Surgical Ablation of Atrial Fibrillation in the United States: Trends and Propensity Matched Outcomes

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society (HRS), the Asia Pacific HRS, and the Latin American HRS.

The Society of Thoracic Surgeons 2023 Clinical Practice Guidelines for the Surgical Treatment of Atrial Fibrillation

The Society of Thoracic Surgeons 2023 Clinical Practice Guidelines for the Surgical Treatment of Atrial Fibrillation incorporate the most recent evidence for surgical ablation and left atrial appendage occlusion in different clinical scenarios. Substantial new evidence regarding the risks and benefits of surgical left atrial appendage occlusion and the long-term benefits of surgical ablation has been produced in the last 5 years. Compared with the 2017 clinical practice guideline, the current update has an emphasis on surgical ablation in first-time, nonemergent cardiac surgery and its long-term benefits, an extension of the recommendation to perform surgical ablation in all patients with atrial fibrillation undergoing first-time, nonemergent cardiac surgery, and a new class I recommendation for left atrial appendage occlusion in all patients with atrial fibrillation undergoing first-time, nonemergent cardiac surgery. Further guidance is provided for patients with structural heart disease and atrial fibrillation being considered for transcatheter valve repair or replacement, as well as patients in need of isolated left atrial appendage management who are not candidates for surgical ablation. The importance of a multidisciplinary team assessment, treatment planning, and long-term follow-up are reiterated in this clinical practice guideline with a class I recommendation, along with the other recommendations from the 2017 guidelines that remained unchanged in their class of recommendation and level of evidence.

Epicardial and endocardial surgical ablation of atrial fibrillation: outcomes from CASE-AF Registry

OBJECTIVES

The German CArdioSurgEry Atrial Fibrillation Registry is a prospective, multicentric registry analysing outcomes of patients undergoing surgical ablation for atrial fibrillation as concomitant or stand-alone procedures. This data sub-analysis of the German CArdioSurgEry Atrial Fibrillation Registry aims to describe the in-hospital and 1-year outcomes after concomitant surgical ablation, based on 2 different ablation approaches, epicardial and endocardial surgical ablation.

METHODS

Between January 2017 and April 2020, 17 German cardiosurgical units enrolled 763 consecutive patients after concomitant surgical ablation. In the epicardial group, 413 patients (54.1%), 95.6% underwent radiofrequency ablation. In the endocardial group, 350 patients (45.9%), 97.7% underwent cryoablation. 61.5% of patients in the epicardial group and 49.4% of patients in the endocardial group presenting with paroxysmal atrial fibrillation. Pre-, intra- and post-operative data were gathered.

RESULTS

Upon discharge, 32.3% (n = 109) of patients after epicardial surgical ablation and 24.0% (n = 72) of patients after endocardial surgical ablation showed recurrence of atrial fibrillation. The in-hospital mortality rate was low, 2.2% (n = 9) in the epicardial and 2.9% (n = 10) in the endocardial group. The overall 1-year procedural success rate was 58.4% in the epicardial and 62.2% in the endocardial group, with significant symptom improvement in both groups. The 1-year mortality rate was 7.7% (n = 30) in epicardial and 5.0% (n = 17) in the endocardial group.

CONCLUSIONS

Concomitant surgical ablation is safe and effective with significant improvement in patient symptoms and freedom from atrial fibrillation. Adequate cardiac rhythm monitoring should be prioritized for higher quality data acquisition.

Concomitant Surgical Ablation in Paroxysmal vs Persistent Atrial Fibrillation During Mitral Surgery

BACKGROUND

Despite prospective randomized evidence supporting concomitant treatment of atrial fibrillation (AF) during mitral valve (MV) surgery, variation in surgical management of AF remains. We assessed longitudinal outcomes after surgical treatment of persistent or paroxysmal AF during MV surgery in Medicare beneficiaries.

METHODS

All Medicare beneficiaries with a diagnosis of AF undergoing MV surgery (2018-2020) were evaluated. Patients were stratified by no AF treatment, left atrial appendage obliteration (LAAO) alone, or surgical ablation and LAAO (SA+LAAO). Doubly robust risk adjustment and subgroup analysis by persistent or paroxysmal AF were performed.

RESULTS

A total of 7517 patients with preoperative AF underwent MV surgery (32.1% no AF treatment, 23.1% LAAO alone, 44.7% SA+LAAO). After doubly robust risk adjustment, AF treatment with SA+LAAO or LAAO alone were associated with lower 3-year readmission for stroke or bleeding. However, SA+LAAO was associated with reduced 3-year mortality and readmission for AF or heart failure compared with no AF treatment or LAAO alone. Compared with no AF treatment or LAAO alone, SA+LAAO was associated with lower composite end point of stroke (hazard ratio, 0.75) or death (hazard ratio, 0.83) at 3 years. Subgroup analysis identified similar longitudinal benefits of SA+LAAO in patients with persistent or paroxysmal AF.

