Anticoagulation in new-onset postoperative atrial fibrillation: An analysis from the Society of Thoracic Surgeons Adult Cardiac Surgery Database

Novel linkage of the Society of Thoracic Surgeons database and hospital electronic health records

BACKGROUND

Society of Thoracic Surgeons Congenital Heart Surgery Database is the largest congenital heart surgery database worldwide but does not provide information beyond primary episode of care. Linkage to hospital electronic health records would capture complications and comorbidities along with long-term outcomes for patients with CHD surgeries. The current study explores linkage success between Society of Thoracic Surgeons Congenital Heart Surgery Database and electronic health record data in North Carolina and Georgia.

METHODS

The Society of Thoracic Surgeons Congenital Heart Surgery Database was linked to hospital electronic health records from four North Carolina congenital heart surgery using indirect identifiers like date of birth, sex, admission, and discharge dates, from 2008 to 2013. Indirect linkage was performed at the admissions level and compared to two other linkages using a "direct identifier," medical record number: (1) linkage between Society of Thoracic Surgeons Congenital Heart Surgery Database and electronic health records from a subset of patients from one North Carolina institution and (2) linkage between Society of Thoracic Surgeons data from two Georgia facilities and Georgia's CHD repository, which also uses direct identifiers for linkage.

RESULTS

Indirect identifiers successfully linked 79% (3692/4685) of Society of Thoracic Surgeons Congenital Heart Surgery Database admissions across four North Carolina hospitals. Direct linkage techniques successfully matched Society of Thoracic Surgeons Congenital Heart Surgery Database to 90.2% of electronic health records from the North Carolina subsample. Linkage between Society of Thoracic Surgeons and Georgia's CHD repository was 99.5% (7,544/7,585).

CONCLUSIONS

Linkage methodology was successfully demonstrated between surgical data and hospital-based electronic health records in North Carolina and Georgia, uniting granular procedural details with clinical, developmental, and economic data. Indirect identifiers linked most patients, consistent with similar linkages in adult populations. Future directions include applying these linkage techniques with other data sources and exploring long-term outcomes in linked populations.

Anticoagulation for post-operative atrial fibrillation after isolated coronary artery bypass grafting: a meta-analysis

BACKGROUND AND AIMS

This study aimed to evaluate clinical outcomes in patients developing post-operative atrial fibrillation (POAF) after coronary artery bypass grafting (CABG) and characterize variations in oral anticoagulation (OAC) use, benefits, and complications.

METHODS

A systematic search identified studies on new-onset POAF after CABG and OAC initiation. Outcomes included risks of thromboembolic events, bleeding, and mortality. Furthermore, a meta-analysis was conducted on these outcomes, stratified by the use or non-use of OAC.

RESULTS

The identified studies were all non-randomized. Among 1 698 307 CABG patients, POAF incidence ranged from 7.9% to 37.6%. Of all POAF patients, 15.5% received OAC. Within 30 days, thromboembolic events occurred at rates of 1.0% (POAF: 0.3%; non-POAF: 0.8%) with 2.0% mortality (POAF: 1.0%; non-POAF: 0.5%). Bleeding rates were 1.1% for POAF patients and 2.7% for non-POAF patients. Over a median of 4.6 years, POAF patients had 1.73 thromboembolic events, 3.39 mortality, and 2.00 bleeding events per 100 person-years; non-POAF patients had 1.14, 2.19, and 1.60, respectively. No significant differences in thromboembolic risks [effect size -0.11 (-0.36 to 0.13)] and mortality [effect size -0.07 (-0.21 to 0.07)] were observed between OAC users and non-users. However, OAC use was associated with higher bleeding risk [effect size 0.32 (0.06-0.58)].

CONCLUSIONS

In multiple timeframes following CABG, the incidence of complications in patients who develop POAF is low. The use of OAC in patients with POAF after CABG is associated with increased bleeding risk.

