Brain natriuretic peptide concentration in pericardial fluid is independently associated with atrial fibrillation after off-pump coronary artery bypass surgery

The role of pericardial fluid biomarkers in predicting post-operative atrial fibrillation, a comprehensive review of current literature

Post-operative atrial fibrillation (POAF) is a common complication of cardiac surgery which is associated with longer hospital stay, diminished quality of life, and increased mortality. Yet, the pathophysiology of POAF is poorly understood and it is unclear which patients are at highest risk. Pericardial fluid (PCF) analysis is emerging as an important tool for the early detection of biochemical and molecular changes in the cardiac tissue. With the epicardium acting as a semi-permeable membrane, the composition of PCF reflects the activity of the cardiac interstitium. Emerging research on PCF composition has identified promising biomarkers which may help stratify the risk for developing POAF. These include inflammatory molecules, such as interleukin-6, mitochondrial deoxyribonucleic acid, and myeloperoxidase, as well as natriuretic peptides. Additionally, PCF appears to be superior to serum analysis in detecting changes in these molecules during the early postoperative period after cardiac surgery. The aim of the present narrative review is to summarize the current literature on the temporal changes in the levels of potential biomarkers in PCF after cardiac surgery and their association with the development of new-onset postoperative atrial fibrillation.

Metabolic signatures in pericardial fluid and serum are associated with new-onset atrial fibrillation after isolated coronary artery bypass grafting

Postoperative atrial fibrillation (POAF) is a common complication of coronary artery bypass grafting (CABG) procedures. However, the molecular mechanism of POAF remains poorly understood, hence the absence of effective prevention strategies. Here we used targeted metabolomics on pericardial fluid and serum samples from CABG patients to investigate POAF-associated metabolic alterations and related risk prediction of new-onset AF. Nine differential metabolites in various metabolic pathways were found in both pericardial fluid and serum samples from patients with POAF and without POAF. By using machine learning algorithms and regression models, a 4-metabolite (aceglutamide, ornithine, methionine, and arginine) risk prediction model was constructed and showed accurate performance in predicting POAF in both discovery and validation sets. This work extends the metabolic insights of the cardiac microenvironment and blood in patients with POAF and paves the way for the use of targeted metabolomics for predicting POAF in patients with CABG surgery.

Myeloperoxidase Levels in Pericardial Fluid Is Independently Associated with Postoperative Atrial Fibrillation after Isolated Coronary Artery Bypass Surgery

BACKGROUND

Postoperative atrial fibrillation (POAF) is the most common complication after surgery for atherosclerotic cardiovascular disease (ASCVD) and leads to extended hospital stays and increased mortality. Myeloperoxidase (MPO) in postoperative pericardial drainage fluid is associated with an increased risk of POAF; however, the correlations between MPO in intraoperative pericardial fluid and POAF remain largely unknown. The aim of the study was to evaluate whether MPO is associated with POAF.

METHODS

A total of 97 patients with no history of atrial arrhythmia who had undergone coronary artery bypass surgery (CABG) were identified. We prospectively measured the levels of MPO in intraoperative pericardial fluid and blood using the human magnetic Luminex assay. Then, the occurrence of atrial fibrillation was continuously observed by postoperative ECG and telemetry strips until discharge.

RESULTS

Our data showed that POAF occurred in 24 of 97 patients (24.74%). MPO levels in blood were higher in the POAF group than the SR group (p = 0.064). Patients with POAF had significantly higher intraoperative pericardial fluid MPO levels than patients who remained in SR (p = 0.021). There was no significant correlation between pericardial fluid MPO levels and blood MPO levels (r = -0.47, p = 0.770). In a multivariable logistic regression model, pericardial fluid MPO levels were significantly associated with a higher risk of POAF (odds ratio = 1.016, 95% confidence interval, 1.001-1.031; p = 0.031).

CONCLUSIONS

Higher intraoperative pericardial fluid MPO levels are linked with POAF in patients undergoing CABG. This finding provides insight into a possible mechanism of MPO in pericardial fluid increase susceptibility to developing POAF in patients undergoing CABG.

The effects of atorvastatin on the occurrence of postoperative atrial fibrillation after off-pump coronary artery bypass grafting surgery

BACKGROUND

Atrial fibrillation (AF) after coronary artery bypass graft (CABG) surgery is still the most common arrhythmic complication. This study evaluated whether pretreatment with atorvastatin protects against AF after off-pump CABG.

METHODS

One hundred twenty-four patients without a history of AF or previous statin use, who were scheduled to undergo elective off-pump CABG, were enrolled. Patients were randomized to control group (n = 62) or to atorvastatin group (n = 62) who were administered atorvastatin 20 mg/d for 3 days before the surgery. Primary outcome was the incidence of postoperative AF. Secondary outcomes were major adverse cardiac and cerebrovascular events, persistent AF at 1 month, and identification of the markers to predict inhospital postoperative AF.

RESULTS

The incidence of AF was significantly lower in the atorvastatin group than in the control group (13% vs 27%, P = .04). The incidence of major adverse cardiac and cerebrovascular events and persistent AF at 1 month was similar in comparisons between the groups. Postoperative peak N-terminal pro-brain natriuretic peptide levels were significantly higher in the patients with AF (P = .03). Multivariate analysis identified pretreatment with atorvastatin as an independent factor associated with a significant reduction in postoperative AF (odds ratio 0.34, P = .04). Higher postoperative peak N-terminus pro-B-type natriuretic peptide levels were associated with the development of postoperative AF (odds ratio 1.02 per 100 pg/mL, P = .03).

CONCLUSIONS

Pretreatment with atorvastatin significantly reduced the occurrence of postoperative AF after off-pump CABG.