CONCLUSIONS

In Medicare beneficiaries with AF undergoing MV surgery, SA+LAAO was associated with improved longitudinal outcomes compared with LAAO alone or no AF treatment in patients with paroxysmal or persistent AF. These contemporary real-world data further clarify the benefit of SA+LAAO during MV surgery across all types of AF.

Surgical ablation of atrial fibrillation is associated with improved survival compared with appendage obliteration alone: An analysis of 100,000 Medicare beneficiaries

OBJECTIVE

Societal guidelines support the concomitant surgical ablation of atrial fibrillation in patients undergoing cardiac surgery. Recent evidence has highlighted the stroke reduction of left atrial appendage obliteration with or without surgical ablation in similar populations. To inform clinical decision-making, we evaluated real-world outcomes of patients with atrial fibrillation undergoing cardiac surgery by comparing no atrial fibrillation management with left atrial appendage obliteration alone versus surgical ablation + left atrial appendage obliteration.

METHODS

By using the US Centers for Medicare and Medicaid Services inpatient claims database, we evaluated all beneficiaries aged 65 years and older with a diagnosis of atrial fibrillation undergoing coronary artery bypass grafting or mitral/aortic/tricuspid valve repair or replacement between January 2018 and December 2020. Diagnosis-related group and International Classification of Diseases, 10th Revision procedure codes were used to define variables. Risk adjustment was performed with regression analysis using inverse probability weighting of propensity scores and Cox proportional hazards models. Subgroup analyses stratified patients by primary operation and paroxysmal or persistent atrial fibrillation.

RESULTS

A total of 103,382 patients with preoperative atrial fibrillation were stratified by surgical ablation + left atrial appendage obliteration (10,437; 10.1%), left atrial appendage obliteration alone (12,901; 12.5%), or no atrial fibrillation management (80,044; 77.4%). Patients with persistent atrial fibrillation (21,076; 20.4%) received the highest proportion of surgical ablation + left atrial appendage obliteration (4661 19.4%) and left atrial appendage obliteration alone (3%724%; 15.4%) versus no atrial fibrillation management (15,688; 65.2%). Likewise, patients undergoing open atrial operations (mitral/tricuspid; 17,204; 16.6%) had higher proportions of atrial fibrillation treatment (surgical ablation + left atrial appendage obliteration 5267 30.6%; left atrial appendage obliteration alone 4259 24.8%; no atrial fibrillation management 7678 44.6%). After robust risk adjustment, surgical ablation + left atrial appendage obliteration was independently associated with reduced 3-year mortality compared with no atrial fibrillation treatment (hazard ratio, 0.68, P < .001) and left atrial appendage obliteration alone (hazard ratio, 0.90, P < .001). Compared with no atrial fibrillation treatment, readmissions for embolic stroke were lower with both surgical ablation + left atrial appendage obliteration (hazard ratio, 0.77, P = .009) and left atrial appendage obliteration alone (hazard ratio, 0.73, P < .001). Reduction in 3-year composite mortality or stroke after surgical ablation + left atrial appendage obliteration was superior to left atrial appendage alone (hazard ratio, 0.90, P = .035).

CONCLUSIONS

In Medicare beneficiaries with atrial fibrillation undergoing cardiac surgery, the surgical management of atrial fibrillation was associated with lower 3-year mortality and readmission for stroke, with surgical ablation + left atrial appendage obliteration being associated with higher survival compared with left atrial appendage obliteration alone.

Lesion durability found during mandated percutaneous catheter ablation after surgical cryo-ablation for treatment of non-paroxysmal atrial fibrillation

OBJECTIVES

Current recommendations support surgical treatment of atrial fibrillation (AF) in patients indicated for cardiac surgery. These procedures are referred to as concomitant and may be carried out using radiofrequency energy or cryo-ablation. This study aimed to assess the electrophysiological findings in patients undergoing concomitant cryo-ablation.

METHODS

Patients with non-paroxysmal AF undergoing coronary artery bypass grafting and/or valve repair/replacement were included in the trial if concomitant cryo-ablation was part of the treatment plan according to current guidelines. The patients reported in this study were assigned to undergo staged percutaneous radiofrequency catheter ablation (PRFCA), i.e., hybrid treatment, as a part of the SURHYB trial protocol.

RESULTS

We analyzed 103 patients who underwent PRFCA 105 ± 35 days after surgery. Left and right pulmonary veins (PVs) were found isolated in 65 (63.1%) and 63 (61.2%) patients, respectively. The LA posterior wall isolation and mitral isthmus conduction block were found in 38 (36.9%) and 18 (20.0%) patients, respectively. Electrical reconnections (gaps) in the left PVs were more often localized superiorly than inferiorly (57.9% vs. 26.3%, P = 0.005) and anteriorly than posteriorly (65.8% vs. 31.6%, P = 0.003). Gaps in the right PVs were more equally distributed anteroposteriorly but dominated in superior segments (72.5% vs. 40.0%, P = 0.003). There was a higher number of gaps on the roof line compared to the inferior line (131 (67.2%) vs. 67 (42.2%), P < 0.001). Compared to epicardial cryo-ablation, endocardial was more effective in creating PVs and LA posterior wall isolation (P < 0.05). Cryo-ablation using nitrous oxide (N20) or argon (Ar) gas as cooling agents was similarly effective (P = NS).

