Higher Risk Of Postoperative Atrial Fibrillation Research Articles

L-Carnitine: A New Therapeutic Option for the Prevention of Atrial Fibrillation in Non-Cardiac Surgery-A Single-Group Interventional Pilot Study.

Background: L-carnitine is essential in lipid metabolism and reportedly has preventive effects for arrhythmia. Our objective was to examine the incidence of postoperative atrial fibrillation (POAF) and changes in serum biomarker levels following perioperative L-carnitine administration in patients with lung cancer. Methods: Thirteen patients undergoing a lobectomy with preoperative serum brain natriuretic peptide levels >24 pg/mL were perioperatively administered L-carnitine for 5 days (3 g/3×). Accurate 95% confidence intervals (CI) for POAF incidence were calculated. Serum biomarkers for POAF in lung cancer and target proteins for L-carnitine were evaluated by using open-source data from proteomic analysis. Results: The incidence of POAF was 38.5% (95% CI 13.9%-68.4%). Fatty acid-binding protein 4 (FABP4) was selected as a candidate biomarker from 1472, 63, and 26 proteins related to lung cancer, L-carnitine, and AF, respectively. A positive correlation was observed between the predicted POAF incidence rate and preoperative FABP4 levels (Pearson's r = 0.5183). The mean change in serum FABP4 after L-carnitine administration for 5 days was -2.9 ng/mL (95% CI -4.9 to -0.89 ng/mL). Conclusions: The incidence of POAF after a lobectomy was 38.5% after the perioperative administration of L-carnitine for patients at a high risk of POAF. The serum FABP4 level demonstrates potential as a candidate biomarker for POAF prediction.

Left Atrial Strain to Predict Postoperative Atrial Fibrillation in Patients Undergoing Coronary Artery Bypass Grafting.

Postoperative atrial fibrillation (POAF) is a common complication after cardiac surgery being associated with poorer outcomes. Revealing before the operation of left atrial subtle structural/functional abnormalities may help to identify patients at increased risk of POAF. We investigated the role of left atrial strain parameters by preoperative speckle tracking echocardiography as independent predictors of POAF in patients undergoing coronary artery bypass graft. Consecutive patients undergoing isolated coronary artery bypass graft were prospectively enrolled at three Italian centers. All patients underwent transthoracic echocardiography before the operation. The occurrence of POAF up to discharge was monitored. Overall, a total of 310 patients were included. POAF was demonstrated in 103 patients (33%). At receiver operating characteristic curve analysis, lower global peak atrial longitudinal strain (PALS) values significantly predicted the risk of POAF (area under the curve, 0.74; P<0.001). The optimal cutoff value for the arrhythmia prediction was a global PALS value <28%, with a specificity of 86% and a sensitivity of 36%. The incidence of POAF was 51% in patients with global PALS <28% versus 14% in those with PALS ≥28% (P<0.001), with a POAF-free survival at Kaplan-Meier analysis of 45.4% and 85.7%, respectively (P<0.001). At multivariate analysis, a global PALS <28% carried a 3.6-fold higher risk of POAF (hazard ratio, 3.6 [95% CI, 2.2-5.9]; P<0.001). The risk increase was even higher when PALS <28% was associated with age ≥70 years (adjusted hazard ratio, 11.2 [4.7-26.6], P<0.001). A presurgery global PALS <28% is a specific parameter to stratify patients at increased risk of POAF after coronary artery bypass graft. This assessment can be useful to identify patients at higher arrhythmic risk in whom perioperative preventive strategies and stricter monitoring aimed at early diagnosing and treating POAF may be applied.

Characterization of unipolar electrogram morphology: a novel tool for quantifying conduction inhomogeneity.