Surgical Coronary Revascularization in Patients With Underlying Atrial Fibrillation: State-of-the-Art Review

The number of individuals referred for coronary artery bypass grafting (CABG) with preoperative atrial fibrillation (AF) is reported to be 8% to 20%. Atrial fibrillation is a known marker of high-risk patients as it was repeatedly found to negatively influence survival. Therefore, when performing surgical revascularization, consideration should be given to the concomitant treatment of the arrhythmia, the clinical consequences of the arrhythmia itself, and the selection of adequate surgical techniques. This state-of-the-art review aimed to provide a comprehensive analysis of the current understanding of, advancements in, and optimal strategies for CABG in patients with underlying AF. The following topics are considered: stroke prevention, prophylaxis and occurrence of postoperative AF, the role of surgical ablation and left atrial appendage occlusion, and an on-pump vs off-pump strategy. Multiple acute complications can occur in patients with preexisting AF undergoing CABG, each of which can have a significant effect on patient outcomes. Long-term results in these patients and the future perspectives of this scientific area were also addressed. Preoperative arrhythmia should always be considered for surgical ablation because such an approach improves prognosis without increasing perioperative risk. While planning a revascularization strategy, it should be noted that although off-pump coronary artery bypass provides better short-term outcomes, conventional on-pump approach may be beneficial at long-term follow-up. By collecting the current evidence, addressing knowledge gaps, and offering practical recommendations, this state-of-the-art review serves as a valuable resource for clinicians involved in the management of patients with AF undergoing CABG, ultimately contributing to improved outcomes and enhanced patient care.

Half-dose direct oral anticoagulation versus warfarin for atrial fibrillation following cardiac surgery

BACKGROUND

Optimal anticoagulation strategies have not been defined for patients with atrial fibrillation following cardiac surgery.

METHODS

From a total cohort of 228 patients with pre-existing or new onset atrial fibrillation following coronary artery bypass grafting and/or valve surgery, we compared in-hospital and 30-day outcomes in 119 patients treated with low-dose aspirin and a half-dose direct oral anticoagulant (DOAC) versus 109 treated with low-dose aspirin and warfarin.

RESULTS

DOAC patients were older (73.1±7.0 vs. 68.7±11.4 years, P<0.001) and had a lower incidence of preoperative atrial fibrillation (37 [31.1%] vs. 69 [63.3%], P<0.001). Otherwise, the two cohorts were well matched for baseline demographics, cardiovascular risk factors, comorbidities, prior cardiac history and STS Risk Score. In comparison to Warfarin patients, DOAC patients had a shorter length of post-surgical stay (6 [5-8] vs. 7 [5-10] days, P=0.037). The two cohorts, however, had a similar incidence of stroke, transient ischemic attack, reoperation for bleeding and postoperative blood bank product usage. Follow-up 30-day outcomes did not differ between the two groups with respect to mortality (0 [0.0%] vs. 0 [0.0%], P=1.000) and hospital readmission (16 [13.4%] vs. 14 [12.8%], P=0.893), although two DOAC patients required drainage of sanguineous pericardial effusions.

CONCLUSIONS

In comparison to warfarin, half-dose DOAC anticoagulation in patients with atrial fibrillation following cardiac surgery is associated with a shorter postoperative length of stay, without a significant increase in stroke/transient ischemic attack, reoperation for bleeding or postoperative blood product transfusion. Follow-up echocardiography in anticoagulated patients is recommended to rule out significant sanguineous pericardial effusions in the early postoperative period following hospital discharge.

Anticoagulant Prescribing Patterns in New-Onset Atrial Fibrillation After Cardiac Surgery

BACKGROUND

Postoperative atrial fibrillation (POAF) is a common complication after cardiac surgery and is associated with an increased risk of thromboembolic stroke. Recommendations regarding the optimal anticoagulant, timing of initiation, and duration of therapy remain uncertain.

METHODS

Administrative databases were used to include adult patients who presented with POAF after cardiac surgery between January 1, 2015, and December 31, 2020. Key exclusion criteria included preexisting atrial fibrillation, mechanical valve replacement, or anticoagulant prescription fill within 6 months before the index admission.

RESULTS

A total of 3214 of patients were included, and 878 (27.3%) were prescribed an oral anticoagulant (OAC) on discharge, with 536 (61%) prescribed warfarin and 342 (39%) prescribed a direct OAC. More than half of the patients (56.1%) stopped their OAC by 6 months. There was no difference in stroke or systemic embolism at 30 days, 3 months, or 6 months between those with and without anticoagulation prescribed. However, those on any OAC had higher rates of any bleeding at all time points.

CONCLUSIONS

A minority of patients who presented with POAF after cardiac surgery were prescribed OAC, with warfarin being the most common agent. OAC initiation was associated with increased bleeding risk, warranting special consideration when assessing a patient's risk of stroke with the increased risk of bleeding, particularly in the postoperative period.