CONCLUSIONS

The effectiveness of surgical cryo-ablation in achieving transmural and durable lesions in the left atrium is surprisingly low. Gaps are located predominantly in the superior and anterior portions of the PVs and on the roof line. Endocardial cryo-ablation is more effective than epicardial ablation, irrespective of the cooling agent used.

Surgical Ablation of Atrial Fibrillation in High-Risk Patients: Success versus Risk

BACKGROUND

 Surgical atrial ablation is evaluated by surgeons in relation to the estimated surgical risk. We analyze whether high-risk patients (HRPs) experience risk escalation by ablation procedures.

METHODS

 The CASE-Atrial Fibrillation (AF) registry is a prospective, multicenter, all-comers registry of atrial ablation in cardiac surgery. We analyzed the 1-year outcome regarding survival and rhythm endpoints of 1,000 consecutive patients according to the operative risk classification (EuroSCORE II ≤ 2 vs. >2).

RESULTS

 Higher NYHA (New York Heart Association) score, ischemic heart failure, status poststroke, renal insufficiency, chronic obstructive pulmonary disease, and diabetes mellitus were strongly represented in HRPs. HRPs exhibit more left ventricular ejection fraction < 40% (19.2 vs. 8.8%; p < 0.001) but identical left atrial diameter and left ventricular end-diastolic diameter compared with low-risk patients (LRPs). CHA2DS-Vasc-score (2.4 ± 1 vs. 3.6 ± 1.5; p < 0.001), sternotomies, combination surgeries, coronary artery bypass graft, and mitral valve procedures were increased in HRPs. LRPs underwent stand-alone ablations as well. Ablation energy did not differ. Left atrial appendage closure was performed in up to 86.1% (mainly cut-and-sew procedures). Mortality corresponded to the original risk class without an escalation that may be related to ablation, stroke rate, or myocardial infarction. A total of 60.6% of HRPs versus 75.1% of LRPs were discharged in sinus rhythm. Long-term EHRA (European Heart Rhythm Association) score symptoms were lower in HRPs. Repeated rhythm therapies were rare. Additional antiarrhythmics received a minority without group dependency. A total of 1.6 versus 4.1% of HRPs (p = 0.042) underwent long-term stroke; excess mortality was not observed. Anticoagulation remained common in HRPs.

CONCLUSION

 Surgical risk and long-term mortality are determined by the underlying disease. In HRPs, freedom from AF and symptom relief can be achieved. Preoperative risk scores should not lead to withholding an ablation procedure.

Efficacy of a surgical cardiac ablation clamp using nanosecond pulsed electric fields: An acute porcine model

OBJECTIVE

To examine the effectiveness of a recently developed nonthermal technology, nanosecond pulse-field ablation (nsPFA), for surgical ablation of the atria in a beating heart porcine model.

METHODS

Six pigs underwent sternotomy and ablation using an nsPFA parallel clamp. The ablation electrodes (53 mm long) were embedded in the jaws of the clamp. Nine lesions per pig were created in locations chosen to be representative of the Cox-maze procedure. Four lesions were intended to electrically isolate parts of the atrium: the right atrial appendage, left atrial appendage, right pulmonary veins, and left pulmonary veins. For these lesions, exit block testing was performed both after ablation and before euthanasia; the time between the 2 tests was 3.3 ± 0.5 hours (range, 2-4 hours). Using purse string sutures, 5 more lesions were created up to the superior vena cava, down to the inferior vena cava, across the right atrial free wall, and at 2 distinct locations on the left atrial free wall. The clamp delivered a train of nanosecond duration pulses, with a total duration of 2.5 seconds, independent of tissue thickness. The heart tissue was stained with 1% triphenyltetrazolium chloride after a dwelling period of 2 hours. Subsequently, each lesion was cross sectioned at 5-mm intervals to assess the ablation depth and transmurality. In some sections, transmurality could not be established on the basis of triphenyltetrazolium chloride staining alone; for these lesions, Gomori-trichrome stains were used, and the histologic sections were evaluated for transmurality.

RESULTS

The ablation time was 2.5 seconds per lesion, for a total of only 22.5 seconds ablation time to create 9 lesions. A total of 53 lesions were created, resulting in 388 separate histologic sections. Transmurality was established in 386 sections (99.5%). Mean tissue thickness was 3.1 ± 1.5 mm (range, 0.2-8.6 mm). Exit block was confirmed in 23 of the 24 lesions (96%) postablation and 23 of 24 (96%) before the animals were humanely killed. Over the course of the procedure, neither pulse-induced arrhythmias nor any other complications were noted.