Areas of conduction inhomogeneity (CI) during sinus rhythm may facilitate the initiation and perpetuation of atrial fibrillation (AF). Currently, no tool is available to quantify the severity of CI. Our aim is to develop and validate a novel tool using unipolar electrograms (EGMs) only to quantify the severity of CI in the atria. Epicardial mapping of the right atrium (RA) and left atrium, including Bachmann's bundle, was performed in 235 patients undergoing coronary artery bypass grafting surgery. Conduction inhomogeneity was defined as the amount of conduction block. Electrograms were classified as single, short, long double (LDP), and fractionated potentials (FPs), and the fractionation duration of non-single potentials was measured. The proportion of low-voltage areas (LVAs, <1 mV) was calculated. Increased CI was associated with decreased potential voltages and increased LVAs, LDPs, and FPs. The Electrical Fingerprint Score consisting of RA EGM features, including LVAs and LDPs, was most accurate in predicting CI severity. The RA Electrical Fingerprint Score demonstrated the highest correlation with the amount of CI in both atria (r = 0.70, P < 0.001). The Electrical Fingerprint Score is a novel tool to quantify the severity of CI using only unipolar EGM characteristics recorded. This tool can be used to stage the degree of conduction abnormalities without constructing spatial activation patterns, potentially enabling early identification of patients at high risk of post-operative AF or selection of the appropriate ablation approach in addition to pulmonary vein isolation at the electrophysiology laboratory.

Age-Related Association between Sex and Postoperative Atrial Fibrillation in Non-Cardiac Surgery Patients: Observational Cohort Study.

Postoperative atrial fibrillation (POAF) is a common complication that has shown conflicting results regarding sex differences. The potential effect of age on this association has not been adequately explored. We hypothesized that younger males would have a higher risk of POAF than females and that this difference would vary by age group. In this observational cohort study, we enrolled consecutive patients who underwent non-cardiac surgery between January 2011 and June 2019 at our institution and excluded those with preoperative atrial fibrillation and those undergoing sex-specific surgery. We stratified the patients into four groups based on their sex and age: females younger than 50 years, females older than 50 years, males younger than 50 years, and males older than 50 years. The primary outcome was the incidence of POAF. Of the 141,337 patients included in the study, 6414 (4.5%) were treated for POAF. The incidence of POAF was highest in males older than 50 years (7.4%), followed by females older than 50 years (4.6%), males younger than 50 years (2.1%), and females younger than 50 years (1.9%). After adjusting for potential confounding factors, the risk of POAF was significantly increased in all groups compared with females younger than 50 years, with an odds ratio (OR) of 2.43 (95% confidence interval [CI]: 2.17-2.73, p 0.001) for females older than 50 years, 1.19 (95% CI: 1.05-1.35, p = 0.01) for males younger than 50 years, and 4.39 (95% CI: 3.91-4.94, p 0.001) for males older than 50 years. The OR for POAF risk according to sex peaked between 60 and 70 years old and decreased gradually thereafter. Our study suggests that sex and age are important factors associated with the risk of POAF in non-cardiac surgery patients and that sex-specific and age-specific risk stratification and interventions might be needed to prevent and manage POAF in non-cardiac surgery patients. Further studies are needed to better understand the underlying mechanisms of sex and age differences in POAF and to develop more targeted and effective interventions to reduce the incidence of this common postoperative complication.

Could We Predict POAF With a Simple Ambulatory Oscillometry Evaluating Aortic Stiffness?

To investigate the relationship between aortic stiffness and postoperative atrial fibrillation (POAF) in patients undergoing coronary artery bypass grafting (CABG). This study included 110 patients undergoing elective isolated CABG. Aortic stiffness was measured using a noninvasive oscillometric sphygmomanometer before surgery. Characteristics of patients with and without POAF were compared. POAF developed in 32 (29.1%) patients. Patients with POAF were older (63.7±8.6 vs. 58.3±8.4; P=0.014). Chronic obstructive pulmonary disease (COPD) was more common in patients with POAF (11.5% vs. 37.5%; P=0.024), whereas the frequency of hypertension, diabetes mellitus, smoking, and previous coronary artery disease did not differ. C-reactive protein and cholesterol levels were similar between patients with and without POAF. Left atrial diameter was greater in patients with POAF (35.9±1.6 vs. 36.7±1.7; P<0.039). Peripheral (p) and central (c) systolic and diastolic blood pressures were also similar between the groups, whereas both p and c pulse pressures (PP) were greater in patients with POAF (pPP: 44.3±11.9 vs. 50.3±11.6; P=0.018, cPP: 31.4±8.1 vs. 36.2±8.9; P=0.008). Pulse wave velocity (PWV) was significantly higher in POAF (8.6+1.3 vs. 9.4+1.3; P=0.006). PWV, pPR and COPD were independent predictors of POAF in multivariate regression analysis. In receiver operating characteristic analysis, PWV and pPP have similar accuracy for predicting POAF (PWV, area under the curve [AUC]: 0.661, 95% confidence interval [CI] [0.547-0.775], P=0.009) (pPP, AUC: 0.656, 95% CI [0.542-0.769], P=0.012). COPD, PWV, and PP are predictors of POAF. PP and PWV, easily measured in office conditions, might be useful for detecting patients with a higher risk of POAF.