Recurrence of Atrial Fibrillation in Patients With New-Onset Postoperative Atrial Fibrillation After Coronary Artery Bypass Grafting

Importance

New-onset postoperative atrial fibrillation (POAF) occurs in approximately 30% of patients undergoing coronary artery bypass grafting (CABG). It is unknown whether early recurrence is associated with worse outcomes.

Objective

To test the hypothesis that early AF recurrence in patients with POAF after CABG is associated with worse outcomes.

Design, Setting, and Participants

This Swedish nationwide cohort study used prospectively collected data from the SWEDEHEART (Swedish Web System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies) registry and 3 other mandatory national registries. The study included patients who underwent isolated first-time CABG between January 1, 2007, and December 31, 2020, and developed POAF. Data analysis was performed between March 6 and September 16, 2023.

Exposure

Early AF recurrence defined as an episode of AF leading to hospital care within 3 months after discharge.

Main Outcomes and Measures

The primary outcome was all-cause mortality. Secondary outcomes included ischemic stroke, any thromboembolism, heart failure hospitalization, and major bleeding within 2 years after discharge. The groups were compared with multivariable Cox regression models, with early AF recurrence as a time-dependent covariate. The hypothesis tested was formulated after data collection.

Results

Of the 35 329 patients identified, 10 609 (30.0%) developed POAF after CABG and were included in this study. Their median age was 71 (IQR, 66-76) years. The median follow-up was 7.1 (IQR, 2.9-9.0) years, and most patients (81.6%) were men. Early AF recurrence occurred in 6.7% of patients. Event rates (95% CIs) per 100 patient-years with vs without early AF recurrence were 2.21 (1.49-3.24) vs 2.03 (1.83-2.25) for all-cause mortality, 3.94 (2.92-5.28) vs 2.79 (2.56-3.05) for heart failure hospitalization, and 3.97 (2.95-5.30) vs 2.74 (2.51-2.99) for major bleeding. No association between early AF recurrence and all-cause mortality was observed (adjusted hazard ratio [AHR], 1.17 [95% CI, 0.80-1.74]; P = .41). In exploratory analyses, there was an association with heart failure hospitalization (AHR, 1.80 [95% CI, 1.32-2.45]; P = .001) and major bleeding (AHR, 1.92 [1.42-2.61]; P < .001).

Conclusions and Relevance

In this cohort study of early AF recurrence after POAF in patients who underwent CABG, no association was found between early AF recurrence and all-cause mortality. Exploratory analyses showed associations between AF recurrence and heart failure hospitalization, oral anticoagulation, and major bleeding.

Impact of Oral Anticoagulation on Clinical Outcomes in Postoperative Atrial Fibrillation

INTRODUCTION

The impact of postoperative oral anticoagulation (OAC) with warfarin on postoperative atrial fibrillation (POAF) after coronary artery bypass grafting (CABG) was the focus of this examination of patients from the randomized endo-vein graft prospective (REGROUP) Trial.

MATERIAL AND METHODS

REGROUP was a prospective randomized Veterans Affairs cooperative study comparing endoscopic versus open vein harvest in elective CABG patients (March 2014-April 2017) at 16 Veterans Affairs facilities. This study compared new-onset POAF patients who were treated with warfarin versus no-warfarin. Outcomes included stroke during active follow-up and a major adverse cardiac event composite of mortality, acute myocardial infarction, and repeat revascularization during active and passive follow-up.

RESULTS

Of the 316/1103 (28.6%) of REGROUP patients who developed new-onset POAF, 45 patients were excluded - mainly for preoperative warfarin use. Of the remaining 269 patients, 85 received OAC with warfarin (OAC group); 184 did not (no-OAC group). Stroke rates during active follow-up (32 [IQR 24-38] mo) were 3.5% OAC group versus 5.4% no-OAC group (P = 0.76); major adverse cardiac eventrates were 20% OAC versus 11.4% no-OAC (P = 0.06). On longer follow-up of (median 4.61 [IQR 3.9-5.1] y), discharge OAC use was associated with all-cause mortality after adjusting for Society of Thoracic Surgeons mortality risk (20.0% versus 11.4% no-OAC use; HR = 2.00, 95% CI: 1.05-3.81, P = 0.035).