CONCLUSIONS

The novel nsPFA clamp device was effective in creating acute conduction block and transmural lesions in both the right and left atria in an acute porcine model. This nonthermal energy source has great potential to both shorten procedural time and enable effective ablation in the beating heart.

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.

Randomized feasibility trial of prophylactic radiofrequency ablation to prevent atrial fibrillation after cardiac surgery

OBJECTIVE

To evaluate the feasibility of prophylactic radiofrequency isolation of the pulmonary veins, with left atrial appendage amputation, to reduce the incidence of postoperative atrial fibrillation after cardiac surgery in patients aged 70 years and older.

METHODS

The Federal Food and Drug Administration granted an investigational device exemption to utilize a bipolar radiofrequency clamp for prophylactic pulmonary vein isolation in a limited feasibility trial. Sixty-two patients without prior dysrhythmias were prospectively randomized to undergo either their index cardiac surgical procedure or bilateral pulmonary vein isolation and left atrial appendage amputation during their cardiac operation. The primary outcome was occurrence of in-hospital postoperative atrial fibrillation. Subjects were on 24-hour telemetry until discharge. Dysrhythmias, any episode of atrial fibrillation >30 seconds, were confirmed by electrophysiologists blinded to the study.

RESULTS

Sixty patients, mean age 75 years and mean Congestive heart failure, Hypertension, Age (>65 = 1, >75 = 2 points), Diabetes, previous Stroke/Transient ischemic attack (2 points), Vascular disease, Gender (female) score of 4, were analyzed. Thirty-one patients randomized to control and 29 to the treatment group. The majority of patients in each group underwent isolated coronary artery bypass grafting. No perioperative complications related to the treatment procedure, need for permanent pacemaker, or mortality occurred. The in-hospital incidence of postoperative atrial fibrillation was 55% (17 out of 31) in the control group and 7% (2 out of 29) in the treatment group (P < .001) The control group had a significantly higher requirement for antiarrhythmic medications at discharge: 45% (14 out of 31) versus 7% (2 out of 29) in the treatment group (P < .001).

CONCLUSIONS

Prophylactic radiofrequency isolation of the pulmonary veins with left atrial appendage amputation during the primary cardiac surgical operation reduced the incidence of postoperative atrial fibrillation in patients aged 70 years and older with no history of atrial arrhythmias.

Concomitant Treatment of Atrial Fibrillation in Isolated Coronary Artery Bypass Grafting

BACKGROUND

Societal guidelines support concomitant management of atrial fibrillation (AF) in patients undergoing cardiac surgery. To assess real-world adoption and outcomes, this study evaluated Medicare beneficiaries with AF who underwent isolated coronary artery bypass grafting (CABG) with surgical ablation (SA) or left atrial appendage obliteration (LAAO) or both procedures in combination (SA + LAAO).

METHODS

The US Centers for Medicare & Medicaid Services inpatient claims database identified all patients with AF who underwent isolated CABG from 2018 to 2020. Diagnosis-related group and International Classification of Diseases-10th revision procedure codes defined covariates for doubly robust risk adjustment.

RESULTS

A total of 19,524 patients with preoperative AF who underwent isolated CABG were stratified by SA + LAAO (3475 patients; 17.8%), LAAO only (4541 patients; 23.3%), or no AF treatment (11,508 patients; 58.9%). After doubly robust risk adjustment, longitudinal analysis highlighted that concomitant AF treatment with SA + LAAO (hazard ratio [HR], 0.74; P = .049) or LAAO alone (HR, 0.75; P = . 031) was associated with a significant reduction in readmission for stroke at 3 years compared with no AF treatment. Furthermore, SA + LAAO (HR, 0.86; P = .016) but not LAAO alone (HR, 0.97; P = .573) was associated with improved survival compared with no AF treatment. Finally, SA + LAAO was associated with a superior composite outcome of freedom from stroke or death at 3 years compared with LAAO alone (HR, 0.86;, P = .033) or no AF treatment (HR, 0.81; P = .001).

CONCLUSIONS

In Medicare beneficiaries with AF who underwent isolated CABG, concomitant AF treatment was associated with reduced 3-year readmission for stroke. SA + LAAO was associated with superior reduction in stroke or death at 3 years compared with LAAO alone or no AF treatment.

Statewide data on surgical ablation for atrial fibrillation: The data provide a path forward

OBJECTIVE

Atrial fibrillation (AF), if left untreated, is associated with increased intermediate and long-term morbidity/mortality. Surgical treatment for AF is lacking standardization in patient selection and lesion set, despite clear support from multi-society guidelines. The aim of this study was to analyze a statewide cardiac surgery registry to establish whether or not there is an association between center volume and type of index procedure with performance of surgical ablation (SA) for AF, the lesion set chosen, and ablation technology used.

METHODS

Adult, first-time, nonemergency patients with preoperative AF between 2014 and 2022 excluding standalone SA procedures from a statewide registry of Society of Thoracic Surgeons data were included (N = 4320). AF treatment variability by hospital volume (ordered from smallest to largest) and surgery type were examined with χ2 analyses. Hospital-level Spearman correlations compared hospital volume with proportion of AF patients treated with SA.

