Aging and atrial fibrillation research: where we are and where we should go

Determinants of supraventricular extra beats in elite athletes practicing different sporting disciplines

BACKGROUND

Supraventricular extra beats (SVEB) are frequently observed in athletes but data on significance, prognostic role and correlation with cardiac remodeling are contrasting. It is uncertain whether SVEB may indicate the development of more complex arrhythmias and the need for closer monitoring is undetermined. The aim was to assess the prevalence and clinical significance of BESV in Olympic athletes of different sporting disciplines, evaluating potential correlations with cardiac remodeling and clinical features.

METHODS

We enrolled athletes who participated at 2012-2022 Olympic Games, submitted to physical examination, blood tests, echocardiography and exercise tests, categorized into power, skills, endurance and mixed disciplines.

RESULTS

We studied 1492 elite athletes: 56% male individuals, mean age 25.8 ± 5.1 years; 29.5% practiced power, 12.3% skills, 21% endurance and 37.2% mixed disciplines. At exercise-stress tests, 6.2% had SVEB, mostly single beats. SVEB were not influenced by anthropometrics or blood test results. They were more common in male individuals (77.4 vs. 54.6%, P < 0.0001) and older athletes (27.1 ± 5.7 vs. 25.7 ± 5.1, P = 0.01). In male athletes with SVEB, higher left atrial volumes were observed (24.2 ± 7.3 vs. 22.2 ± 7.1 ml/m2, P = 0.03). No differences were found in terms of sporting discipline: despite larger left atrial dimensions in aerobic disciplines, SVEB rates were similar in different sporting disciplines (6.1% endurance, 6.3% mixed, 5.2% power and 8.7% skills; P = 0.435).

CONCLUSION

SVEB were more common in older, male athletes and associated with higher left atrial volume (especially in male individuals) regardless of sport practiced. Athletes with greater left atrial volume and SVEB are supposed to have higher risk, in middle age, of developing more complex arrhythmias.

Risk of atrial fibrillation in patients with systemic sclerosis: a nationwide population-based study

OBJECTIVE

Atrial fibrillation (AF) is the most common arrhythmia in the general population, causing substantial economic burden, morbidity and mortality. The incidence rate and risk of AF in patients with SSc are unclear. We aimed to assess the incidence rate of AF in patients with SSc and the risk of incident AF in patients with SSc compared with the general population.

METHODS

The Korean National Health Insurance Service database was used as the data source. Patients with claims data for SSc between 2010 and 2017 were extracted from the database along with 1:5 age- and sex-matched controls. The index date was the earliest date with claims data for SSc between 2010 and 2017. The follow-up duration was from the index date to 2019. Multivariable Cox proportional hazard models were used to estimate the hazard ratio (HR) and 95% CI for AF in patients with SSc.

RESULTS

Overall, 2519 patients with SSc and 12 595 age- and sex-matched controls were included. Over a mean follow-up duration of 5.2 years (s.d. 2.6), the incidence rates of AF were 3.52 and 1.68 per 1000 person-years for patients with SSc and controls, respectively. Compared with controls, patients with SSc had a significantly higher risk of incident AF [adjusted HR 2.095 (95% CI 1.466, 2.994)].

CONCLUSION

Patients with SSc had a 2-fold higher risk of incident AF than controls. Given the significant economic burden, morbidity and mortality that AF poses, close monitoring for incident AF in patients with SSc is warranted.

Cryoballoon ablation of atrial fibrillation in octogenarians: one year outcomes from the cryo global registry

BACKGROUND

Limited information is available on the safety and efficacy of cryoballoon ablation (CBA) in elderly patients with atrial fibrillation (AF). Moreover, global utilization of CBA in this population (≥ 80 years old) has not been reported. This study's objectives were to determine the use, efficacy, and safety of CBA to treat octogenarians suffering from AF.

