Postoperative Atrial Fibrillation is Associated with Inflammatory Factors in the Pericardial Space

Objective: The specific mechanisms of postoperative atrial fibrillation (POAF) after cardiac surgery are unknown, but prior work in our laboratory suggested that atrial inflammation may play an important role. This study... [ view full abstract ]

Objective: The specific mechanisms of postoperative atrial fibrillation (POAF) after cardiac surgery are unknown, but prior work in our laboratory suggested that atrial inflammation may play an important role. This study investigated the relationship between POAF and inflammatory factors in the postoperative pericardial fluid.

Methods: Thirty patients undergoing CABG and/or valve surgery were enrolled. Exclusion criteria included history of atrial tachyarrhythmia, antiarrhythmic medications, and reoperative or emergent cardiac surgery. Pericardial fluid samples were collected upon pericardiotomy and at 4, 12, 24, and 48 hr postoperatively. AF was defined as atrial fibrillation or flutter of at least 30 sec duration on continuous telemetry monitoring. Multiplex bead-based immunoassays were performed for 52 inflammatory markers, and levels of each protein were compared between patients with and without POAF by multivariate, stepwise logistic regression analysis.

Results: The incidence of POAF was 43.3% (13/30). On univariate analysis, seven inflammatory factors were associated with POAF, including myoglobin, soluble vascular cell adhesion molecule 1 (sVCAM-1), soluble intercellular cell adhesion molecule 1 (sICAM-1), interleukin-10 (IL-10), macrophage-derived chemokine (MDC), placental growth factor (PLGF), and a disintegrin and metalloproteinase with a thrombospondin type 1 motif (ADAMTS13). On multivariate analysis, higher sVCAM-1 levels were independently predictive of POAF [OR 3.61 (95% CI 1.37-36.91), p=0.003], whereas higher sICAM-1 levels were protective against POAF [OR 0.42 (95% CI 0.16-0.67), p=0.002].

Conclusions: This analysis suggests a relationship between local inflammation in the postoperative pericardial space and alterations in atrial electrophysiology, and supports a potential role for cell adhesion molecules in the mechanism of POAF.