RESULTS

Overall, 37% of patients with AF were ablated at the time of surgery (63% of mitral procedures, 26% of non-mitrals) and 15% had left atrial appendage management only. There was a significant temporal trend of increasing performance of SA for AF over time (Cochran-Armitage = 27.8; P < .001). Hospital cardiac surgery volume did not correlate with the proportion of AF patients treated with SA (rs = 0.19; P = .603) with a rate of SA below the state average for academic centers. Of cases with SA (n = 1582), only 43% had a biatrial lesion set. Procedures that involved mitral surgery were more likely to include a biatrial lesion set (χ2 = 392.3; P < .001) for both paroxysmal and persistent AF. Similarly, ablation technology use was variable by type of concomitant operation (χ2 = 219.0; P < .001) such that radiofrequency energy was more likely to be used in non-mitral procedures.

CONCLUSIONS

These results indicate an increase in adoption of SA for AF over time. No association between greater hospital volume or academic status and performance of SA for AF was established. Similar to national data, the type of index procedure remains the most consistent factor in the decision to perform SA with a disconnect between AF pathophysiology and decision making on the type of SA performed. This analysis demonstrates a gap between evidence-based guidelines and real-world practice, highlighting an opportunity to confer the benefits of concomitant SA to more patients.

Evaluation of sex differences in the receipt of concomitant atrial fibrillation procedures during nonmitral cardiac surgery

OBJECTIVE

Women are less likely to receive guideline-recommended cardiovascular care, but evaluation of sex-based disparities in cardiac surgical procedures is limited. Receipt of concomitant atrial fibrillation (AF) procedures during nonmitral cardiac surgery was compared by sex for patients with preoperative AF.

METHODS

Patients with preoperative AF undergoing coronary artery bypass grafting and/or aortic valve replacement at any of the 33 hospitals in Michigan from 2014 to 2022 were included. Patients with prior cardiac surgery, transcatheter AF procedure, or emergency/salvage status were excluded. Hierarchical logistic regression identified predictors of concomitant AF procedures, account for hospital and surgeon as random effects.

RESULTS

Of 5460 patients with preoperative AF undergoing nonmitral cardiac surgery, 24% (n = 1291) were women with a mean age of 71 years. Women were more likely to have paroxysmal (vs persistent) AF than men (80% vs 72%; P < .001) and had a higher mean predicted risk of mortality (5% vs 3%; P < .001). The unadjusted rate of concomitant AF procedure was 59% for women and 67% for men (P < .001). After risk adjustment, women had 26% lower adjusted odds of concomitant AF procedure than men (adjusted odds ratio, 0.74; 95% CI, 0.64-0.86; P < .001). Female sex was the risk factor associated with the lowest odds of concomitant AF procedure.

CONCLUSIONS

Women are less likely to receive guideline recommended concomitant AF procedure during nonmitral surgery. Identification of barriers to concomitant AF procedure in women may improve treatment of AF.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society, the Asia Pacific Heart Rhythm Society, and the Latin American Heart Rhythm Society.

Additional bypass graft or concomitant surgical ablation? Insights from the HEIST registry

BACKGROUND

Surgical ablation for atrial fibrillation at the time of isolated coronary artery bypass grafting is reluctantly attempted. Meanwhile, complete revascularization is not always possible in these patients. We attempted to counterbalance the long-term benefits of surgical ablation against the risks of incomplete revascularization.

METHODS

Atrial fibrillation patients undergoing isolated coronary artery bypass grafting for multivessel disease between 2012 to 2022 and included in the HEart surgery In atrial fibrillation and Supraventricular Tachycardia registry were divided into complete revascularization, complete revascularization with additional grafts, and incomplete revascularization cohorts; these were further split into surgical ablation and non-surgical ablation subgroups.

RESULTS

A total of 8,405 patients (78% men; age 69.3 ± 7.9) were included; of those, 5,918 (70.4%) had complete revascularization, and 556 (6.6%) had surgical ablation performed. Number of anastomoses was 2.7 ± 1.2. The median follow-up was 5.1 [interquartile range 2.1-8.8] years. In patients in whom complete revascularization was achieved, surgical ablation was associated with long-term survival benefit: hazard ratio 0.69; 95% confidence intervals (0.50-0.94); P = .020 compared with grafting additional lesions. Similarly, in patients in whom complete revascularization was not achieved, surgical ablation was associated with a long-term survival benefit of 0.68 (0.49-0.94); P = .019. When comparing surgical ablation on top of incomplete revascularization against complete revascularization without additional grafts or surgical ablation, there was no difference between the 2: 0.84 (0.61-1.17); P = .307, which was also consistent in the propensity score-matched analysis: 0.75 (0.39-1.43); P = .379.