METHODS

In this sub-analysis of the Cryo Global Registry, 12-month outcomes of treating AF via CBA in octogenarians were compared to patients < 80 years old. Efficacy was evaluated as time to a ≥ 30 s atrial arrhythmia (AA) recurrence. Healthcare utilization was determined via repeat ablations and hospitalizations. Improvement upon disease burden was evaluated through patient reporting of symptoms and the EQ-5D-3L quality of life (QoL) survey.

RESULTS

The octogenarian cohort (n = 101) had a higher prevalence of females (51.5% vs 35.7%) and CHA2DS2-VASc scores (4.2 ± 1.3 vs 2.0 ± 1.5) compared to the control cohort (n = 1573, both p < 0.01). Even when adjusting for baseline characteristics and antiarrhythmic drug usage, freedom from AA recurrence at 12 months (80.6% vs 78.9%, HRadj:0.97 [95% CI:0.59-1.58], p = 0.90) was comparable between octogenarians and control, respectively. Similar serious adverse event rates were observed between octogenarians (5.0%) and control (3.2%, p = 0.38). The groups did not differ in healthcare utilization nor reduction of AF-related symptoms from baseline to follow-up, but both experienced an improvement in QoL at 12 months.

CONCLUSIONS

Despite more age-related comorbidities, CBA is a safe and effective treatment for AF in octogenarians, with efficacy and adverse events rates akin to ablations performed in younger patients.

CLINICAL TRIAL REGISTRATION

https://clinicaltrials.gov/ct2/show/NCT02752737.

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

Background

Postoperative atrial fibrillation (AF) has a complex etiology, and beta-blockers are commonly recommended for its pharmacological prevention. This study aims to assess the impact of beta-blocker therapy on postoperative AF occurrence in patients undergoing aortic valve replacement, mitral valve replacement, surgical revascularization of the myocardium, or a combination of these procedures.

Methods

The study encompassed 472 patients who received aortic valve replacement, mitral valve replacement, surgical revascularization, or their combination. We evaluated the efficacy of preoperative and one-month postoperative beta-blocker administration in preventing postoperative AF, and the associated risk factors involved in the development of postoperative AF.

Results

Of the total patient population, 36% experienced postoperative AF. Our study demonstrated a significant reduction in postoperative AF incidence among patients receiving beta-blocker treatment (all p-values < 0.05). Additionally, one-month post-surgery, beta-blocker treatment exerted a protective effect by maintaining the sinus rhythm (p = 0.0001). Regarding the risk factors involved in the development of postoperative AF, both age and left atrium (LA) sizeassessed pre-and postoperatively-were positively correlated with the occurrence of postoperative AF (p = 0.006). No relationship was found between leukocyte counts and AF incidence. Notably, C-reactive protein (CRP) levels were significantly elevated on the fifth postoperative day in patients with AF (p < 0.007). The duration of ischemia was significantly longer in patients with AF (p = 0.009).

Conclusions

This study establishes the efficacy of perioperative beta-blocker treatment in mitigating postoperative AF. One month post-surgery, most patients under beta-blocker therapy maintained sinus rhythm, suggesting a potential long-term protective effect of beta-blockers against late-onset AF.

Development and validation of a nomogram for predicting atrial fibrillation in patients with acute heart failure admitted to the ICU: a retrospective cohort study

INTRODUCTION

Acute heart failure is a serious condition. Atrial fibrillation is the most frequent arrhythmia in patients with acute heart failure. The occurrence of atrial fibrillation in heart failure patients worsens their prognosis and leads to a substantial increase in treatment costs. There is no tool that can effectively predict the onset of atrial fibrillation in patients with acute heart failure in the ICU currently.

