New-Onset Post-Operative Atrial Fibrillation in Patients Undergoing Coronary Artery Bypass Grafting Surgery - A Retrospective Case-Control Study

ABSTRACT Introduction: New-onset postoperative atrial fibrillation (POAF) is a common complication following coronary artery bypass grafting (CABG) surgery. Objective: To explore predictive factors and potential mechanisms of new-onset POAF in isolated off-pump CABG patients. Methods: Retrospective observational case-control study of 233 patients undergoing isolated off-pump CABG surgery between August 2018 and July 2020 at the Department of Thoracic and Cardiovascular Surgery, the Affiliated Drum Tower Hospital of Nanjing University Medical School. Associations between predictor variables and new-onset POAF were identified. The main outcome was new-onset POAF after CABG surgery. Results: A total of 75 (32.19%) patients developed new-onset POAF after CABG surgery. The new-onset POAF patients had advanced age, higher baseline systolic blood pressure, more preoperative use of diuretic drug, more transfusion of blood products, atrial dilation and postoperative positive inotropic drug treatment. Nineteen variates entered the multivariable logistic regression model with a Hosmer-Lemeshow test score of 7.565 (P=0.477). Postoperative left atrial enlargement, postoperative drainage in the first 24 hours and total length of hospital stay were statistically significant, while postoperative right atrial enlargement (OR and 95% CI, 7.797 [0.200, 304.294], P=0.272) and left atrial enlargement (3.524 [1.141, 10.886], P=0.029) assessed by echocardiography had the largest OR value. Conclusion: Atrial enlargement is strongly associated with new-onset POAF in patients with isolated off-pump CABG, thus it highlights the advantage of echocardiography as a useful tool for predicting new-onset POAF. Careful monitoring and timely intervention should be considered for these patients.

摘要
引言：术后新发心房颤动（postoperative atrial fibrillation, POAF）是冠状动脉旁路移植术（coronary artery bypass grafting, CABG）后常见的并发症。
目的：探讨单纯非体外循环冠状动脉旁路移植术患者术后新发POAF的预测因素及潜在发病机制。
方法：本研究为回顾性观察性病例对照研究，纳入2018年8月至2020年7月期间南京大学医学院附属鼓楼医院胸心血管外科收治的233例行单纯非体外循环CABG的患者，分析预测变量与术后新发POAF的关联，主要结局指标为CABG术后新发POAF。
结果：共计75例（32.19%）患者在CABG术后发生新发POAF。新发POAF患者年龄更高、基础收缩压水平更高，术前利尿剂使用比例更高，血液制品输注量更多，心房扩张程度更显著，且术后接受正性肌力药物治疗的比例更高。共19个变量进入多因素logistic回归模型，Hosmer-Lemeshow检验得分为7.565（P=0.477）。术后左心房扩大、术后前24小时引流量及总住院时长具有统计学意义；而经超声心动图（echocardiography）评估的术后右心房扩大[比值比（odds ratio, OR）及95%置信区间（95% confidence interval, 95%CI）：7.797（0.200, 304.294），P=0.272]与左心房扩大[3.524（1.141, 10.886），P=0.029]具有最大的OR值。
结论：单纯非体外循环冠状动脉旁路移植术患者的心房扩大与术后新发POAF密切相关，这凸显了超声心动图作为预测术后新发POAF的有效工具的优势。对于此类患者，应予以严密监测并及时采取干预措施。