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

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. 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. 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). 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.

Abstract 13436: Sex-Specific Predictors of Postoperative Atrial Fibrillation and the Role of Cardiometabolic Diseases

Introduction: Cardiometabolic diseases increase the risk of postoperative atrial fibrillation (POAF), which in turn is associated with higher long-term risk of major cardiovascular events (MACE). Little is known regarding the sex-specific impact of cardiometabolic diseases on POAF risk. We evaluated the sex-specific predictors of POAF after coronary artery bypass grafting (CABG), with a focus on preoperative cardiometabolic profile. Methods: In a prospective registry of patients undergoing isolated CABG (2006-2019), we compared predictors of POAF between sexes. We excluded patients with previous AF history, redo/urgent/off-pump CABG, perioperative mortality, and permanent pacemakers/defibrillators. Abdominal obesity was defined as a waist circumference (WC) &gt;102 cm (men [M]) or &gt;88 cm (women [W]). Results: We included 7,851 patients (19% women). Baseline characteristics are presented in Table 1. POAF occurred in 27% of women and 31% of men (p&lt;0.01). Women were older and had a higher prevalence of comorbidities, abdominal obesity and a worse lipid profile. In a logistic regression model adjusting for the variables in Table 1, men had a higher risk of POAF (OR M = 1.4 [1.2-1.6], p&lt;0.01). When stratifying by sex, significant predictors (p&lt;0.05) of POAF for both sexes were age, WC (OR M = 1.04 [1.00-1.08]; OR W = 1.01 [1.00-1.03]), and triglycerides (TG) (OR M = 0.98 [0.97-0.99]; OR W = 0.97 [0.95-0.99]). Sex-specific predictors were creatinine for women and beta-blockers, extracorporeal circulation time, intensive care stay and hemoglobin for men. Conclusions: Women had less POAF but worse preoperative cardiometabolic profile compared to men. WC was a strong predictor of POAF for both sexes, while higher TG levels were protective. Since POAF is linked to future risk of MACE, the preoperative clinical assessment of WC should be encouraged and targeted for preventive strategies, especially in women. More studies are needed to investigate the role of TG in POAF.

First experience of using two-dimensional speckle-tracking echocardiography to assess the association of left atrial strain with atrial fibrillation after coronary artery bypass grafting

Aim. To assess left atrial (LA) strain parameters in candidates for coronary artery bypass grafting (CABG) and to evaluate their possible relationship with newly diagnosed atrial fibrillation (AF) after isolated CABG.Material and methods. The study Included 70 patients without prior AF (mean age, 65±8 years; men, 80%). Preoperative speckle-tracking echocardiography with an assessment of LA strain was performed. Two following groups were considered: without postoperative AF (POAF) (n=50), with postoperative POAF (n=20). After surgery, daily electrocardiography (ECG), 3-day postoperative continuous ECG monitoring, Holter ECG monitoring on the 4th-5th day after CABG. The median follow-up was 9 (7; 11) days.Results. Postoperative AF developed in 20/70 (29%) patients. Clinical, demographic and intraoperative parameters of CABG in the groups without and with POAF were comparable. Echocardiographic parameters in the studied groups were also equivalent; LA volume (57,0±8,7 vs 60,0±12,1, respectively), LA size (3,9±0,3 vs 3,9±0,2, respectively). Strain analysis showed its significant decrease in the group with POAF compared to the group without POAF: peak atrial longitudinal strain (PALS) (20,4±3,1 vs 27,8±3,0, respectively), ALS early (8,50±1,5 vs 11,8±1,7, respectively), ALS late (-0,2±0,7 vs -1,0±1,0). ROC analysis established the predictive value of PALS as follows: a value of ≤23,0% with a sensitivity of 90% and a specificity of 78% was a predictor of postoperative AF.Conclusion. Conventional echocardiographic predictors (LA size and volume) indicating a high risk of POAF cannot correctly assess the risk of newly diagnosed postoperative arrhythmia. AF after CABG is probably associated with the existing subclinical LA dysfunction as a result of structural abnormalities due to coronary artery disease. Our study showed that a decrease in LA strain parameters is associated with POAF. Further studies are needed to evaluate the contribution of speckle-tracking echocardiography to prediction of POAF.