MATERIALS AND METHODS

We retrospectively analyzed the MIMIC-IV database of patients admitted to the intensive care unit (ICU) for acute heart failure and who were initially sinus rhythm. Data on demographics, comorbidities, laboratory findings, vital signs, and treatment were extracted. The cohort was divided into a training set and a validation set. Variables selected by LASSO regression and multivariate logistic regression in the training set were used to develop a model for predicting the occurrence of atrial fibrillation in acute heart failure in the ICU. A nomogram was drawn and an online calculator was developed. The discrimination and calibration of the model was evaluated. The performance of the model was tested using the validation set.

RESULTS

This study included 2342 patients with acute heart failure, 646 of whom developed atrial fibrillation during their ICU stay. Using LASSO and multiple logistic regression, we selected six significant variables: age, prothrombin time, heart rate, use of vasoactive drugs within 24 h, Sequential Organ Failure Assessment (SOFA) score, and Acute Physiology Score (APS) III. The C-index of the model was 0.700 (95% CI 0.672-0.727) and 0.682 (95% CI 0.639-0.725) in the training and validation sets, respectively. The calibration curves also performed well in both sets.

CONCLUSION

We developed a simple and effective model for predicting atrial fibrillation in patients with acute heart failure in the ICU.

Identification of atrial fibrillation drivers by means of concentric ring electrodes

BACKGROUND AND OBJECTIVE

The prevalence of atrial fibrillation (AF) has tripled in the last 50 years due to population aging. High-frequency (DFdriver) activated atrial regions lead the activation of the rest of the atria, disrupting the propagation wavefront. Fourier based spectral analysis of body surface potential maps have been proposed for DFdriver identification, although these approaches present serious drawbacks due to their limited spectral resolution for short AF epochs and the blurring effect of the volume conductor. Laplacian signals (BC-ECG) from bipolar concentric ring electrodes (CRE) have been shown to outperform the spatial resolution achieved with conventional unipolar recordings. Our aimed was to determine the best DFdriver estimator in endocardial electrograms and to assess the BC-ECG capacity of CRE to quantify AF activity non-invasively.

METHODS

31 AF episodes were simulated using realistic tridimensional models of the atria electrical activity and torso. Periodogram and autoregressive (AR) spectral estimators were computed and the percentile (P90^th, P95^th and P98^th) to impose on the dominant frequencies (DFs) across whole atria to define the best DFdriver estimator evaluated. The identification of DFdriver on DFs from BC-ECG and unipolar surface signals with conventional disc electrodes was compared.

RESULTS

The best DFdriver estimator was P95^th and AR order 100. BC-ECG signals allowed better detection of AF activity than unipolar signals, with a significantly greater percentage of electrode locations in which DFdriver was identified (p-value 0.0095).

CONCLUSIONS

The use of BC-ECG signals for body surface Laplacian potential mapping with CRE could be helpful for better AF diagnosis, prognosis and ablation procedures than those with conventional disk electrodes.

Risk of dementia in patients with atrial fibrillation: Short versus long follow-up. A systematic review and meta-analysis

BACKGROUND

No previous meta-analyses have compared the risk of dementia, due to an underlying atrial fibrillation (AF), in the short-term versus the long-term period.

AIM

To perform an update meta-analysis of studies examining the association between AF and dementia and the relative impact of follow-up period.

METHODS

Data were obtained searching MEDLINE and Scopus for all investigations published between 1 January 2000 and March 1, 2021 reporting the risk of dementia in AF patients. The following MeSH terms were used for the search: "Atrial Fibrillation" AND "Dementia" OR "Alzheimer's disease". From each study, the adjusted hazard ratio (aHR) with the related 95% confidence interval (CI) was pooled using a random effect model.

