Po-01-020 peri-operative amiodarone prophylaxis in cardiovascular surgery: impacts on post-operative length of stay according to procedure types

Post-operative Atrial Fibrillation (POAF), occurring in nearly 20-50 percent of cardiovascular surgery (CVS) patients, is associated with prolonged hospitalization and excess costs of care. Peri-operative Amiodarone prophylaxis has been an effective strategy to reduce the incidence of POAF. A retrospective evaluation of the impact of Amiodarone prophylaxis on post-operative length of hospital (LOS) stay, according to CVS procedure types. Hospitalization information was available for 2704 consecutive CVS patients at a single tertiary care centre (2013-2016). CVS included standalone, or combined procedures that involved: valvular heart surgery (VHS), coronary artery bypass graft (CABG), and other miscellaneous procedures (e.g. ascending aorta replacement, endarterectomy). Hierarchical linear regression was used to evaluate the impact of Amiodarone prophylaxis on LOS, adjusted for demographic and clinical characteristics. Among the 2704 patients, there were 866 (32.0%) cases of POAF. LOS, was significantly longer in patients with POAF (+2.78 days, p<0.001). LOS was 1.62 days shorter in patients who received Amiodarone prophylaxis (p=0.007). Within all operative categories, LOS was shorter in patients receiving amiodarone prophylaxis, though statistical significance was only observed in VHS (including VHS + other) and VHS + CABG procedure types. Specifically, Amiodarone prophylaxis was associated with shorter LOS among: patients who had CABG but not VHS (8.26 versus 9.45 days, p= 0.29), patients who had VHS but not CABG (7.62 versus 11.02 days, p<0.001), patients undergoing VHS + CABG (9.36 vs. 12.41 days, p<0.03), and patients undergoing VHS + CABG + other (13.54 versus 15.09 days, p= 0.74). After adjusting for demographic-clinical covariates in a hierarchical multiple regression, Amiodarone prophylaxis remained an independent predictor of shorter LOS (b= -2.3 [-3.7, -0.93], p= 0.001). Other independent predictors included: left atrial diameter of >40 mm (b= 1.7 [0.90, 2.85], p< 0.001), female sex (b= 1.4 [0.56, 2.19], p= 0.001), history of heart failure (b= 2.1 [0.94, 3.30], p< 0.001), and CVS involving VHS + CABG (b= 1.4 [0.15, 2.67], p= 0.03), and VHS + CABG + other (b= 5.1 [2.51, 7.72], p<0.001). Amiodarone prophylaxis is independently associated with significantly shorter LOS following CVS.