Fibrillation In Cardiac Surgery Research Articles

Postoperative QRS duration to left ventricular end-diastolic diameter ratio as a predictor for the risk of postoperative atrial fibrillation in cardiac surgery: A single-center prospective study

Background and aimsPostoperative atrial fibrillation (POAF) is a frequent complication following cardiac surgery and is associated with adverse clinical outcomes. Our study aimed at determining the clinical and echocardiographic predictors of POAF in patients with cardiac surgery and management of this group of patients may improve their outcome. MethodsWe prospectively enrolled patients from the department of cardiovascular surgery in the Second Hospital of Tianjin Medical University from October 23, 2020 to October 30, 2022, without a history of atrial fibrillation. Cox regression was used to identify significant predictors of POAF. ResultsA total of 217 patients (79 [36.41 %] were female, 63.96 ± 12.32 years) were included. 88 (40.55 %) patients met the criteria for POAF. Cox regression showed that preoperative left atrial diameter (LAD) (HR: 1.040, 95 % CI 1.008–1.073, p = 0.013) and postoperative QRS/LVEDD (HR: 0.398, 95 % CI 0.193–0.824, p = 0.013) and E/e’ (HR: 1.029, 95 % CI 1.002–1.057，p = 0.033) were predictors of POAF. ConclusionPreoperative LAD and postoperative QRS/LVEDD and E/e’ were predictors of POAF in patients undergoing cardiac surgery. Trial registration sitehttp://www.chictr.org.cn Registration numberChiCTR2200063344.

Evaluation of Perioperative Beta-Blockers and Factors Associated with Postoperative Atrial Fibrillation in Cardiac Surgery: A Single Center Experience

Evaluation of Perioperative Beta-Blockers and Factors Associated with Postoperative Atrial Fibrillation in Cardiac Surgery: A Single Center Experience

Prevention of postoperative atrial fibrillation in cardiac surgery: a quality improvement project

PurposePostoperative atrial fibrillation (POAF) has an incidence of 20–60% in cardiac surgery. The Society of Cardiovascular Anesthesiologists and the European Association of Cardiothoracic Anaesthesiology Practice Advisory have recommended postoperative beta blockers and amiodarone for the prevention of POAF. By employing quality improvement (QI) strategies, we sought to increase the use of these agents and to reduce the incidence of POAF among our patients undergoing cardiac surgery.MethodsThis single-centre QI initiative followed the traditional Plan, Do, Study, Act (PDSA) cycle scientific methodology. A POAF risk score was developed to categorize all patients undergoing cardiac surgery as either normal or elevated risk. Risk stratification was incorporated into a preprinted prescribing guide, which recommended postoperative beta blockade for all patients and a postoperative amiodarone protocol for patients with elevated risk starting on postoperative day one (POD1). A longitudinal audit of all patients undergoing cardiac surgery was conducted over 11 months to track the use of prophylactic medications and the incidence of POAF.ResultsFive hundred and sixty patients undergoing surgery were included in the QI initiative from 1 December 2020 to 1 November 2021. The baseline rate of POAF across all surgical subtypes was 39% (198/560). The use of prophylactic amiodarone in high-risk patients increased from 13% (1/8) at the start of the project to 41% (48/116) at the end of the audit period. The percentage of patients receiving a beta blocker on POD1 did fluctuate, but remained essentially unchanged throughout the audit (34.8% in December 2020 vs 46.7% in October 2021). After 11 months, the overall incidence of POAF was 29% (24.9% relative reduction). Notable reductions in the incidence of POAF were observed in more complex surgical subtypes by the end of the audit, including multiple valve replacement (89% vs 56%), aortic repair (50% vs 33%), and mitral valve surgery (45% vs 33%).ConclusionsThis single-centre QI intervention increased the use of prophylactic amiodarone by 28% for patients at elevated risk of POAF, with no change in the early postoperative initiation of beta blockers (46.7% of patients by POD1). There was a notable reduction in the incidence of POAF in patients at elevated risk undergoing surgery.

