The long-term impact of postoperative atrial fibrillation after cardiac surgery

Abstract

Objective: The literature has reported worse in-hospital outcomes for patients with atrial fibrillation. The objective of the following study is to provide detailed results on the long-term impact of postoperative atrial fibrillation on survival and hospital readmission in cardiac surgery.

Methods: All patients undergoing open cardiac surgery were reviewed with the exclusion of preoperative atrial fibrillation or patients undergoing ventricular assist device, transplant, or Cox-Maze procedures. Propensity matching (1:1) was performed to ensure similar baseline characteristics. Multivariable analysis identified significant associations with mortality and readmission.

Results: A total of 12,227 patients with cardiac disease were divided into 7927 patients (64.8%) without postoperative atrial fibrillation and 4300 patients (35.2%) with new-onset postoperative atrial fibrillation. Propensity matching (1:1) yielded 4275 risk-adjusted pairs. There was no difference between the nonpostoperative atrial fibrillation versus postoperative atrial fibrillation cohorts regarding operative mortality (4.61% vs 4.12%; P = .26) and stroke (2.32% vs 2.76%; P = .191). Patients with postoperative atrial fibrillation had higher rates of reoperation (12.12% vs 6.83%; P < .001), transfusion (43.42% vs 36.94%; P < .001), sepsis (1.99% vs 0.80%; P < .001), prolonged ventilation (15.88% vs 9.24% vs; P < .001), pneumonia (6.60% vs 2.36%; P < .001), renal failure (6.90% vs 3.37%; P < .001), and dialysis (4.94% vs 2.08%; P < .001). The postoperative atrial fibrillation cohort had a significantly higher incidence of atrial fibrillation on follow-up (11.74% vs 4.75%; P < .001). Postoperative atrial fibrillation was independently associated with mortality (hazard ratio, 1.21; 1.12-1.33; P < .001), all-cause readmissions (hazard ratio, 1.05; 1.01-1.1; P = .010), and heart failure-specific readmission (hazard ratio, 1.14; 1.04-1.26; P = .01).

Conclusions: Patients in the postoperative atrial fibrillation cohort had worse perioperative morbidity, lower survival, and more readmissions for heart failure on long-term follow-up.

Keywords: atrial fibrillation; cardiac surgery; heart failure readmissions.