Right ventricular diastolic function predicts clinical atrial fibrillation after coronary artery bypass graft.

Background:Patients with moderate-severe left ventricular systolic dysfunction undergoing coronary artery bypass graft (CABG) surgery are at high risk of mortality and morbidity. Our aim is to evaluate the right ventricular (RV) diastolic function in these patients, and monitor its effects on postoperation outcomes.Materials and Methods:In a cohort study, patients with moderate-severe left ventricular systolic dysfunction (ejection fraction ≤35%) who were candidate for CABG were included. Baseline transthoracic echocardiography (TTE) was performed, and RV diastolic function measures were obtained. After CABG, the length of intubation, inotrope dependency, hospital stay in intensive care unit and ward, in-hospital and after discharge mortality, postoperative atrial fibrillation (POAF) were evaluated in all patients.Results:Sixty-seven patients were prospectively included in the study. The mean ± standard deviation age of our patients was 61.4 ± 9.3. There was no difference between grades of RV diastolic function and postoperative outcomes. However, we found significant difference between grades of RV diastolic function and onset of in hospital, and total POAF (P-value = 0.017). Multivariate analysis demonstrated that preoperative tricuspidEt/E’t (ratio of peak early-diastolic flow rate across the tricuspid valve orifice to peak early-diastolic velocity at the lateral tricuspid annulus), left atrial volume and “high risk” Euroscore II were independent predictors for POAF during hospitalization and total POAF in patients with moderate to severely impaired left ventricular systolic function (P-values were 0.04, 0.003 and 0.001, respectively).Conclusion:We believe that patients with increased tricuspid Et/E’t are high risk for POAF; therefore, any risk score for POAF should include a comprehensive TTE including evaluation of RV diastolic function before surgery.

Dose-response relationship among body mass index, abdominal adiposity and atrial fibrillation in patients undergoing cardiac surgery: a meta-analysis of 35 cohorts.

BackgroundWhether overweight increases the risk of postoperative atrial fibrillation (POAF) is unclear, and whether adiposity independently contributes to POAF has not been comprehensively studied. Thus, we conducted a meta-analysis to clarify the strength and shape of the exposure-effect relationship between adiposity and POAF.MethodsThe PubMed, Cochrane Library, and EMBASE databases were searched for revelant studies (randomized controlled trials (RCTs), cohort studies, and nest-case control studies) reporting data regarding the relationship between adiposity and the risk of POAF.ResultsThirty-five publications involving 33,271 cases/141,442 patients were included. Analysis of categorical variables showed that obesity (RR: 1.39, 95% CI [1.21–1.61]; P < 0.001), but not being underweight (RR: 1.44, 95% CI [0.90–2.30]; P = 0.13) or being overweight (RR: 1.03, 95% CI [0.95–1.11]; P = 0.48) was associated with an increased risk of POAF. In the exposure-effect analysis (BMI) was 1.09 (95% CI [1.05–1.12]; P < 0.001) for the risk of POAF. There was a significant linear relationship between BMI and POAF (Pnonlinearity = 0.44); the curve was flat and began to rise steeply at a BMI of approximately 30. Notably, BMI levels below 30 (overweight) were not associated with a higher risk of POAF. Additionally, waist obesity or visceral adiposity index was associated with the risk of POAF.ConclusionBased on the current evidence, our findings showed that high body mass index or abdominal adiposity was independently associated with an increased risk of POAF, while underweight or overweight might not significantly increase the POAF risk.

Predictive value of preoperative echocardiographic assessment for postoperative atrial fibrillation after esophagectomy for esophageal cancer.