RESULTS

The analysis was carried out on 18 studies involving 3.559.349 subjects, of which 902.741 (25.3%) developed dementia during follow-up. A random effect model revealed an aHR of 1.40 (95% CI: 1.27-1.54, p < 0.0001; I2  = 93.5%) for dementia in subjects with AF. Stratifying the studies according to follow-up duration, those having a follow-up ≥10 years showed an aHR for dementia of 1.37 (95% CI: 1.21-1.55, p < 0.0001, I2  = 96.6%), while those with a follow-up duration <10 years has a slightly higher aHR for dementia (HR: 1.59, 95%CI: 1.51-1.67, p < 0.0001, I2  = 49%). Nine studies showed that the aHR for Alzheimer's disease (AD) in AF patients was 1.30 (95%CI: 1.12-1.51, p < 0.0001, I2  = 87.6%).

CONCLUSIONS

Evidence suggests that patients with AF have an increased risk of developing dementia and AD. The risk of dementia was slightly higher when the follow-up was shorter than 10 years.

Utility of the CHA2DS2-VASc Score in Prediction of Postoperative Atrial Fibrillation After Coronary Artery Bypass Graft Surgery

OBJECTIVE

The authors aimed to investigate the role of CHA₂DS₂-VASc score and its components in prediction of postoperative atrial fibrillation (POAF) after isolated coronary artery bypass graft (CABG) surgery.

DESIGN

Retrospective cohort.

SETTING

Single-center university-affiliated tertiary cardiac center.

PARTICIPANTS

A total of 2,981 consecutive patients who underwent isolated CABG between 2010 and 2012 were included.

INTERVENTIONS

All patients underwent isolated CABG and were followed until discharge or in-hospital death. The primary outcome was the development of new-onset POAF during the hospital course.

MEASUREMENTS AND MAIN RESULTS

During hospitalization, continuous electrocardiogram monitoring was used to detect POAF episodes. New-onset POAF developed in 15.8% of patients following isolated CABG. Patients with POAF had significantly higher CHA₂DS₂-VASc scores than those without POAF (2.66 ± 1.51 v 2.12 ± 1.36, p < 0.001). After adjustment for potential confounders, CHA₂DS₂-VASc score was significantly associated with POAF (odds ratio [OR]: 1.295, 95% CI: 1.205-1.391). However, further analyses showed that this effect was restricted to patients with a CHA₂DS₂-VASc score of ≥2 (OR: 1.813, 95% CI: 1.220-2.694). In multivariate analysis of the CHA₂DS₂-VASc components, age ≥75 (OR: 3.737, 95% CI: 2.702-5.168), age 65 to 74 (OR: 2.126, 1.701-2.658), hypertension (OR: 1.310, 95% CI: 1.051-1.633), and cerebrovascular accident (OR: 1.807, 95% CI: 1.197-2.726) were independent predictors of POAF. However, the association between POAF and female sex, diabetes mellitus, congestive heart failure, and vascular disease was not statistically significant.

CONCLUSIONS

CHA₂DS₂-VASc score is a useful tool for the prediction of POAF after isolated CABG. However, the risk should be interpreted cautiously, since the risk score's promising effect relies on only several of its components.

Risk factors for recurrence of atrial fibrillation

OBJECTIVE

Atrial fibrillation (AF) is a progressive disease, associated with increased risk of mortality, stroke, heart failure, and worsens quality of life. There is a high incidence of AF recurrence despite the treatment. The aim of the study was to assess the time to recurrence of AF after sinus rhythm restoration with electrical or pharmacological cardioversion and to identify the risk factors.

METHODS

This study included 101 patients with AF (56% females) at a mean age of 68.02±7 years, after sinus rhythm restoration in a clinical observation of 1-year placebo-controlled treatment with spironolactone (1: 1). The patients were analyzed on the basis of AF recurrence, hospitalization, demographic parameters, comorbidities, embolic risk, and value of biomarker galectin-3 (Gal-3).

