Postoperative Atrial Fibrillation Groups Research Articles

Predictors and mortality of new onset postoperative atrial fibrillation after STAAD surgery: a retrospective cohort study.

Data on new onset postoperative atrial fibrillation (POAF) after Stanford type A dissection (STAAD) surgery was limited. This study aimed to detect the risk factors for developing POAF after STAAD procedures and the association between POAF and in-hospital mortality. A total of 1354 patients who underwent surgical treatment for STAAD in Beijing Anzhen hospital were enrolled in this single-center retrospective study from January 2015 to October 2020. POAF were defined as atrial fibrillation/flutter requiring treatment after surgery procedure. Logistic model was conducted to detect the predictors of POAF, and inverse probability of treatment weighting (IPTW) and subgroup analysis were used to compare the mortality of POAF and non-POAF groups. There were 176 patients (13.0%) diagnosed with POAF according to the definition. Multivariate logistics analyses revealed that advanced age [odds ratio (OR), 1.07; 95% CI: 1.05-1.08; P <0.001)], creatinine (OR, 1.00; 95% CI: 1.00-1.01; P =0.001) and cross-clamp time (OR, 1.00; 95% CI: 1.00-1.01; P =0.021) were independent risk factors of developing POAF in STAAD patients. POAF patients were associated with significantly higher in-hospital mortality compared with non-POAF patients (6.5 vs. 19.9%, OR, 3.60; 95% CI: 2.30-5.54; P <0.001), IPTW and subgroup analysis had reached consistent conclusions. The incidence of POAF was 13.0% after STAAD surgery, advanced age, creatinine, and cross-clamp time were independent risk factors of developing POAF in STAAD patients. POAF is associated with increased mortality after STAAD procedures.

Effects of Short-Term Episodes of Atrial Fibrillation after Coronary Artery Bypass Grafting on the Long-term Incidence of Atrial Fibrillation and Ischemic Stroke.

To explore whether postoperative atrial fibrillation (POAF) has an impact on the incidence of late atrial fibrillation (AF) and late ischemic stroke after isolated coronary artery bypass grafting (CABG) compared to non-POAF patients. A total of 243 eligible patients were followed for five years, and divided into a POAF group (n = 69) and a non-POAF group (n = 174). The primary end point was the incidence of late AF, and late ischemic stroke. Kaplan-Meier analyses and Cox proportional hazards models were used to examine whether POAF is an independent risk factor for the occurrence of late AF and late ischemic stroke. POAF patients were older than non-POAF patients. During the 5-year follow-up, the late occurrence of AF was significantly higher in POAF patients than in non-POAF (15.9% vs. 7.9% p = 0.006). There was no significant difference in the incidence of late ischemic stroke between POAF and non-POAF groups (p = 0.406). COX proportional regression analysis showed that POAF was independently associated with the late occurrence of AF (hazard ratio (HR) 3.27; 95% confidence interval (CI): 1.33-8.03, p = 0.01). POAF is an independent risk factor for the occurrence of late AF but not stroke after isolated CABG.

Atrial Fibrillation after Coronary Bypass Surgery? Is Epicardial Fat a Risk Factor?

Postoperative atrial fibrillation (POAF) is one of the most common complication of cardiac surgery. Epicardial fat tissue may play a role in the development of atrial fibrillation (AF). The aim of this study was to evaluate relationship between epicardial fat volume (EFV) and the appearance of new-onset AF in patients undergoing isolated coronary artery bypass graft (CABG) with normal echocardiographic functions. Between January 2017 and June 2020, 281 coronary artery disease patients undergone isolated CABG surgery with normal echocardiographic functions were included in the study. Patient characteristics, medical history, and perioperative variables were retrospectively collected. Patients with AF predisposition factors were excluded. Sixty-seven patients (23.8%) developed postoperatively AF during hospital stay. In univariate analysis, patients with postoperative AF were older compared with sinus rhythm patients (60.78 ± 9.03 vs. 65.46 ± 9.22, p = 0.001). There are no statistically significant differences between groups and EFV compared (107.78 ± 41.04 vs. 106.66 ± 34.98 p = 0.84). Large left atrial diameter, female patient, cardiopulmonary bypass and longer cross-clamp time showed correlation between POAF without statistical significance. Aging is the only associated factor with AF in this study. There was no EFV difference between POAF and non-AF groups in patients undergoing isolated CABG with normal echocardiographic functions.