Postoperative atrial fibrillation (POAF) after esophagectomy for esophageal cancer is not uncommon. The aim of this study is to examine whether preoperative transthoracic echocardiography is useful for predicting new-onset POAF in esophageal cancer. In this prospective observational study, we evaluated 200 patients with esophageal cancer who underwent esophagectomy at our hospital between January 2016 and July 2019. Conventional echocardiographic assessment and tissue Doppler imaging were performed before surgery. We investigated the utility of preoperative transthoracic echocardiography for predicting new-onset POAF in esophageal cancer. New-onset POAF occurred in 51 (25.5%) of 200 patients. POAF was significantly associated with older age (p = 0.007), higher body mass index (p = 0.020), preoperative hypertensive disease (p = 0.021), and lower hemoglobin level (p = 0.028). The incidence of postoperative complications was significantly higher in patients with POAF than in patients without POAF (43.1% vs. 24.2%, p = 0.013). Transthoracic echocardiography showed that left atrial diameter (LAD) and E wave/e' wave ratio (E/e') were significantly higher in patients with POAF than in patients without POAF (34.1 vs. 31.3mm, p < 0.001 and 11.6 vs. 10.5, p = 0.003, respectively). Multivariate analysis showed that LAD ≥ 36.0mm, E/e' ≥ 8.4 are independent risk factors for POAF (odds ratios 2.47 and 3.64; p values 0.035 and 0.027, respectively) CONCLUSIONS: Preoperative echocardiographic evaluation is useful for predicting the onset of POAF after esophagectomy for esophageal cancer. Risk stratification using LAD and E/e' enables clinicians to identify patients at high risk for POAF before esophagectomy.

CHA2DS2-VASc Score for Identifying Patients at High Risk of Postoperative Atrial Fibrillation After Cardiac Surgery: A Meta-analysis

Postoperative atrial fibrillation (POAF) is a common complication after cardiac surgery, resulting in an increased risk of morbidity and longer hospital stay. Pharmacologic prophylaxis has been recommended to improve the outcome in patients at high risk of developing POAF after cardiac surgery. Several studies have applied the CHA2DS2-VASc (Congestive heart failure, Hypertension Age [≥65= 1 point, ≥75= 2 points], Diabetes, and Stroke/transient ischemic attack (2 points)-vascular disease [peripheral arterial disease, previous myocardial infarction, aortic atheroma]) score in the risk stratification of POAF but yielded contradicting results. This study aims to determine the association between CHA2DS2-VASc score and POAF and further to explore its discriminative ability for the prediction of POAF. We systematically searched the Medline, Embase, Cochrane library, and other data sources with key terms "CHA2DS2-VASc," "atrial fibrillation," and "cardiac surgery." Studies designed for CHA2DS2-VASc score in stratifying the risks of POAF in patients undergoing cardiac surgery were included. Statistical analyses were performed with R 3.5.1 and STATA 13.0. Seven hundred twenty-one studies were identified, of which 12 studies with 18,086 patients were finally included in our analysis. The CHA2DS2-VASc score was found to be an independent predictor of POAF after cardiac surgery (odds ratio, 1.46; 95% confidence interval [CI], 1.25-1.72) and exhibited a relatively strong specificity (0.70; 95% CI, 0.61-0.78) and sensitivity (0.72; 95% CI, 0.54-0.85) for predicting POAF. The bivariate model-based pooled area under the receiver operating curve was estimated to be 0.76 (95% CI, 0.72-0.79). The CHA2DS2-VASc score has relatively good performance in predicting POAF after cardiac surgery and may help identify the patients at high risk of POAF.

Post Cardiovascular Surgery Atrial Fibrillation. Biomarkers Determining Prognosis.

New onset of atrial fibrillation (AF) after cardiovascular surgery is associated with increased risk of complications and length of hospital stay. Identification of patients at high risk of post-operative AF (POAF) may help to act with preventive strategies having clinical and economic relevance. The focus of this review is to summarize findings on biomarkers of myocardial fibrosis (PICP and PIIINP), profibrotic mediators (TGF-beta1), extracellular matrix remodeling (MMP-9), myocardial stretch (BNP and NTpro-BNP), inflammation (interleukins, C-reactive protein and sCD40L), and myocardial necrosis (high-sensitivity troponin T), biomarkers, that can be used in clinical practice to stratify patients at risk for POAF. We searched English-language studies on MEDLINE and PubMed. Evidence synthesis was based on cohort studies, clinical trials and meta-analysis data. International clinical practice guidelines were reviewed, as well. Factors such as cardiac remodelling, atrial pressure, surgery trauma, inflammation, oxidative stress, and sympathetic/parasympathetic activation have been implicated in the development of POAF. On the basis of multifactorial mechanism underlying the onset of POAF, several studies have investigated the predictive value of some serum biomarkers. To date, there are promising preliminary data on the clinical utility of PICP, PIINP, TGF-β1 and sCD40L, whereas data on NT-proBNP, BNP, CRP, IL- 6, and hs-cTnT are controversial. Although some studies have shown promising results, there is a need for future larger studies with longer follow-up, before applying biomarkers as tools for POAF risk-stratification into clinical practice.