CONCLUSION

To achieve complete revascularization is of utmost importance. However, when facing incomplete revascularization at the time of coronary artery bypass grafting in a patient with underlying atrial fibrillation, concomitant surgical ablation on top of incomplete revascularization is associated with similar long-term survival as complete revascularization without surgical ablation.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society, the Asia Pacific Heart Rhythm Society, and the Latin American Heart Rhythm Society .

Left atrial strain predicts the rhythm outcome in patients with persistent atrial fibrillation undergoing left atrial cryoablation during minimally invasive mitral valve repair

Objectives

Patients with atrial fibrillation (AF) have lower left atrial (LA) strain, which is a predictor for LA function. Here, we evaluated the prognostic value of LA strain to predict the rhythm outcome in patients with persistent AF undergoing LA cryoablation concomitant to minimally invasive mitral valve repair.

Methods

Between 01/2016 and 12/2020, 72 patients with persistent AF underwent LA cryoablation during minimally invasive mitral valve surgery. All patients received a complete LA lesion set and left atrial appendage (LAA) closure with a clip. All patients received preoperative transthoracic echocardiography (TTE) with LA and left ventricular strain measurements. Preoperative LA and LV strain analysis was correlated with postoperative rhythm outcome.

Results

The mean age of the patients was 66.9 ± 7.2 years, of whom 42 (58%) were male patients. No major ablation-related complications occurred in any of the patients. Successful LAA closure was confirmed by intraoperative echocardiography in all patients. The 1-year survival rate was 97%. Freedom from AF at 12 months was 72% and 68% off antiarrhythmic drugs. Preoperative LA strain values were statistically significantly higher in patients with freedom from AF at 12 months of follow-up (12.7% ± 6.9% vs. 4.9% ± 4.1%, p = 0.006). Preoperative LV strain value was not associated with postoperative rhythm outcome. In multivariate logistic regression analysis, LA strain (p < 0.001) and AF duration (p = 0.017) were predictors for freedom from AF at 12 months of follow-up.

Conclusions

In our study, LA strain analysis predicted the rhythm outcome in patients with persistent AF undergoing concomitant surgical AF ablation. In the future, LA strain might be a useful tool to guide decision-making on ablation strategies in patients with persistent AF.

Safety and efficacy of Cox-Maze procedure for atrial fibrillation during mitral valve surgery: a meta-analysis of randomized controlled trials

BACKGROUND

Cox-Maze procedure is currently the gold standard treatment for atrial fibrillation (AF). However, data on the effectiveness of the Cox-Maze procedure after concomitant mitral valve surgery (MVS) are not well established. The aim of this study was to assess the safety and efficacy of Cox-Maze procedure versus no-maze procedure n in AF patients undergoing mitral valve surgery through a systematic review of the literature and meta-analysis.

METHODS

A systematic search on PubMed/MEDLINE, EMBASE, and Cochrane Central Register of Clinical Trials (Cochrane Library, Issue 02, 2017) databases were performed using three databases from their inception to March 2023, identifying all relevant randomized controlled trials (RCTs) comparing Cox-Maze procedure versus no procedure in AF patients undergoing mitral valve surgery. Data were extracted and analyzed according to predefined clinical endpoints.

RESULTS

Nine RCTs meeting the inclusion criteria were included in this systematic review with 663 patients in total (341 concomitant Cox-Maze with MVS and 322 MVS alone). Across all studies with included AF patients undergoing MV surgery, the concomitant Cox-Maze procedure was associated with significantly higher sinus rhythm rate at discharge, 6 months, and 12 months follow-up when compared with the no-Maze group. Results indicated that there was no significant difference between the Cox-Maze and no-Maze groups in terms of 1 year all-cause mortality, pacemaker implantation, stroke, and thromboembolism.

CONCLUSIONS

Our systematic review suggested that RCTs have demonstrated the addition of the Cox-Maze procedure for AF leads to a significantly higher rate of sinus rhythm in mitral valve surgical patients, with no increase in the rates of mortality, pacemaker implantation, stroke, and thromboembolism.

Left atrial appendage occlusion for patients with valvular diseases without atrial fibrillation (the OPINION Study): study protocol for a multicentre, randomised controlled trial

INTRODUCTION

Atrial fibrillation (AF) is a significant cause of perioperative stroke in aortic and mitral valve surgeries. Although several large studies have evaluated surgical left atrial appendage occlusion (SLAAO) during cardiac surgeries, their retrospective nature and an uncontrolled broad spectrum of conditions leave them subject to potential residual confounding. This trial aims to test the hypothesis that opportunistic SLAAO can prevent long-term stroke after cardiac surgery in patients receiving mitral or aortic valve surgeries without a history of AF and with a CHA2DS2-VASc score of 2 or higher.

METHODS AND DESIGN

This study is a single-blinded, multicentre, randomised controlled trial. A total of 2118 patients planning to undergo aortic or mitral surgery without AF will be recruited and equally randomised into intervention or control arms at a 1:1 ratio. In the intervention arm, suture excision of the left atrial appendage (LAA) will be performed during the operation in addition to the original surgery plan. In the control arm, the operation will be performed according to the surgery plan without any intervention on the LAA. The primary outcome is a composite of newly occurred ischaemic stroke or transient ischaemic attack and cardiovascular mortality during a 1-year follow-up. Secondary outcomes include postoperative AF, cardiovascular mortality, newly occurred ischaemic stroke, newly occurred transient ischaemic attack, newly occurred haemorrhagic stroke, bleeding events, and AF-associated health utilisation.