Early pharmacologic conversion of atrial fibrillation after off-pump coronary artery bypass grafting.

BackgroundThe aim of this study was to evaluate the efficacy of early amiodarone-based pharmacological cardioversion for postoperative atrial fibrillation (POAF) following off-pump coronary bypass grafting (OPCAB).MethodsA total of 507 patients who underwent OPCAB between 2015 and 2017 were categorized into POAF (n=94) and no-POAF (n=413) groups. Patients in the POAF group were treated according to the following institutional protocol: 150 mg loading dose of intravenous amiodarone, followed by oral administration with sequential maintenance doses at 600, 400, and 200 mg per day. If sinus rhythm was restored before discharge, patients were discharged without amiodarone or anticoagulants, except for dual antiplatelets.ResultsBefore discharge at index hospitalization, 97.8% of POAF patients had restored sinus rhythm. Independent risk factors for POAF were age, unstable angina, prior percutaneous transluminal coronary angioplasty, and left atrial diameter. The mean follow-up duration was 41.1±12.8 months. Freedom from overall mortality and composite events, including mortality, major bleeding requiring admission and cerebrovascular events, were similar between the 2 groups. Results were consistent after propensity-score matching.ConclusionsAmiodarone-based rapid pharmacological cardioversion of POAF resulted in a high sinus rhythm conversion rate (97.9%). Rate of late adverse cardiovascular events including stroke, were low even without anticoagulation. As optimal treatment and anticoagulation guidelines for POAF after OPCAB have not yet been established, amiodarone-based treatment protocols may be considered as a useful option.

Inflammatory and Antioxidant Gene Transcripts: A Novel Profile in Postoperative Atrial Fibrillation

Postoperative atrial fibrillation (POAF) is the most common complication after cardiac surgery; however, antiarrhythmic strategies have not lowered the rate of POAF. This study aimed to identify specific gene transcripts of atrial inflammation, inflammatory handling, and oxidative stress associated with POAF. Left atrial tissue was obtained from 50 patients undergoing intended degenerative mitral repair who did not have any of the following risk factors for POAF: history of atrial fibrillation or other arrhythmia, left atrial diameter greater than 6.0 cm, or left ventricular ejection fraction less than 40%. Postoperative outcomes and left atrial tissue messenger ribonucleuc acid (mRNA) levels were recorded. Parametric 2-sample t-tests and chi-square tests were used to evaluate for statistical significance in comparing POAF and non-POAF groups. Within 30 days of surgery, 19 of 50 of patients (38%) developed POAF. There were no significant preoperative, intraoperative, or postoperative differences between POAF and non-POAF patients. In the tissue transcriptome analysis, POAF patients were found to have a worse preoperative inflammatory state with higher levels of tumor necrosis factor alpha, Interleukin-6, and nuclear factor of kappa light polypeptide gene enhancer in B-cells mRNA, worse inflammatory handling capacity with lower levels of nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor mRNA, and reduced antioxidant defenses with lower levels of glutathione synthetase, glutathione reductase, and mitochondrial superoxide dismutase 2 mRNA. This study found POAF patients to have preoperative left atrial tissue profiles suggestive of more inflammation, worse inflammatory handling, and reduced antioxidant defenses against oxidative stress. Investigation of therapies targeted to the tissue-specific inflammatory transcriptome of POAF patients is warranted.

Postoperative Atrial Fibrillation in Lung Cancer Lobectomy-Analysis of Risk Factors and Prognosis.