Predictive factors of new onset postoperative atrial fibrillation in cardiac surgery

Atrial fibrillation is the most frequently encountered arrhythmia and is a well recognized complication of cardiac surgery with a reported incidence of 30% after coronary artery bypass grafting (CABG). The study's purpose was to evaluate postoperative atrial fibrillation (POAF)’s incidence after CABG and to determine its potential predictive factors. It was a retrospective study which included 100 patients who underwent non emergent CABG, from January until December 2017. Non-inclusion criteria were: preoperative atrial fibrillation, more than mild valvular heart disease or a concomitant valvular surgery, and postoperative shock. The sex ratio was 0,19 with 16 women and 84 men. The average age was 60.4 ± 9.5 years. POAF was observed in 18 patients. The average body mass index (BMI) was 26,8 ± 5.5 kg/m 2 . There was no significant correlation between BMI and POAF ( P = 0.29). Only 11 patients (61%) in the POAF group were taking Beta Blockers (BB) in the preoperative period, while 87,8% of the second group with no POAF, were receiving it, with a statistically significant difference ( P = 0.012). The time limit for resuming BBs in the postoperative period was significantly correlated with POAF occurrence ( P = 0.02). After analysing ROC curve we found that resuming BBs beyond the second postoperative day was associated with a significantly higher rate of POAF ( P = 0.001). The biological assessment revealed that 39% among POAF group had chronic renal failure (Cl < 60 ml/min), while 13,4% of the remaining patients had renal impairment ( P = 0.018). Multivariate logistic regression analysis revealed that only renal impairment ( P = 0.041; OR = 4.2) and BB resuming beyond the second postoperative day P = 0.006; OR = 7.5) were independent predictive factors of POAF. There is strong evidence that a delayed postoperative taking of BBs and preoperative renal impairment are associated with a higher risk of POAF.

Prospective External Validation of Three Preoperative Risk Scores for Prediction of New Onset Atrial Fibrillation After Cardiac Surgery.

Postoperative atrial fibrillation (POAF) is associated with early and late morbidity and mortality of cardiac surgical patients. Prophylactic treatment of atrial fibrillation (AF) has been recommended to improve outcome in cardiac surgical patients at high risk of developing POAF. Reliable models for prediction of POAF are needed to achieve that goal. This study attempted to externally validate 3 risk models proposed for preoperative prediction of POAF in cardiac surgical patients: the POAF score, the CHA2DS2-VASc score, and the Atrial Fibrillation Risk Index. This was a prospective cohort study of 1416 adult patients who underwent nonemergent coronary artery bypass graft and/or valve surgery in a single cardiac surgical center between February 2014 and September 2015. A risk score for each of the 3 prediction models was calculated in each patient. All patients were followed for up to 2 weeks, or until hospital discharge, to observe the primary outcome of new onset AF requiring treatment. Discrimination was assessed using receiver operating characteristic curves. Calibration was assessed using the Pearson χ goodness-of-fit test and calibration plots. Utility of the score to implement AF prophylaxis based on the risk of POAF, in comparison to strategies of treating all patients, or not treating any patients, was assessed via a net benefit analysis. Of the 1416 patients included in this study, 478 had the primary outcome (33.8%). The areas under the receiver operating characteristic curve for prediction of POAF in the population subsets for which the scores were validated were as follows: 0.651 (95% confidence interval [CI], 0.621-0.681) for the POAF score, 0.593 (95% CI, 0.557-0.629) for the CHA2DS2-VASc score (P < .001 versus POAF score, P < .222 versus Atrial Fibrillation Risk Index), and 0.563 (95% CI, 0.522-0.604) for the Atrial Fibrillation Risk Index (P < .001 versus POAF score). The calibration analysis showed that the predictive models had a poor fit between the observed and expected rates of POAF. Net benefit analysis showed that AF preventive strategies based on these scores, and targeting patients with moderate or high risk of POAF, improve decision-making in comparison to preventive strategies of treating all patients. The 3 prediction scores evaluated in this study have limited ability to predict POAF in cardiac surgical patients. Despite this, they may be useful in preventive strategies targeting patients with moderate or high risk of PAOF in comparison with preventive strategies applied to all patients.