CONCLUSIONS

REGROUP patients with POAF treated with OAC had similar stroke and higher mortality rates versus no-OAC patients. Further investigation of the risk-benefit ratio of OAC in post-CABG patients and which POAF patient subgroups might derive the most benefit with anticoagulation appears warranted.

The Society of Thoracic Surgeons Adult Cardiac Surgery Database: 2023 Update on Procedure Data and Research

The Society of Thoracic Surgeons (STS) Adult Cardiac Surgery Database is one of the largest and most comprehensive contemporary clinical databases in use. It now contains >9 million procedures from 1010 participants and 3651 active surgeons. Using audited data collection, it has provided the foundation for multiple risk models, performance metrics, health policy decisions, and a trove of research studies to improve the care of patients in need of cardiac surgical procedures. This annual report provides an update on the current status of the database and summarizes the development of new risk models and the STS Online Risk Calculator. Further, it provides insights into current practice patterns, such as the change in the demographics among patients undergoing aortic valve replacement, the use of minimally invasive techniques for valve and bypass surgery, or the adoption of surgical ablation and left atrial appendage ligation among patients with atrial fibrillation. Lastly, an overview of the research conducted using the STS Adult Cardiac Surgery Database and future directions for the database are provided.

Perioperative stroke

Ischaemic or haemorrhagic perioperative stroke (that is, stroke occurring during or within 30 days following surgery) can be a devastating complication following surgery. Incidence is reported in the 0.1-0.7% range in adults undergoing non-cardiac and non-neurological surgery, in the 1-5% range in patients undergoing cardiac surgery and in the 1-10% range following neurological surgery. However, higher rates have been reported when patients are actively assessed and in high-risk populations. Prognosis is significantly worse than stroke occurring in the community, with double the 30-day mortality, greater disability and diminished quality of life among survivors. Considering the annual volume of surgeries performed worldwide, perioperative stroke represents a substantial burden. Despite notable differences in aetiology, patient populations and clinical settings, existing clinical recommendations for perioperative stroke are extrapolated mainly from stroke in the community. Perioperative in-hospital stroke is unique with respect to the stroke occurring in other settings, and it is essential to apply evidence from other settings with caution and to identify existing knowledge gaps in order to effectively guide patient care and future research.

Challenging anticoagulation decisions in atrial fibrillation: a narrative review

Atrial fibrillation (AF) is common and warrants consideration of oral anticoagulant (OAC) medication. Usually, the decision is straightforward, following the pathway outlined in the European Society of Cardiology's guideline; however, certain situations fall outside of this evidence base - such as a diagnosis of subclinical AF made via implanted devices or wearable electrocardiogram monitors, or alternatively diagnosis of 'secondary AF' following a major stressor. Subclinical AF is associated with stroke, though not to the extent of clinical AF, and the benefits of anticoagulation appear to be lower. Longer episodes are more clinically meaningful, and recent randomised controlled trials have demonstrated that some patients derive benefit from OAC. Similarly, when AF is triggered by sepsis or non-cardiac surgery, specific evidence supporting OAC initiation is lacking and clinician behaviour is variable. Observational data demonstrate poorer outcomes in these patients, implying that the perception of a transient, reversible phenomenon may not be correct. Contrastingly, cardiac surgery very frequently induces AF, and the benefits of anticoagulation rarely outweigh the risks of bleeding. Following ischaemic stroke, recent evidence suggests that early (re-)initiation of OAC should be considered as this does not increase the risk of haemorrhagic transformation as previously hypothesised. This narrative review summarises the available literature and outlines, where possible, practical advice for clinicians facing these common clinical dilemmas.

Association Between Intraoperative Landiolol Use and In-Hospital Mortality After Coronary Artery Bypass Grafting: A Nationwide Observational Study in Japan

BACKGROUND

Ischemic heart disease is a leading cause of death worldwide, and coronary artery bypass grafting (CABG) is a major treatment. Landiolol is an ultra-short-acting beta-antagonist known to prevent postoperative atrial fibrillation. However, the effectiveness of intraoperative landiolol on mortality remains unknown. This study aimed to evaluate the association between intraoperative landiolol use and the in-hospital mortality in patients undergoing CABG.

METHODS

To conduct this retrospective cohort study, we used data from the Japanese Diagnosis Procedure Combination inpatient database. All patients who underwent CABG during hospitalization between July 1, 2010, and March 31, 2020, were included. Patients who received intraoperative landiolol were defined as the landiolol group, whereas the other patients were defined as the control group. The primary outcome was in-hospital mortality. Propensity score matching was used to compare the landiolol and control groups.