The incidence of postoperative atrial fibrillation (POAF) after pulmonary lobectomy ranges from 6.4 to 12.6%. This study aimed to analyze the postoperative risk factors and prognosis for POAF in lobectomy for lung cancer. Data were collected from patients undergoing pulmonary lobectomy from April 2010 to March 2019. We analyzed risk factors for POAF among perioperative factors and compared postoperative complications or overall survival between POAF and non-POAF groups. We classified POAF as either the temporary or non-temporary type and compared perioperative factors, postoperative complications, and overall survival. POAF was identified in 49 (5.2%) of the 947 lobectomies. The POAF group included more males, patients with poor performance status (PS), history of paroxysmal atrial fibrillation (AF), chronic obstructive pulmonary disease (COPD), and intraoperative blood transfusions. Poor PS, COPD, previous paroxysmal AF, and intraoperative blood transfusion were independent risk factors for POAF in multivariate analysis. The POAF group had a poorer prognosis than the non-POAF group (p = 0.0045). POAF was divided into 29 temporary and 20 non-temporary types. The onset date of non-temporary-type POAF was significantly later than that of the transient type (P < 0.01), and diabetes mellitus was significantly higher in non-temporary-type POAF. Non-temporary-type POAF had a significantly poorer prognosis in terms of overall survival (p = 0.005). Poor PS, COPD, history of PAF, and intraoperative blood transfusion were independent risk factors for POAF. Non-temporary-type POAF occurred significantly later than transient type and caused poorer prognosis after lobectomy for lung cancer.

Fragmented QRS complexes are associated with postoperative atrial fibrillation development after coronary artery bypass grafting surgery.

Postoperative atrial fibrillation (PoAF) is one of the most frequent complications and a major risk factor of morbidity and mortality after coronary artery bypass grafting (CABG). Fragmented QRS complex (fQRS) on a 12-lead surface ECG is recently gained increasing attention as a simplified noninvasive ECG marker with diagnostic and prognostic value in various cardiac conditions. The aim of the present study was to evaluate the association between development of PoAF and presence of fQRS on admission ECG in patients undergoing CABG surgery. A total of 242 patients who underwent CABG between February 2016 and June 2018 were included in this study. The patients were divided into two groups as developing and nondeveloping PoAF groups in the postoperative period. fQRS was defined as the presence of various RSR' patterns including an additional R wave, notching of the R or S waves, or the presence of more than one fragmentation in two contiguous leads. In-hospital mortality was higher in PoAF (+) group compared to PoAF (-) group (20.5 vs. 6.4%, P = 0.004). PoAF rate was higher in fQRS (+) group than fQRS (-) group (25.3 vs. 9.8%, P = 0.001). In multivariate analysis, the presence of fQRS complexes on admission ECG [odds ratio (OR) 2.801, 95% confidence interval (CI) 1.262-6.211, P = 0.011) and hemoglobin (OR 0.794; 95% CI, 0.641-0.985; P = 0.036) were identified as independent predictors of PoAF after CABG surgery. The presence of fQRS on admission ECG was found to be an independent predictor of PoAF in patients undergoing isolated CABG.

Preoperative CHA2DS2-VASc Score Predicts Postoperative Atrial Fibrillation after Lobectomy.