Preoperative Antihypertensive Medication in Relation to Postoperative Atrial Fibrillation in Patients Undergoing Cardiac Surgery: A Meta-Analysis.

Background. We undertake a systematic review and meta-analysis to evaluate the effect of preoperative hypertension and preoperative antihypertensive medication to postoperative atrial fibrillation (POAF) in patients undergoing cardiac surgery. Methods. We searched PubMed, Embase, and Cochrane Library (from inception to March 2016) for eligible studies. The outcomes were the effects of preoperative hypertension, preoperative calcium antagonists regimen, preoperative ACE inhibitors regimen, and preoperative beta blocking agents regimen with POAF. We calculated pooled risk ratios (OR) and 95% CIs using random- or fixed-effects models. Results. Twenty-five trials involving 130087 patients were listed. Meta-analysis showed that the number of preoperative hypertension patients in POAF group was significantly higher (P < 0.05), while we found that there are no significant differences between two groups in Asia patients by subgroup analysis, which is in contrast to other outcomes. Compared with the Non-POAF group, the number of patients who used calcium antagonists and ACE inhibitors preoperatively in POAF group was significantly higher (P < 0.05). And we found that there were no significant differences between two groups of preoperative beta blocking agents used (P = 0.08). Conclusions. Preoperative hypertension and preoperative antihypertensive medication in patients undergoing cardiac operations seem to be associated with higher risk of POAF.

Prognostic value of strain and strain rate in the prediction of postoperative atrial fibrillation in patients undergoing coronary artery bypass grafting: a systematic literature review

Introduction: Atrial fibrillation (AF) is a common dysrhythmia postoperatively after coronary artery bypass grafting (CABG). Myocardial strain and strain-rate imaging is used for the assessment of postoperative atrial fibrillation (POAF) as a new echocardiographic method. Methods: PubMed and Scopus were searched thoroughly using the following search terms: (strain and strain rate) AND (atrial fibrillation OR AF) on March 2015 to find English articles in which the strain and strain-rate echocardiographic imaging had been used for the evaluation of AF in patients undergone CABG. Full text of the relevant papers was fully reviewed for data extraction.Result: Of overall 6 articles found in PubMed, 10 records found in Scopus and 4 articles found through reference list search, only 6 papers fully met the inclusion criteria for further assessment and data extraction. The results of strain and strain-rate assessment showed that in total of 542 patients undergoing CABG, POAF occurred in 106 patients. Studies showed that the reduction of left atrial (LA) strain rate is correlated with AF. Consistently, the results of present review showed that LA strain and strain-rate in patients who developed AF postoperatively after CABG are significantly reduced, suggesting that strain and strain-rate could be a predictor of POAF.Conclusion: Based on the obtained results, strain and strain-rate is a suitable and accurate echocardiographic technique in the assessment of left atrial function , and it might be helpful to detect the patients who are at high risk of POAF.

Abstract P295: Oxidative Stress Biomarkers and Incidence of Post-Operative Atrial Fibrillation in the OPERA Trial

Background: Post-operative atrial fibrillation (PoAF) commonly complicates cardiac surgery. Animal studies point to oxidative stress as a key mechanism triggering PoAF, and yet, the extent to which oxidative stress might relate to PoAF risk in humans remains speculative. Methods and Results: We assessed the association of validated oxidative stress biomarkers (F 2 -Isoprostanes, F 2 -IsoP, Isofurans, IsoF, and F 3 -Isoprostanes, F 3 -IsoP) in plasma and urine, with incident PoAF among 551 cardiac surgery patients. Biomarkers were measured using standardized methods at baseline, the end of surgery, and post-op day 2. PoAF lasting ≥ 30seconds was confirmed by rhythm strip or ECG, and centrally adjudicated. Outcomes were assessed until hospital discharge or post-operative day 10, whichever occurred first. Urine level of each oxidative stress biomarkers demonstrated a rise at the end of surgery (2-3 fold over baseline, P &lt;0.001), which subsequently fell and were comparable to baseline by post-op day 2. In contrast, plasma levels remained relatively stable throughout. Urine F 2 -iso and IsoF at the end of surgery were 20% and 50% higher in subjects who developed PoAF ( P ≤ 0.009). Baseline biomarker levels did not associate significantly with PoAF, whereas end of surgery and post-op day 2 Isop and IsoF did associate with PoAF. For example, the end of surgery extreme quartile multivariate adjusted odds ratio (95% CI) for urine IsoF and F 3 -IsoP were 1.95 (1.05-3.62; P for trend = 0.01) and 2.10 (1.04-2.25, P for trend = 0.04), respectively. Analyses using restricted cubic splines suggested continuous (monotonic) associations of biomarkers of oxidative stress at the end of surgery and post-op day 2 with incident PoAF ( Figure ) There was little evidence that associations of IsoP and IsoF with PoAF varied by demographic, surgery type, and medication use ( P ≥ 0.29 for each). Conclusions: Elevated end of surgery and post-op day 2 oxidative stress as assessed by IsoP and IsoF relate independently to higher risk of PoAF.