RESULTS

The average number of AF recurrences was1.62 per patient per year. The median time of occurrence of at least one new episode was 48 days, 95% confidence interval (CI) 14.24-81.76. Female patients experienced significantly more recurrences than male-53.3% vs. 28.6% hazard ration (HR) =1.76, 95% CI 1.02-3.03, p=0.036. The recurrences were more common with increased age, although not significantly. Patients with arterial hypertension had a threefold risk of recurrences than those without hypertension (p=0.025), independently of the treatment. CHA2DS2-VASc score was significantly associated with AF recurrent episodes. Patients with gout had a twofold increased risk, without statistical significance (p=0.15). There was no difference in the AF episodes according to treatment with spironolactone. The levels of Gal-3 did not affect the number of AF recurrences (p=0.9).

CONCLUSION

AF is associated with frequent recurrences after restoration of sinus rhythm in the majority of the patients. Most of them occurred within the first 3 months. Female sex, arterial hypertension, and CHA2DS2-VASc score were significant predictors of AF recurrence. Spironolactone did not reduce AF recurrences.

Burden of premature atrial beats in middle-aged endurance athletes with and without lone atrial fibrillation versus sedentary controls

BACKGROUND

The burden of premature atrial beats (PABs) at 24-h electrocardiographic (ECG) monitoring correlates with the risk of atrial fibrillation. It is unknown whether prolonged and intense exercise increases the burden of PABs, thus contributing to the higher prevalence of atrial fibrillation observed in middle-aged athletes.

METHODS

We compared the burden of PABs at 24-h ECG monitoring off therapy in 134 healthy middle-aged (30-60-year-old) competitive athletes who had practised 9 (7-11) h of endurance sports for 8 (4-15) consecutive years, 134 age- and gender-matched healthy sedentary individuals, and 66 middle-aged patients (20 athletes and 46 non-athletes) with 'lone' paroxysmal atrial fibrillation.

RESULTS

More than 50 PABs/24 h or ≥1 run of ≥3 PABs were recorded in 23/134 (17%) healthy athletes and in 29/134 (22%) sedentary controls (p = 0.61). Healthy athletes with frequent or repetitive PABs were older (median 50 years vs. 43 years, p < 0.01) and had practised sport for a longer time (median 10 years vs. 6 years, p = 0.03). At multivariable analysis only age (odds ratio 1.11, 95% confidence interval 1.04-1.20, p < 0.01) remained an independent predictor of a higher burden of PABs. Also among patients with 'lone' paroxysmal atrial fibrillation, there was no difference in the prevalence of >50 PABs/24 h or ≥1 run of ≥3 PABs between athletes (40%) and controls (48%, p = 0.74).

CONCLUSIONS

Middle-aged endurance athletes, with or without paroxysmal atrial fibrillation, did not show a higher burden of PABs at 24-h ECG monitoring than sedentary controls. Age, but not intensity and duration of sports activity, predicted a higher burden of PABs among healthy athletes.

Atrial Fibrillation in Older People: Concepts and Controversies

Atrial fibrillation (AF) is the commonest cardiac rhythm abnormality and has a significant disease burden. Amongst its devastating complications is stroke, the risk of which increases with age. The stroke risk in an older person with AF is therefore tremendous, and oral-anticoagulation (OAC) therapy is central to minimizing this risk. The presence of age-associated factors such as frailty and multi-morbidities add complexity to OAC prescription decisions in older patients and often, OAC is needlessly withheld from them despite a lack of evidence to support this practice. Generally, this is driven by an over-estimation of the bleeding risk. This review article provides an overview of the concepts and controversies in managing AF in older people, with respect to the existing evidence and current practice. A literature search was conducted on Pubmed and Cochrane using keywords, and relevant articles published by the 1st of May 2019 were included. The article will shed light on common misconceptions that appear to serve as rationale for precluding OAC and focus on clinical considerations that may aid OAC prescription decisions where appropriate, to optimize AF management using an integrated, multi-disciplinary care approach. This is crucial for all patients, particularly older individuals who are most vulnerable to the deleterious consequences of this condition.