Postoperative atrial fibrillation (POAF) affects 10 to 20% of noncardiac thoracic surgeries and increases patient morbidity and costs. The purpose of this study is to determine if preoperative CHA2DS2-VASc score can predict POAF after pulmonary lobectomy for nonsmall cell lung cancer. Patients with complete CHA2DS2-VASc data who underwent lobectomies from January 2007 to January 2016 at a single institution were analyzed in a retrospective case-control study using a prospective database. An independent samples t-test was used to compare the mean CHA2DS2-VASc scores of POAF and non-POAF groups. A multivariable logistic regression analysis (MVA) evaluated the independent contribution of variables of the CHA2DS2-VASc score in predicting POAF. Chi-square test with univariate odds ratios (ORs) was used to determine a statistically significant cutoff score for predicting POAF. Of 525 total patients, 82 (15.6%) developed POAF (mean CHA2DS2-VASc score: 2.7) and 443 (84.4%) did not develop POAF (mean score: 2.3). Mean difference between these groups was significant at 0.43 (p = 0.01; 95% confidence interval [CI]: 0.09-0.76). In the MVA, significant predictors of POAF were age 65 to 74 years (adjusted OR [aOR] = 2.45; 95% CI: 1.31-4.70; p = 0.006) and age ≥75 years (aOR = 3.11; 95% CI: 1.62-5.95; p = 0.0006). Patients with CHA2DS2-VASc scores ≥5 had significantly increased OR for POAF (OR = 2.59; 95% CI: 1.22-5.50). Preoperatively calculated CHA2DS2-VASc score can predict POAF in patients undergoing pulmonary lobectomy. Age is the most statistically significant independent predictor, and patients with scores ≥5 have significantly increased risk. Trials for POAF prophylaxis should target this population.

Clinical Risk Factors for Postoperative Atrial Fibrillation among Patients after Cardiac Surgery.

Postoperative atrial fibrillation (POAF) is a common arrhythmia following cardiac surgery and is associated with increased health-care costs, complications, and mortality. The etiology of POAF is incompletely understood and its prediction remains suboptimal. Using data from published studies, we performed a systemic review and meta-analysis to identify preoperative clinical risk factors associated with patients at increased risk of POAF. A systematic search of PubMed, MEDLINE, and EMBASE databases was performed. Twenty-four studies that reported univariate analysis results regarding POAF risk factors, published from 2001 to May 2017, were included in this meta-analysis with a total number of 36,834 subjects. Eighteen studies were performed in the United States and Europe and 16 studies were prospective cohort studies. The standardized mean difference (SMD) between POAF and non-POAF groups was significantly different (reported as [SMD: 95% confidence interval, CI]) for age (0.55: 0.47-0.63), left atrial diameter (0.45: 0.15-0.75), and left ventricular ejection fraction (0.30: 0.14-0.47). The pooled odds ratios (ORs) (reported as [OR: 95% CI]) demonstrated that heart failure (1.56: 1.31-1.96), chronic obstructive pulmonary disease (1.36: 1.13-1.64), hypertension (1.29: 1.12-1.48), and myocardial infarction (1.18: 1.05-1.34) were significant predictors of POAF incidence, while diabetes was marginally significant (1.06: 1.00-1.13). The present analysis suggested that older age and history of heart failure were significant risk factors for POAF consistently whether the included studies were prospective or retrospective datasets.

Relationship between red cell distribution width and mean platelet volume with new onset atrial fibrillation afteroff-pump coronary artery bypass grafting.

The aim of this study was to evaluate the relationship between red blood cell distribution width (RDW) and mean platelet volume (MPV) with development of postoperative atrial fibrillation (PoAF) after off-pump coronary artery bypass grafting (CABG). The RDW and MPV have been associated with some cardiovascular disorders. A total of 93 patients who underwent off-pump CABG were included in this study. The patients were divided into two groups as developing and nondeveloping PoAF groups in the postoperative period. We measured whether RDW and MPV levels are a predictive value for development PoAF. There were 24 patients with PoAF enrolled (mean age: 66 ± 7.8 years) and 69 patients without PoAF (mean age: 56.26 ± 11.53 years). The PoAF was significantly correlated with age (p = 0.004), hematocrit (p: 0.010), RDW (p = 0.007) and creatinine (p = 0.006). Only advanced age (p = 0.012) was identified as an independent predictor of PoAF. For predicting PoAF, there was 79.2 % sensitivity and 65.2 % specificity for RDW (p = 0.001) and 62.5 % sensitivity and 55.1 % specificity for MPV (p = 0.062). We found that RDW levels and MPV were not an independent predictor of the development of PoAF. However, elevated RDW levels and MPV may be one of the predictive values for PoAF development (Tab. 3, Fig. 2, Ref. 27).