Circulating cardiac biomarkers and postoperative atrial fibrillation in the OPERA trial.

Postoperative atrial fibrillation (POAF) is a common complication after cardiac surgery and predicts increased morbidity and mortality. Identification of patients at high risk of POAF with the help of circulating biomarkers may enable early preventive treatment but data are limited, especially in contemporary surgical patients. Plasma concentrations of N-terminal pro-B-type natriuretic peptide (NT-proBNP) and high-sensitivity cardiac troponin T (hs-cTnT) were measured at enrollment, on the morning of cardiac surgery, at end surgery, and 2 days postsurgery in 562 patients undergoing cardiac surgery, randomized to perioperative supplementation with oral fish oil or placebo in the Omega-3 Fatty Acids for Prevention of Post-Operative Atrial Fibrillation trial (OPERA). The primary endpoint was incident POAF lasting ≥ 30 s, centrally adjudicated and confirmed electrocardiographically. Higher levels of NT-proBNP and hs-cTnT before surgery were associated with older age, renal or cardiac dysfunction and EuroSCORE. NT-proBNP peaked on postoperative day 2 (2172 [1238-3758] ng/L, median [Q1-Q3]), while hs-cTnT peaked at the end of surgery (373 [188-660] ng/L). Fish oil supplementation did not alter the time course of the cardiac biomarkers (P > 0.05). Concentrations of NT-proBNP or hs-cTnT, on the morning of surgery, or changes in their level between morning of surgery and postsurgery, were not significantly associated with POAF after adjustment for clinical and surgical characteristics. Among patients undergoing cardiac surgery, NT-proBNP and hs-cTnT are related to clinical and surgical characteristics, have different perioperative time courses but are not independently associated with risk of POAF.

Abstract 12364: Circulating Cardiac and Inflammatory Biomarkers to Predict Post-Operative Atrial Fibrillation in the OPERA Trial

Objectives: Post-operative atrial fibrillation (POAF) is a common complication after cardiac surgery and predicts increased morbidity and mortality. Identification of patients at high risk of POAF with the help of circulating biomarkers may enable early preventive treatment but data are limited, especially in contemporary surgical patients. Methods: Plasma concentrations of N-terminal probrain natriuretic peptide (NT-proBNP), high sensitivity cardiac troponin T (hs-cTnT) and C-reactive protein (hsCRP) were measured at enrollment, on the morning of cardiac surgery, at end-surgery, and 2 days post-surgery in 562 patients undergoing cardiac surgery, randomized to perioperative supplementation with oral fish oil or placebo in the international clinical trial Omega-3 Fatty Acids for Prevention of Post-Operative Atrial Fibrillation trial (OPERA). The primary endpoint was incident POAF lasting ≥ 30 seconds, centrally adjudicated and confirmed electrocardiographically. Results: Higher levels of NT-proBNP and hs-cTnT before surgery were associated with older age, renal or cardiac dysfunction and higher EuroSCORE, while hsCRP correlated positively with BMI. NT-proBNP (2172 [1238-3758] ng/L) and hsCRP (118 [75-165] mg/L) peaked on post-operative day 2, while hs-cTnT peaked at the end of surgery (373 [188-660] ng/L). Fish oil supplementation did not alter the time course of the cardiac or inflammatory biomarkers. Concentrations of the 3 biomarkers, on the morning of surgery, or changes in their level between morning of surgery and post-surgery, were not significantly associated with POAF after adjustment for clinical and surgical characteristics. Conclusions: Among patients undergoing cardiac surgery, cardiac markers are related to clinical and surgical characteristics, have different perioperative time courses but do not help in predicting the risk of POAF.