Preemptive Pharmacogenetic-Guided Metoprolol Management for Postoperative Atrial Fibrillation in Cardiac Surgery: The Preemptive Pharmacogenetic-Guided Metoprolol Management for Atrial Fibrillation in Cardiac Surgery Pilot Trial

To test the hypothesis that implementation of a cytochrome P-450 2D6 (CYP2D6) genotype-guided perioperative metoprolol administration will reduce the risk of postoperative atrial fibrillation (AF), the authors conducted the Preemptive Pharmacogenetic-Guided Metoprolol Management for Atrial Fibrillation in Cardiac Surgery pilot study. Clinical pilot trial. Single academic center. Seventy-three cardiac surgery patients. Patients were classified as normal, intermediate, poor, or ultrarapid metabolizers after testing for their CYP2D6 genotype. A clinical decision support tool in the electronic health record advised providers on CYP2D6 genotype-guided metoprolol dosing. Using historical data, the Bayesian method was used to compare the incidence of postoperative AF in patients with altered metabolizer status to the reference incidence. A logistic regression analysis was performed to study the association between the metabolizer status and postoperative AF while controlling for the Multicenter Study of Perioperative Ischemia AF Risk Index. Of the 73 patients, 30% (n=22) developed postoperative AF; 89% (n=65) were normal metabolizers; 11% (n=8) were poor/intermediate metabolizers; and there were no ultrarapid metabolizer patients identified. The estimated rate of postoperative AF in patients with altered metabolizer status was 30% (95% CI 8%-60%), compared with the historical reference incidence (27%). In the risk-adjusted analysis, there was insufficient evidence to conclude that modifying metoprolol dosing based on poor/intermediate metabolizer status was associated significantly with the odds of postoperative AF (odds ratio 0.82, 95% CI 0.15-4.55, p=0.82). A CYP2D6 genotype-guided metoprolol management was not associated with a reduction of postoperative AF after cardiac surgery.

Long-Term Outcomes of Preoperative Atrial Fibrillation in Cardiac Surgery.

BackgroundAtrial fibrillation (Afib) is a marker of increased cardiovascular morbidity and mortality. Owing to the increased prevalence of Afib in patients undergoing cardiac surgery, assessing the effect of Afib on postsurgical outcomes is important. We aimed to analyze the effect of preoperative Afib on clinical outcomes in patients undergoing cardiac surgery using a large surgical database.MethodsThis retrospective cohort study was based on the national health claims database established by the National Health Insurance Service of the Republic of Korea from 2009 to 2015. Diagnosis and procedure codes were used to identify diseases according to the International Statistical Classification of Diseases, 10th revision.ResultsWe included 1,037 patients (0.1%) who had undergone cardiac surgery from a randomized 1,000,000-patient cohort, and 15 patients (1.5%) treated with isolated surgical Afib ablation were excluded. Of these 1,022 patients, 412 (39.7%), 303 (29.2%), and 92 (9.0%) underwent coronary artery bypass, heart valve surgery, and Cox-maze surgery, respectively. Preoperative Afib was associated with higher patient mortality (p=0.028), regardless of the surgical procedure. Patients with preoperative Afib (n=190, 18.6%) experienced a higher cumulative risk of overall mortality (hazard ratio [HR], 1.435; 95% confidence interval [CI], 1.263–2.107; p=0.034). Subgroup analysis revealed a reduced risk of overall mortality with Cox-maze surgery in Afib patients (HR, 0.500; 95% CI, 0.266–0.938; p=0.031). Postoperative cerebral ischemia or hemorrhage events were not related to Afib.ConclusionPreoperative Afib was independently associated with worse long-term postoperative outcomes after cardiac surgery. Concomitant Cox-maze surgery may improve the survival rate.