Pre- and postoperative atrial fibrillation in CABG patients have similar prognostic impact

Objectives. To study pre- and postoperative atrial fibrillation and its long-term effects in a cohort of aortocoronary bypass surgery patients. Design. Altogether 615 patients undergoing aortocoronary bypass graft surgery in 1999–2000 were studied. Forty-four (7%) had preoperative atrial fibrillation. Postoperative atrial fibrillation occurred in 165/615 patients (27%) while 406/615 patients (66%) had no atrial fibrillation. After a median follow-up of 15 years, symptoms and medication in survivors were recorded, and cause of death in the deceased was obtained. Results. Death due to cerebral ischaemia was most common in the pre- and postoperative atrial fibrillation groups (7% and 5%, respectively, v. 2% among those without atrial fibrillation, p = .038), as were death due to heart failure (18% and 14%, v. 7%, p = .007) and sudden death (9% and 5%, v. 2%, p = .029). The presence of pre- or postoperative atrial fibrillation was an independent risk factor for late mortality (hazard ratios 1.47 (1.02–2.12) and 1.28 (1.01–1.63), respectively). Conclusions. Patients with pre- or postoperative atrial fibrillation undergoing aortocoronary bypass surgery have increased long-term mortality and risk of cerebral ischemic and cardiovascular death compared with patients in sinus rhythm.

Plasma 25-hydroxyvitamin D2 and D3 levels and incidence of postoperative atrial fibrillation.

Low circulating levels of total 25-hydroxyvitamin D (25(OH)D) have been associated with an increased risk of adverse effects after cardiac surgery. The metabolites, 25(OH)D2 and 25(OH)D3, provide a good index of vitamin D status. In this study, we examined the association between preoperative plasma levels of total 25(OH)D, 25(OH)D2 and 25(OH)D3 and the risk of postoperative atrial fibrillation (POAF) following open heart surgery. The levels of plasma 25(OH)D2 and 25(OH)D3 in 118 patients, who underwent coronary artery bypass grafting and/or valvular surgery, were measured immediately prior to surgery and on postoperative day 3 by liquid chromatography-tandem mass spectrometry. Patients who developed POAF had higher median plasma levels of 25(OH)D2 than those who remained in sinus rhythm (SR) (P=0·003), but no significant difference was noted in levels of 25(OH)D3 or total 25(OH)D between the two groups (P>0·05). By univariate analysis, patients with total 25(OH)D and 25(OH)D2 levels above the median had higher frequency of POAF (P<0·05) and the incidence of POAF increased significantly with each higher quartile of preoperative plasma levels of 25(OH)D2 (P=0·001), an association that was independent of confounding factors. In both the SR and POAF groups, the median plasma levels of 25(OH)D2, 25(OH)D3 and total 25(OH)D were lower (P<0·05) on the third postoperative day compared with preoperatively. Our findings demonstrate that higher plasma levels of 25(OH)D2 are associated with increased risk of POAF, while this is not the case for 25(OH)D3 or total 25(OH)D. The reason for these discrepant results is not clear but warrants further study.

Clinical and histological predictive risk factors of atrial fibrillation in patients undergoing open-heart surgery.

Postoperative atrial fibrillation (POAF) is a common complication subsequent to cardiac surgery. Various risk factors have been reported for the development of this complication; however, their precise role in POAF is unknown. In the present study, we attempted to identify clinical factors and histopathological changes in atrial tissue that may predict the development of POAF. Atrial tissue was sampled from 103 patients in sinus rhythm that had undergone open-heart surgery, including elective coronary artery bypass grafting (79.61%) and heart valve surgery (20.38%). Atrial surgical biopsies were obtained from the right atrial appendage at the site of cannulation, prior to cardiopulmonary bypass. Tissues were processed routinely for light microscopy, then stained with hematoxylin and eosin and sirius red. Microscopical exams were used to observe the atrial lesions and morphometry was conducted for quantification. In total, 37 patients (35.92%) developed POAF and atrial lesions were identified in the majority of patients in the normal postoperative sinus rhythm and POAF groups, but were most common in the POAF patients. The most common risk factors involved in developing POAF were found to be: Age of >60 years, male gender, ejection fraction of <50% and increased pulmonary hypertension. Furthermore, interstitial fibrosis and myocytolysis were the most common injuries identified. Abnormalities in atrial surgical biopsies may indicate the susceptibility of a patient to developing POAF. The present results suggest that the pre-existent alterations in the structure of the right atrium may be a major determinant in the development of POAF.