ETHICS AND DISSEMINATION

The Ethics Committee in Fuwai Hospital approved this study. Patients will give informed consent to the study. An information leaflet will be provided to participating patients to introduce the SLAAO procedure. Patients and the public will not get involved in developing the research hypothesis, study design or any other part of this protocol. We plan to publish several papers in peer-reviewed journals about the current research and these will include a description of the study's development and the main findings of the study.

TRIAL REGISTRATION NUMBER

ChiCTR2100042238.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Patients With Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

Atrial fibrillation ablation improves late survival after concomitant cardiac surgery

OBJECTIVE

Preoperative atrial fibrillation (AF) increases risk of stroke, heart failure, and all-cause mortality after cardiac surgery. Despite encouraging results and guideline recommendations, surgical ablation (SA) for AF concomitant with other heart surgery remains low. In the current study we aimed to address the long-term mortality after SA concomitant with cardiac surgery.

METHODS

This report pertains to the HEart surgery In atrial fibrillation and Supraventricular Tachycardia (HEIST) registry. We identified 20,765 adult patients (62% male) with preoperative AF who underwent conventional sternotomy heart surgery between 2010 and 2021 in 8 tertiary centers in Poland, Netherlands, and Italy. We used Cox proportional hazards models for computations and propensity score matching to minimize differences in baseline characteristics.

RESULTS

Of included patients, 2755 (13.4%) underwent SA for AF. The highest rates of SA were observed for mitral interventions (mitral valve repair or replacement and tricuspid intervention, 25.2%), lowest for isolated coronary artery bypass grafting (6.2%). Patients in the SA group were younger (mean age 64.5 ± 9.0 years vs 68.7 ± 16.0 years; P < .001) and lower risk (mean European System for Cardiac Operative Risk Evaluation [EuroSCORE] II, 4.1 vs 5.7; P < .001). During the 11-year study period, there was a mortality reduction associated with SA (hazard ratio, 0.57; 95% CI, 0.52-0.62; P < .001). After propensity matching, 2750 pairs with similar baseline characteristics were identified. SA was associated with 16% mortality decline (hazard ratio, 0.84; 95% CI, 0.75-0.94; P = .003).

CONCLUSIONS

In this multicenter, retrospective, propensity matched study, SA concomitant with other cardiac surgery was associated with improved long-term survival regardless of baseline surgical risk.

Influence of concomitant ablation of nonparoxysmal atrial fibrillation during coronary artery bypass grafting on mortality and readmissions

Objective

We determined the utilization rate of surgical ablation (SA) during coronary artery bypass grafting (CABG) and compared outcomes between CABG with or without SA in a national cohort.

Methods

The January 2016 to December 2018 Nationwide Readmissions Database was searched for all patients undergoing isolated CABG with preoperative persistent or chronic atrial fibrillation by using the International Classification of Diseases, 10th Revision classification. Propensity score matching and multivariate logistic regressions were performed to compare outcomes, and Cox proportional hazards model was used to assess risk factors for 1-year readmission.

Results

Of 18,899 patients undergoing CABG with nonparoxysmal atrial fibrillation, 78% (n = 14,776) underwent CABG alone and 22% (n = 4123) underwent CABG with SA. In the propensity score-matched cohort (n = 8116), CABG with SA (n = 4054) (vs CABG alone [n = 4112]) was not associated with increased in-hospital mortality (3.4% [139 out of 4112] vs 3.9% [159 ut of 4054]; P = .4), index-hospitalization length of stay (10 days vs 10 days; P = .3), 30-day readmission (19.1% [693 out of 3362] vs 17.2% [609 out of 3537]; P = .2), or 90-day readmission (28.9% [840 out of 2911] vs 26.2% [752 out of 2875]; P = .1). Index hospitalization costs were significantly higher for those undergoing SA ($52,556 vs $47,433; P < .001). Rates of readmission at 300 days were similar between patients receiving SA (43.8%) and no SA (42.8%; log-rank P = .3). The 3 most common causes of readmission were not different between groups and included heart failure (24.3% [594 out of 2444]; P = .6), infection (16.8% [411 out of 2444]; P = .5), and arrhythmia (11.7% [286 out of 2444]; P = .2).

Conclusions

In patients with nonparoxysmal atrial fibrillation, utilization of SA during CABG remains low. SA during CABG did not adversely influence mortality or short-term readmissions. These findings support increased use of SA during CABG.