Determinants of postoperative atrial fibrillation: A retrospective evaluation of postoperative atrial fibrillation in cardiac surgery

Introduction: Atrial fibrillation is the most common postoperative arrhythmia and is associated with increased length of stay, cost, morbidity and mortality. The incidence of postoperative atrial fibrillation for noncardiac, nonthoracic surgeries ranges from 0.4% to 26%. The incidence increases to 20%–50% in cardiac surgery, occurring in approximately 30% of isolated coronary artery bypass grafting (CABG), approximately 40% of isolated valve surgeries and up to 50% of CABG plus valve surgeries. Our aim was to identify risk factors that may predispose patients to postoperative atrial fibrillation and compare the efficacy of previously developed prediction tools to a new bedside prediction tool. We sought to develop a bedside screening tool using 4 easily identifiable variables: body mass index, age, congestive heart failure and hypertension (BACH). We predicted that our model would compare similarly to previously developed and validated prediction models but would be easier to use.
 Methods: We retrospectively identified 672 patients without a history of atrial fibrillation who had undergone cardiac surgery from July 2011 to December 2018. The risk factors for atrial fibrillation were evaluated alongside previously developed prediction tools. Using logistic regression, t tests and receiver operator characteristic (ROC) analysis, we compared previously used risk stratification scores of CHA2DS2-VASc, CHARGE-AF and age. We also compared our proposed BACH risk prediction tool to our population and compared it against CHA2DS2-VASc, CHARGE-AF and age. In a subpopulation analysis of 259 people, we evaluated if left atrial size was an independent risk factor for the development of postoperative atrial fibrillation.
 Results: A total of 131 patients—approximately 20%—developed postoperative atrial fibrillation. CHA2DS2-VASc had the lowest area under the curve (AUC) and did not perform as well at classifying patients with postoperative atrial fibrillation as the other 3 predictors. CHARGE-AF, age by itself and age per 5 years performed relatively similarly to one another. ROC was greatest for age alone (ROC area .634, 95% CI: .581–.688), followed by CHARGE-AF (ROC area .631, 95% CI: .577–.684), and finally CHA2DS2-VASc (ROC area .564, 95% CI: .509–.619). A logistic model was fit for the BACH variables (continuous versions of body mass index, age, congestive heart failure and hypertension). The model achieved good fit, χ2(671, N=672)=633.029, P=.816, Nagelkerke R2=.070. However, only the predictors of age and prior heart failure were found to be significant. For BACH, the C-statistic (and AUC) for the model was .645 (95% CI: .601, .707), which was marginally better than age alone. All the models that were fit using ROC analyses were not statistically different from one another in terms of performance. No statistical significance was found between the 2 groups for preoperative left atrial size.
 Conclusion: These findings suggest that age may be the highest risk factor for postoperative atrial fibrillation. The bedside prediction tool BACH compared slightly better than age alone but was not statistically different from the other prediction tools’ performance. The BACH prediction tool is easy to use, includes only 4 factors that are readily available at the bedside and improves prediction over age alone.

Predicting Post-operative Atrial Fibrillation in Cardiac Surgery – The Added Value of Echocardiography

INTRODUCTION: Post-operative atrial fibrillation (POAF) is a frequent rhythmic complication in cardiac surgery with the potential to cause sudden hemodynamic instability and catastrophic thromboembolic complications. Despite vast scientific research, it is still hard to predict and prevents its occurrence. AIM: The aim of this study was to determine whether selected pre-operative and intraoperative echocardiographic variables would be of added value in POAF prediction. МАTERIAL AND METHODS: This prospective observational follow-up study included 178 cardiac surgery patients undergoing coronary artery bypass graft intervention. Demographic as well as echocardiographic variables of interest were examined to detect significant independent predictors for POAF. RESULTS: POAF was detected in 90 (50.56%) patients versus 88 (49.44%) patients without POAF. Patients who developed POAF were significantly older and burdened with multiple comorbidities. In multiple regression analysis pre-operative echocardiographic variables-diastolic dysfunctions, enlarged left atrial (LA) volume indexed for body surface area, mitral annular calcification, and secondary mitral regurgitation were predictive of POAF. LA appendage flow velocity obtained by intraoperative transesophageal echocardiography was also a significant intraoperative predictor for POAF. CONCLUSION: The results of this study confirmed that two-dimensional echocardiography is a valuable diagnostic and prognostic tool in relation to POAF. The addition of the aforementioned echocardiographic independent predictors to traditional demographic variables could be a solid foundation of a new predictive model for POAF.