New-onset atrial fibrillation following coronary bypass surgery predicts long-term mortality: a systematic review and meta-analysis.

Atrial fibrillation (AF) is one of the most common postoperative complications following cardiac surgery. Recent evidence suggests that postoperative atrial fibrillation (POAF) may be more 'malignant' than previously thought, associated with follow-up mortality and morbidity. To evaluate the long-term survival of POAF versus No-POAF cohorts following coronary bypass surgery, the current meta-analysis with reconstructed individual patient data was performed. Electronic searches were performed using six databases from their inception to August 2014. Relevant studies with long-term survival data presented for POAF versus No-POAF were identified. Data were extracted by two independent reviewers and analysed according to predefined clinical endpoints. The pooled hazard ratio (HR) significantly favoured higher survival in No-POAF over POAF (HR 1.28; 95% CI, 1.19-1.37; I(2) = 96%; P < 0.00001). Individual patient data of 69 518 patients were available for inverted Kaplan-Meier survival curve analysis. Analysis of aggregate data using Kaplan-Meier curve methods for POAF versus No-POAF groups determined survival rates at the 1-year (95.7 vs 98%), 2-year (92.3 vs 95.4%), 3-year (88.7 vs 93.9%), 5-year (82.6 vs 89.4%) and 10-year (65.5 vs 75.3%) follow-up. Other complications including 30-day mortality, strokes, respiratory failure, pneumonia and hospitalization were significantly higher in the POAF group. New-onset AF following coronary bypass surgery is associated with significantly higher risk of mortality in short- and long-term follow-up. Current evidence suggests the need for stricter surveillance and monitoring of POAF following coronary bypass surgery.

POSTOPERATIVE ATRIAL FIBRILLATION IS ASSOCIATED WITH HIGHER EUROSCORE, BUT NOT WITH HOSPITAL MORTALITY AFTER CORONARY ARTERY BYPASS GRAFT SURGERY

Background: Postoperative atrial fibrillation (POAF) is the most common arrhythmia after coronary artery bypass surgery (CABG) and is associated with an increased morbidity. Recently, it has been suggested that POAF is also associated with increased postoperative mortality. Aim: To investigate whether POAF after isolated CABG was associated with a higher EuroSCORE, indicating greater in-hospital mortality risk. Methods: We reviewed data from our prospective cardiac surgery database of all patients (n=2791) undergoing isolated CABG from January 2003 through December 2006 at a large university medical center. The Mann-Whitney test was used to test for differences in continuous variables between the POAF and non-POAF groups, while the Chi-square test was used for categorical variables. Cox proportional-hazards regression analysis was used to identify independent predictors of in-hospital mortality. Results: The mean age was 68 ± 9.1yrs, and mean EuroSCORE was 6.91 ± 3.18. The overall incidence of POAF was 32.3%. The POAF group was older (70.5 ± 7.8 vs. 66.8 ± 9.5yrs non-POAF: p<0.0001), but there was no significant difference in ejection fraction (EF) between the two groups (p=0.13). There was a significant difference in the mean EuroSCORE (POAF, 7.6 ± 3.2 vs non-POAF, 6.6 ± 3.1, p<0.0001), indicating that the POAF group was at greater risk for postoperative mortality. Although, there was a significant association between EuroSCORE and POAF (p<0.0001), there was no significant difference in hospital mortality between the POAF and non-POAF groups. The overall hospital mortality was 1.9%, with no difference between the two groups (p=0.91). Furthermore, POAF was not predictive of hospital mortality after CABG. Conclusion: POAF is associated with a higher EuroSCORE, but it is neither associated with, nor predictive of increased hospital mortality after CABG.