Association of lipoprotein-associated phospholipase A2 and risk of incident atrial fibrillation: Findings from 3 cohorts

BACKGROUND

Multiple prospective studies have established an association between inflammation and higher risk of atrial fibrillation (AF), but the association between lipoprotein-associated phospholipase A2 (Lp-PLA2) mass and activity and incident AF has not been extensively evaluated.

METHODS

Using data from 10,794 Atherosclerosis Risk In Communities (ARIC) study participants aged 53-75 years, 5,181 Cardiovascular Health Study (CHS) participants aged 65 to 100 years, and 5,425 Multi-Ethnic Study of Atherosclerosis (MESA) participants aged 45-84 years, we investigated the association between baseline Lp-PLA2 levels and the risk of developing AF. Incident AF was identified in each cohort by follow-up visit electrocardiograms, hospital discharge coding of AF, or Medicare claims data.

RESULTS

Over a mean of 13.1, 11.5, and 10.0 years of follow-up, 1,439 (13%), 2,084 (40%), and 615 (11%) incident AF events occurred in ARIC, CHS, and MESA, respectively. In adjusted analyses, each SD increment in Lp-PLA2 activity was associated with incident AF in both ARIC (hazard ratio [HR] 1.13, 95% CI 1.06-1.20) and MESA (HR 1.24, 95% CI 1.05-1.46). Each SD increment in Lp-PLA2 mass was also associated with incident AF in MESA (HR 1.25, 95% CI 1.11-1.41). No significant associations were observed among CHS participants.

CONCLUSIONS

Although higher Lp-PLA2 mass and activity were associated with development of AF in ARIC and MESA, this relationship was not observed in CHS, a cohort of older individuals.

A retrospective study on atrial fibrillation after coronary artery bypass grafting surgery at The National Heart Institute, Kuala Lumpur

Background: Atrial fibrillation (AF) is common after cardiac surgery and has been associated with poor outcome and increased resource utilization. The main objective of this study is to determine the incidence of POAF in Malaysia and identify the predictors of developing POAF. The secondary outcome of this study would be to investigate the difference in mortality and morbidity rates and the duration of intensive care unit (ICU), high dependency unit (HDU) and hospital stay between the two. Methods: This is a retrospective single-center, cross sectional study conducted at the National Heart Institute, Malaysia. Medical records of 637 who underwent coronary artery bypass grafting (CABG) surgery in 2015 were accrued. Pre-operative, operative and post-operative information were subsequently collected on a pre-formulated data collection sheet. Data were then analyzed using IBM SPSS v23. Results: The incidence of POAF in our study stands at 28.7% with a mean onset of 45±33 hours post operatively. Variables with independent association with POAF include advancing age, Indian population, history of chronic kidney disease, left ventricular ejection fraction and beta-blocker treatment. The mortality rate is significantly higher statistically ( p < 0.05), and similarly the incidence of stroke. The incidence of other post-operative complications was also significantly higher statistically. The duration of ICU, HDU and hospital stays were statistically longer ( p < 0.001) with higher rates of ICU readmissions and reintubations seen. Conclusion: We conclude that the incidence of POAF in Malaysia is comparable to the figures in Western countries, making POAF one of the most commonly encountered condition after CABG with similar higher rates of mortality, poor outcomes and longer duration of stay, and therefore increased cost of care. Strategies to reduce the incidence of AF after cardiac surgery should favorably affect surgical outcomes and reduce utilization of resources and thus lower cost of care.