Atrial fibrillation in cardiac surgery

Atrial fibrillation in cardiac surgery

Atrial fibrillation in cardiac surgery.

Atrial fibrillation is the most frequent arrhythmia in the postoperative period of cardiac surgery. It is associated with heart failure, renal insufficiency, systemic embolism and increase in days of in-hospital and mortality. Atrial fibrillation in the postoperative period of cardiac surgery (FAPCC) usually appears in the first 48 h after surgery. The main mechanisms involved in the appearance and maintenance of FAPCC are the increase in sympathetic tone and the inflammatory response. The associated risk factors are advanced age, chronic obstructive pulmonary disease, chronic kidney disease, valve surgery, fraction of ejection of the left ventricle < 40% and the withdrawal of beta-blocker drugs. There are instruments that have been shown to predict the appearance of FAPCC. Prophylactic treatment with beta-blockers and amiodarone, is associated with a decrease in the appearance of FAPCC. Given its transient nature, it is suggested that the initial treatment of FAPCC be the heart rate control and only if the treatment does not achieve a return to sinus rhythm, the use of electrical cardioversion is suggested. It is unknown what should be the long-term follow-up and complications beyond this period are little known. FAPCC is not a benign or isolated arrhythmia in patients undergoing cardiac surgery, so the identification of risk factors, their prevention, and follow-up in the outpatient setting, should be part of the units dedicated to the care and care of these patients.

CYP2D6 Genotype-guided Metoprolol Therapy in Cardiac Surgery Patients: Rationale and Design of the Pharmacogenetic-guided Metoprolol Management for Postoperative Atrial Fibrillation in Cardiac Surgery (PREEMPTIVE) Pilot Study

The Preemptive Pharmacogenetic-guided Metoprolol Management for Atrial Fibrillation in Cardiac Surgery (PREEMPTIVE) pilot trial aims to use existing institutional resources to develop a process for integrating CYP2D6 pharmacogenetic test results into the patient electronic health record, to develop an evidence-based clinical decision support tool to facilitate CYP2D6 genotype-guided metoprolol administration in the cardiac surgery setting, and to determine the impact of implementing this CYP2D6 genotype-guided integrated approach on the incidence of postoperative atrial fibrillation (AF), provider, and cost outcomes. One-arm Bayesian adaptive design clinical trial. Single center, university hospital. The authors will screen (including CYP2D6 genotype) up to 600 (264 ± 144 expected under the adaptive design) cardiac surgery patients, and enroll up to 200 (88 ± 48 expected) poor, intermediate, and ultrarapid CYP2D6 metabolizers over a period of 2 years at a tertiary academic center. All consented and enrolled patients will receive the intervention of CYP2D6 genotype-guided metoprolol management based on CYP2D6 phenotype classified as a poor, intermediate, extensive (normal), or ultrarapid metabolizer. The primary outcome will be the incidence of postoperative AF. Secondary outcomes relating to rates of CYP2D6 genotype-guided prescription changes, costs, lengths of stay, and implementation metrics also will be investigated. The PREEMPTIVE pilot study is the first perioperative pilot trial to provide essential information for the design of a future, large-scale trial comparing CYP2D6 genotype-guided metoprolol management with a nontailored strategy in terms of managing AF. In addition, secondary outcomes regarding implementation, clinical benefit, safety, and cost-effectiveness in patients undergoing cardiac surgery will be examined.

Preemptive Pharmacogenetic-guided Metoprolol Management for PostoperativeAtrial Fibrillation in Cardiac Surgery

Preemptive Pharmacogenetic-guided Metoprolol Management for PostoperativeAtrial Fibrillation in Cardiac Surgery

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.