Postoperative Atrial Fibrillation After Isolated Aortic Valve Replacement: A Cause for Concern?

Several studies have shown that postoperative atrial fibrillation (POAF) is associated with poorer short-term and long-term outcomes after general cardiac operations. There is, however, a paucity of data on the impact of POAF on outcomes after isolated aortic valve replacement (AVR). Data for all patients undergoing isolated first-time AVR between June 2001 and December 2009 was obtained from the Australasian Society of Cardiac and Thoracic Surgeons (ASCTS) National Cardiac Surgery Database Program and a retrospective analysis was conducted. Preoperative characteristics, early postoperative outcome, and late survival were compared between patients in whom POAF developed and those in whom it did not. Propensity score matching was performed to correct for differences between the 2 groups. Excluding patients with preoperative arrhythmia, isolated first-time AVR was performed in 2,065 patients. POAF developed in 725 (35.1%) of them. Patients with POAF were significantly older (mean age, 72 versus 65 years; p < 0.001) and presented more often with comorbidities, including hypertension, respiratory disease, and hypercholesterolemia (all p < 0.05). From the initial study population, 592 propensity-matched patient pairs were derived; the overall matching rate was 81.7%. In the matched groups, 30-day mortality was not significantly different between the POAF and non-POAF groups (1.5% versus 1%; p = 0.48). Patients with POAF were, however, at an independently increased risk of perioperative complications, including new renal failure, gastrointestinal complications, and 30-day readmission (p < 0.05). Seven-year mortality was not significantly different between POAF and non-POAF groups (78% versus 83%; p = 0.63). POAF is a risk factor for short-term morbidity but is not associated with a higher rate of early or late mortality after isolated AVR.

Postoperative Atrial Fibrillation is Associated with Higher Euroscore, but not with Hospital Mortality after Coronary Artery Bypass Graft Surgery

Background: Postoperative atrial fibrillation (POAF) is the most common arrhythmia after coronary artery bypass surgery (CABG) and is associated with an increased morbidity. Recently, it has been suggested that POAF is also associated with increased postoperative mortality. Aim: To investigate whether POAF after isolated CABG was associated with a higher EuroSCORE, indicating greater in-hospital mortality risk. Methods: We reviewed data from our prospective cardiac surgery database of all patients (n=2791) undergoing isolated CABG from January 2003 through December 2006 at a large university medical center. The Mann-Whitney test was used to test for differences in continuous variables between the POAF and non-POAF groups, while the Chi-square test was used for categorical variables. Cox proportional-hazards regression analysis was used to identify independent predictors of in-hospital mortality. Results: The mean age was 68 ± 9.1yrs, and mean EuroSCORE was 6.91 ± 3.18. The overall incidence of POAF was 32.3%. The POAF group was older (70.5 ± 7.8 vs. 66.8 ± 9.5yrs non-POAF: p<0.0001), but there was no significant difference in ejection fraction (EF) between the two groups (p=0.13). There was a significant difference in the mean EuroSCORE (POAF, 7.6 ± 3.2 vs non-POAF, 6.6 ± 3.1, p<0.0001), indicating that the POAF group was at greater risk for postoperative mortality. Although, there was a significant association between EuroSCORE and POAF (p<0.0001), there was no significant difference in hospital mortality between the POAF and non-POAF groups. The overall hospital mortality was 1.9%, with no difference between the two groups (p=0.91). Furthermore, POAF was not predictive of hospital mortality after CABG. Conclusion: POAF is associated with a higher EuroSCORE, but it is neither associated with, nor predictive of increased hospital mortality after CABG