RESULTS

In total, 118,506 patients were eligible for this study, including 25,219 (21%) in the landiolol group and 93,287 (79%) in the control group. One-to-one propensity score matching created 24,893 pairs. After propensity score matching, the in-hospital mortality was significantly lower in the landiolol group than that in the control group (3.7% vs 4.3%; odds ratio 0.85; 95% confidence interval 0.78 to 0.94; P = .010).

CONCLUSIONS

Intraoperative landiolol use was associated with decreased in-hospital mortality in patients undergoing CABG. Further randomized controlled trials are required to confirm these findings.

Postoperative Atrial Fibrillation After Surgical Aortic Valve Replacement: Amiodarone and Warfarin Use

INTRODUCTION

The association between amiodarone treatment for postoperative atrial fibrillation (POAF) after surgical aortic valve replacement (SAVR) and both the return to normal sinus rhythm (NSR) and anticoagulation use at discharge has not been extensively studied.

METHODS

We retrospectively identified all patients who underwent biological SAVR with or without concomitant coronary artery bypass grafting (CABG) at a Veterans Affairs Medical Center (2005-2015). We reviewed new-onset POAF, amiodarone use, return to NSR, and anticoagulation use with warfarin. Discharge rhythm and warfarin administration were compared among patients with POAF who were treated with amiodarone and patients who did not receive amiodarone.

RESULTS

Of the 395 patients (186 AVR/coronary artery bypass grafting; 209 AVR) studied, POAF developed in 191 patients (48.0%); 80.1% (153/191) of these patients received amiodarone. Among patients treated with amiodarone, 70.6% (108/153) were in SR at the time of discharge versus 65.8% (25/38) of POAF patients who were not treated with amiodarone (P = 0.57). Among amiodarone-treated patients, 30.7% (47/153) were discharged with warfarin; among patients not treated with amiodarone, 31.6% (12/38) were discharged with warfarin (P = 0.92). Among amiodarone-treated patients discharged in NSR, 89.9% (97/108 patients) were not discharged with warfarin; among patients not treated with amiodarone who were discharged in NSR, 92% (23/25) were not discharged with warfarin (P = 0.74).

CONCLUSIONS

POAF after SAVR appears common. Although amiodarone is often used for POAF patients, its use does not appear to be associated with surgeons' decision to anticoagulate patients. Surgeons' preferences for using rhythm control and antithrombotic therapy for POAF after SAVR warrant further exploration.

The Management of Postoperative Atrial Fibrillation (POAF): A Systematic Review

Postoperative atrial fibrillation (POAF) refers to new-onset atrial fibrillation (AF) that develops after surgery and is associated with an increased risk of mortality and thromboembolic events. The optimal management and treatment methods for POAF complications are not yet fully established. This systematic review aimed to evaluate the various treatment and management approaches currently available in terms of their suitability, efficacy, and side effects in handling POAF incidence post-surgery. Google Scholar and PubMed electronic databases were searched extensively for relevant articles examining the various management techniques currently used to manage POAF and published between 2018 and 2023. Data were collected on the type of surgery the patients underwent, POAF definition period, intervention, and outcome of interest. Following a systematic assessment guided by the inclusion criteria, 10 of the 579 studies retrieved were included in this study, and 293,417 POAF cases were recorded. Three of these studies used different rhythm control and rate control treatments to manage POAF cases, while seven studies used various anticoagulation therapies to manage POAF incidence. For asymptomatic patients within one to three days of surgery, rate control is sufficient to manage POAF, and routine rhythm control is not needed; rhythm control should be reserved for patients who develop complications such as hemodynamic instability. Anticoagulation was performed in patients whose POAF exceeded four days after surgery. Anticoagulation was associated with an increased risk of mortality, stroke, thromboembolic events, and major bleeding in patients who underwent coronary artery bypass graft (CABG) surgery. In contrast, in a few other studies, anticoagulation treatment led to improved outcomes in patients who developed POAF. A wide range of management methods are available for POAF after different types of surgery. However, there is only limited evidence to guide the clinical practice. The data available are mainly retrospective and insufficient to accurately evaluate the efficacy of the various management methods available for POAF. Future research should make efforts to standardize the treatment for this condition.