A retrospective study on atrial fibrillation after coronary artery bypass grafting surgery at The National Heart Institute, Kuala Lumpur

Background: Atrial fibrillation (AF) is common after cardiac surgery and has been associated with poor outcome and increased resource utilization. The main objective of this study is to determine the incidence of POAF in Malaysia and identify the predictors of developing POAF. The secondary outcome of this study would be to investigate the difference in mortality and morbidity rates and the duration of intensive care unit (ICU), high dependency unit (HDU) and hospital stay between the two. Methods: This is a retrospective single-center, cross sectional study conducted at the National Heart Institute, Malaysia. Medical records of 637 who underwent coronary artery bypass grafting (CABG) surgery in 2015 were accrued. Pre-operative, operative and post-operative information were subsequently collected on a pre-formulated data collection sheet. Data were then analyzed using IBM SPSS v23. Results: The incidence of POAF in our study stands at 28.7% with a mean onset of 45±33 hours post operatively. Variables with independent association with POAF include advancing age, Indian population, history of chronic kidney disease, left ventricular ejection fraction and beta-blocker treatment. The mortality rate is significantly higher statistically ( p < 0.05), and similarly the incidence of stroke. The incidence of other post-operative complications was also significantly higher statistically. The duration of ICU, HDU and hospital stays were statistically longer ( p < 0.001) with higher rates of ICU readmissions and reintubations seen. Conclusion: We conclude that the incidence of POAF in Malaysia is comparable to the figures in Western countries, making POAF one of the most commonly encountered condition after CABG with similar higher rates of mortality, poor outcomes and longer duration of stay, and therefore increased cost of care. Strategies to reduce the incidence of AF after cardiac surgery should favorably affect surgical outcomes and reduce utilization of resources and thus lower cost of care.

Catheter Ablation Of Atrial Fibrillation In The Elderly: Risk Benefit Analysis

Over the past decade, catheter ablation has emerged as an important therapeutic option and reserved for drug refractory symptomatic paroxysmal and persistent atrial fibrillation (AF). Although elderly population constitutes the significant amount of AF patients, literature data is inadequate regarding the use of catheter ablation for elderly AF patients. Since there has been significant improvement in efficacy and safety of the AF ablation in last decade, it has become widespread accross the whole world. As the life expectancy continues to grow in population and outcomes of catheter ablation for AF further improve, higher number of elderly patients are likely to undergo catheter ablation for AF. Therefore, in this paper we reviewed the published literature to date regarding the clinical efficacy and safety of catheter ablation for AF in elderly patients.

The persistent problem of new-onset postoperative atrial fibrillation: a single-institution experience over two decades

OBJECTIVE

Postoperative atrial fibrillation is the most common complication after cardiac surgery. A variety of postoperative atrial fibrillation risk factors have been reported, but study results have been inconsistent or contradictory, particularly in patients with preexisting atrial fibrillation. The incidence of postoperative atrial fibrillation was evaluated in a group of 10,390 patients undergoing cardiac surgery among a comprehensive range of risk factors to identify reliable predictors of postoperative atrial fibrillation.

METHODS

This 20-year retrospective study examined the relationship between postoperative atrial fibrillation and demographic factors, preoperative health conditions and medications, operative procedures, and postoperative complications. Multivariate logistic regression models were used to evaluate potential predictors of postoperative atrial fibrillation.

RESULTS

Increasing age, mitral valve surgery (odds ratio=1.91), left ventricular aneurysm repair (odds ratio=1.57), aortic valve surgery (odds ratio=1.52), race (Caucasian) (odds ratio=1.51), use of cardioplegia (odds ratio=1.36), use of an intraaortic balloon pump (odds ratio=1.28), previous congestive heart failure (odds ratio=1.28), and hypertension (odds ratio=1.15) were significantly associated with postoperative atrial fibrillation. The non-linear relationship between age and postoperative atrial fibrillation revealed the acceleration of postoperative atrial fibrillation risk in patients aged 55 years or more. In patients undergoing coronary artery bypass grafting, increasing age and previous congestive heart failure were the only factors associated with a higher risk of postoperative atrial fibrillation. There was no trend in incidence of postoperative atrial fibrillation over time. No protective factors against postoperative atrial fibrillation were detected, including commonly prescribed categories of medications.

CONCLUSIONS

The persistence of the problem of postoperative atrial fibrillation and the modest predictability using common risk factors suggest that limited progress has been made in understanding its cause and treatment.