Left atrial concomitant surgical ablation for treatment of atrial fibrillation in cardiac surgery: A meta-analysis of randomized controlled trials.

IntroductionSurgical ablation is a generally established treatment for patients with atrial fibrillation undergoing concomitant cardiac surgery. Left atrial (LA) lesion set for ablation is a simplified procedure suggested to reduce the surgery time and morbidity after procedure. The present meta-analysis aims to explore the outcomes of left atrial lesion set versus no ablative treatment in patients with AF undergoing cardiac surgery.MethodsA literature research was performed in six database from their inception to July 2017, identifying all relevant randomized controlled trials (RCTs) comparing left atrial lesion set versus no ablative treatment in AF patient undergoing cardiac surgery. Data were extracted and analyzed according to predefined clinical endpoints.ResultsEleven relevant RCTs were included for analysis in the present study. The prevalence of sinus rhythm in ablation group was significantly higher at discharge, 6-month and 1-year follow-up period. The morbidity including 30 day mortality, late all-cause mortality, reoperation for bleeding, permanent pacemaker implantation and neurological events were of no significant difference between two groups.ConclusionsThe result of our meta-analysis demonstrates that left atrial lesion set is an effective and safe surgical ablation strategy for AF patients undergoing concomitant cardiac surgery.

Storage time of intraoperative transfused allogeneic red blood cells is not associated with new-onset postoperative atrial fibrillation in cardiac surgery.

BackgroundAllogeneic red blood cell (RBC) transfusion has been associated with new-onset postoperative atrial fibrillation (POAF) following cardiac surgery. Prolonged storage time of RBC may increase the risk. The primary aim of the study was to evaluate whether the storage time of RBC is associated with development of POAF.Materials and methodsPre-, per- and postoperative data were retrieved from the Western Denmark Heart Registry and local blood banks regarding patients who underwent coronary artery bypass surgery, valve surgery or combined procedures in Aalborg or Aarhus University Hospital during 2010–2014. Multiple logistic regression was used to determine the risk of POAF according to transfusion of RBC on the day of surgery. Furthermore, we determined trend in storage time of RBC according to risk of POAF using restricted cubic splines. Patients with a history of preoperative atrial fibrillation, patients who received transfusions preoperative and patients who died at the day of surgery were among excluded patients.ResultsA total of 2,978 patients with a mean age of 66.4 years were included and 609 patients (21%) received RBC transfusion on the day of surgery. POAF developed in 752 patients (25%) and transfused patients were at an increased risk compared with non-transfused patients (adjusted Odds Ratios for patients receiving RBC: 1.37; 95% CI: 1.11–1.69, P-value = 0.004). However, RBC transfusion was not necessarily the cause of POAF and may only be a marker for development of POAF. There was no significant association between storage time of RBC and POAF.ConclusionsIn contrast to intraoperative allogeneic RBC transfusion in general, increased storage time of RBC is not associated with development of POAF in cardiac surgery.

Marine n-3 fatty acids are incorporated into atrial tissue but do not correlate with postoperative atrial fibrillation in cardiac surgery

ObjectivesPostoperative new-onset atrial fibrillation (POAF) in cardiac surgery is associated with increased morbidity and mortality. Because n-3 polyunsaturated fatty acids (n-3 PUFA) have an antiarrhythmic effect, we hypothesized that a high content of marine n-3 PUFA in the atrial wall was associated with a reduced risk of POAF. DesignVenous blood and tissue from the right atrial appendage were obtained from 50 patients undergoing elective cardiac surgery. We determined the content of marine n-3 PUFA in atrial tissue and in plasma phospholipids using gas chromatography. ResultsThe mean age of the patients (results available from 49 patients) was 66.0±10.4years, and 22, 14, 10 and 3 patients underwent coronary artery bypass surgery, valve, combined or other cardiac surgery, respectively. Eighteen patients (36.7%) developed POAF. Concentrations of n-3 PUFA in the atrial wall and in plasma phospholipids did not predict the development of POAF, but there were significant correlations between marine n-3 PUFA in atrial tissue and plasma. ConclusionLevels of marine n-3 PUFA in the atrial wall was not associated with the risk of POAF following cardiac surgery, despite significant correlations of marine n-3 PUFA in the atrium and in plasma phospholipids.

