this study was to identify the clinical predictors of postoperative atrial fibrillation in the subacute phase (sPOAF) in patients performing Cardiovascular Rehabilitation (CR) after cardiac surgery. Materials and methods A retrospective study was conducted on 737 post-surgical valvular patients (median age 62 years; 55,4% male) hospitalised in our Unit for in-patient CR program. During all the hospital stay patients received continuous monitoring with 12-lead ECG telemetry. We evaluated the predictive value of anamnestic data, the type of cardiac surgery intervention, the clinical course in the Cardiac Surgery Unit and in the CR Unit, the 6 minutes-walking tests (6MWT) parameters and main blood tests on sPOAF onset. Results SPOAF was documented in 170 patients (23,1%). Those who developed sPOAF were older [median 66 (56–74) years vs median 61 (50–70) years; p