Introduction: Postoperative paroxysmal atrial fibrillation (POPAF) is a frequent arrhythmic complication after cardiac surgery which delays hospital discharge. We have evaluated preoperative predictors of risk of POPAF in patients after ATS mechanical heart valve replacement.
Methods: We retrospectively analyzed the association of selected parameters and incidence of POPAF (within 7 days post surgery) in a total of 219 patients who underwent ATS mechanical heart valve replacement between 1997 and 2007 in a single institution. Out of 219 patients (mean age 61, 140 male and 79 female), 88% had aortic valve replacement and 12% had mitral valve replacement. All statistical analyses were performed using STATA 10.0 software with Fisher's exact test and a logistic regression analysis.
Results: POPAF occurred in 44 (20%) of the patients of which 62% were male and 38% were female. Following variables were identified as risk factors by univariate analyses: age .60; male>female; NYHA class .II; presence of pulmonary hypertension; obesity (BMI .30 kg/m2); left atrial enlargement, and concomitant coronary artery bypass graft surgery (CABG). Hypertension, diabetes mellitus type 2, hypercholesterolemia, chronic kidney disease, coronary artery disease, congestive heart failure, and smoking had non-significant impact (P>0.05). By multivariate logistic regression and after adjusting for other
variables, two variables were found to be statistically significant predictors: obesity (BMI .30 kg/m2) (OR 2.5; 95% CI 1.1 to 5.6; P=0.03) and presence of pulmonary hypertension (OR 8.49; 95% CI 3.52 to 19.65, P=0.001).
Conclusions: This study demonstrates that obesity (BMI .30 kg/ m2) and presence of pulmonary hypertension are independent risk factors for the occurrence of POPAF after heart valve replacement surgery. Identification of those patients and administration of prophylactic treatment might lead to prevention of this condition.