Pentraxin 3 and other inflammatory biomarkers related to atrial fibrillation in cardiac surgery.

The aim was to evaluate the association between perioperative inflammatory biomarkers and atrial fibrillation (AF) in cardiac surgical patients. Forty-two patients undergoing cardiac surgery were divided into three groups according to the occurrence of AF: Group A (n = 22) - patients with no AF, Group B (n = 11) - patients with new onset AF postoperatively and Group C (n = 9) - patients with preoperative history of atrial fibrillation. The serum levels of PTX3, CRP, TLR2, IL-8, IL-18, sFas, MMP-7 and MMP-8 were measured at the following time points: before surgery, immediately and 6 h after surgery and on the 1st, 3rd and 7th postoperative days (POD). Serum levels of PTX3 showed a significant difference between Groups A and C on the 3rd POD (p<0.05) and on the 7th POD (p<0.0001). IL-8 levels were different between Groups A and C immediately after surgery (p<0.05), 6 hours after surgery (p<0.05) and on the 3rd POD (p<0.05). There was a difference between Groups B and C on the 1st POD in IL-8 levels (p<0.05). The sFas levels differed between Groups A and C on the 3rd POD (p<0.01) and the 7th POD (p<0.05). There was also a difference on the 7th POD (p<0.05) between the Groups B and C. No significant differences between the groups was seen for other biomarkers. This study demonstrates significantly different dynamics of PTX3, IL-8 and sFas levels after cardiac surgery in relation to AF.

Abstract 12783: Postoperative Cardioversions for New-onset Atrial Fibrillation in Cardiac Surgery

Introduction: New-onset postoperative atrial fibrillation (AF) is a frequent complication after open-heart surgery and cardioversions (CV) are often performed to restore sinus rhythm in this setting. Thromboembolic risk related to early postoperative CV and the recurrence of AF in the long-term follow-up, however, remain largely unknown. Hypothesis: The FIN-bioAVR study sought to assess the rate of strokes and transient ischemic attacks (TIA) shortly after CV for AF in patients who underwent isolated aortic valve replacement with bioprosthesis. Methods: Between 2002 and 2014, 784 patients underwent isolated aortic valve replacement with a bioprosthesis in four Finnish University Hospitals. Results: During postoperative hospitalization when patients with prior chronic AF were excluded, 368/685 (53.7%) of patients had at least one new-onset paroxysm of AF (median time to diagnosis 3 [3] days), and early CV was performed in 122/368 (33.2%) of them. Baseline characteristics were comparable except that patients with CV had more often prior diagnosis of heart failure and less often chronic lung disease compared to those without CV. Hospital stay was significantly shorter, but at two-weeks follow-up, the rate of stroke/TIAs was 3.3% vs. 0.4% (p=0.05) in those with vs. without CV, respectively. Strikingly, early CV was associated with a trend of increased risk of two-week stroke/TIA rate compared to patients without CV (OR 7.66 (95%-CI 0.85-69.3, p=0.07)). In the median follow-up of 1682 [1514] days patients with early CV had more often recurrences of clinical AF (57% vs. 39%, p&lt;0.01). Conclusions: In this large real-world population of patients undergoing aortic valve bioprosthesis operation, the rate of new-onset in-hospital AF was over 50%. Nearly third of them had a CV and these patients had over 7-fold risk for thromboembolisms related to CV.

Which beta-blocker should be used for the prevention of postoperative atrial fibrillation in cardiac surgery? A multi-treatment benefit-risk meta-analysis

Abstract Background Post-operative atrial fibrillation (POAF) is amongst the most common complications following cardiac surgery. Current guidelines recommend oral beta-blockers as a first-line medication to prevent POAF. However, the ideal choice of beta-blocker is unclear, making a comprehensive review crucial. We aimed to provide a clinically useful summary of the results of a multiple-treatment meta-analysis of randomized controlled trials (RCT). Methods and Results: A MEDLINE/PubMed search was conducted to identify eligible RCTs. Efficacy (POAF prevention rate) and acceptability (dropout for side effect rate) outcomes were investigated. A frequentist approach to network meta-analysis using the graph-theoretical method was implemented to obtain network estimates. A total of 16 trials were included in the final analysis and 4727 subjects were investigated. Network estimates showed that betaxolol (OR 0.36; 95%CI 0.25–0.52), carvedilol (OR 0.36; 95%CI 0.23–0.58) and sotalol (OR 0.38; 95%CI 0.30–0.50) were more effective than propranolol (OR 0.51; 95%CI 0.27–0.95), metoprolol (OR 0.72; 95%CI 0.58–0.90) and atenolol (OR 0.81; 95%CI 0.42–1.56) in reducing the incidence of POAF when compared to placebo. Amongst beta-blockers investigated, carvedilol showed the best safety profile being associated with the lowest risk of patient dropped out for side effect (OR 1.14; 955CI 0.36–3.61). No evidence of heterogeneity/inconsistency was found in the whole network for both efficacy (P = 0.8) and acceptability (P = 0.4) outcomes. Conclusion: Overall, carvedilol was found to be effective in preventing POAF while maintaining a good safety profile.

Inflammation, oxidative stress and postoperative atrial fibrillation in cardiac surgery.

Postoperative atrial fibrillation (POAF) is a common complication of cardiac surgery that occurs in up to 60% of patients. POAF is associated with increased risk of cardiovascular mortality, stroke and other arrhythmias that can impact on early and long term clinical outcomes and health economics. Many factors such as disease-induced cardiac remodelling, operative trauma, changes in atrial pressure and chemical stimulation and reflex sympathetic/parasympathetic activation have been implicated in the development of POAF. There is mounting evidence to support a major role for inflammation and oxidative stress in the pathogenesis of POAF. Both are consequences of using cardiopulmonary bypass and reperfusion following ischaemic cardioplegic arrest. Subsequently, several anti-inflammatory and antioxidant drugs have been tested in an attempt to reduce the incidence of POAF. However, prevention remains suboptimal and thus far none of the tested drugs has provided sufficient efficacy to be widely introduced in clinical practice. A better understanding of the cellular and molecular mechanisms responsible for the onset and persistence of POAF is needed to develop more effective prediction and interventions.

Obstructive Sleep Apnea Is an Independent Predictor of Postoperative Atrial Fibrillation in Cardiac Surgery

To test the hypothesis that obstructive sleep apnea (OSA) is a risk factor for development of postoperative atrial fibrillation (POAF) after cardiac surgery. Retrospective analysis. Single-center university hospital. Five hundred forty-five patients in sinus rhythm preoperatively undergoing coronary artery bypass grafting (CABG), aortic valve replacement, mitral valve replacement/repair, or combined valve/CABG surgery from January 2008 to April 2011. Retrospective review of medical records. Postoperative atrial fibrillation was defined as atrial fibrillation requiring therapeutic intervention. Of 545 cardiac surgical patients, 226 (41%) patients developed POAF. The risk was higher in 72 OSA patients than 473 patients without OSA (67% v 38%, adjusted hazard ratio 1.83 [95% CI: 1.30-2.58], p<0.001). Of the 32 OSA patients who used home positive airway pressure (PAP) therapy, 18 (56%) developed POAF compared with 29 of 38 (76%) patients who did not use PAP at home (unadjusted hazard ratio 0.63 [95% CI: 0.35-1.15], p = 0.13). OSA is significantly associated with POAF in cardiac surgery patients. Further investigation is needed to determine whether or not use of positive airway pressure in OSA patients reduces the risk of POAF.