Effect of cryothermic and radiofrequency Cox-Maze IV ablation on atrial size and function assessed by 2D and 3D echocardiography, a randomized trial. To freeze or to burn

BACKGROUND

Atrial linear scars in Cox-Maze IV procedures are achieved using Cryothermy (Cryo) or radiofrequency (RF) techniques. The subsequent postoperative left atrial (LA) reverse remodelling is unclear. We used 2- and 3-dimensional echocardiography (2-3DE) to compare the impact of Cryo and RF procedures on LA size and function 1 year after Cox-maze IV ablation concomitant with Mitral valve (MV) surgery.

METHODS

Seventy-two patients with MV disease and AF were randomized to Cryo (n = 35) or RF (n = 37) ablation. Another 33 patients were enroled without ablation (NoMaze). All patients underwent an echocardiogram the day before and 1 year after surgery. The LA function was assessed on 2D strain by speckle tracking and 3DE.

RESULTS

Forty-two ablated patients recovered sinus rhythm (SR) 1 year after surgery. They had comparable left and right systolic ventricular function, LA volume index (LAVI), and 2D reservoir strain before surgery. At follow-up, the 3DE extracted reservoir and booster function were higher after RF (37 ± 10% vs. 26 ± 6%; p < 0.001) than Cryo ablation (18 ± 9 vs. 7 ± 4%; p < 0.001), while passive conduit function was comparable between groups (24 ± 11 vs. 20 ± 8%; p = 0.17). The extent of LAVI reduction depended on the duration of AF preoperatively.

CONCLUSIONS

SR restoration after MV surgery and maze results in LA size reduction irrespective of the energy source used. Compared to RF, the extension of ablation area produced by Cryo implies a structural LA remodelling affecting LA systolic function.

Minimally Invasive Mitral Valve Surgery With Concomitant Cox Maze Procedure Is as Effective as a Median Sternotomy With Decreased Morbidity

OBJECTIVE

A right minithoracotomy (RMT) is a minimally invasive surgical approach that has been increasingly performed for the concomitant Cox maze IV procedure (CMP) and mitral valve surgery (MVS). Little is known regarding whether long-term rhythm and survival outcomes are affected by the RMT as compared with the traditional median sternotomy (MS) approach.

METHODS

Between April 2004 and April 2021, 377 patients underwent the concomitant CMP and MVS, of whom 38% had RMT. Propensity score matching yielded 116 pairs. Freedom from atrial tachyarrhythmias (ATA) was assessed with prolonged monitoring annually for 8 years. Survival, rhythm, and perioperative outcomes were compared.

RESULTS

The unmatched RMT cohort had a greater freedom from ATA recurrence at 1 year (99% vs 90%, P = 0.001) and 3 years (94% vs 86%, P = 0.045). The matched RMT cohort had longer cardiopulmonary bypass (median: 215 [199 to 253] vs 170 [136 to 198] min, P < 0.001) and aortic cross-clamp (110 [98 to 124] vs 86 [71 to 102] min, P < 0.001) times but shorter intensive care time (48 [24 to 95] vs 71 [26 to 144] h, P = 0.001) and length of stay (8 [6 to 11] vs 10 [7 to 14] h, P < 0.001). More pacemakers (18% vs 4%, P < 0.001) and postoperative transfusions (57% vs 41%, P = 0.014) occurred in the MS cohort. The 30-day mortality (P = 0.651) and 8-year survival (P = 0.072) was not significantly different between the cohorts.

CONCLUSIONS

Early 1-year and 3-year freedom from ATA recurrence was better in the RMT cohort compared with the MS cohort. Despite longer operative times, the RMT cohort had shorter lengths of stay, fewer postoperative transfusions, and fewer pacemakers placed.

Concomitant ablation of atrial fibrillation: New pacemakers and early rhythm recovery

OBJECTIVE

New permanent pacemaker (PPM) implantation after concomitant atrial fibrillation (AF) ablation has been associated with surgical ablation (SA). We sought to determine factors for PPM use as well as early rhythm recovery.

METHODS

From 2004 through 2019, 6135 patients underwent valve surgery and were grouped: No AF (n = 4584), AF no SA (n = 346), and AF with SA (n = 1205) to evaluate predischarge PPM and 3-month rhythm recovery (intrinsic heart rate >40 beats per minute).

RESULTS

Overall, 282 (4.6%) patients required a predischarge PPM: atrioventricular node dysfunction in 75.3%, sick sinus syndrome in 19.1%, both (5%), and indeterminate (0.7%). Patients with AF had more PPMs: AF with SA (7.9%) versus AF no SA (6.9%) versus No AF (3.6%) (P < .001). For patients with AF, PPM rates were not significantly higher for ablation patients (7.6% SA vs 6.9% AF no SA; P = .56). There were differences in PPM by SA lesion set (biatrial 12.8%; left atrial only 6.1%; pulmonary vein isolation 3.0%; P < .001). Among patients with AF treated with 3-month PPM follow-up, rhythm recovery was common (35 out of 62 [56.5%]) and did not differ by lesion set. Rhythm recovery was seen in 63 out of 141 (44.7%) in the atrioventricular node dysfunction group versus 24 out of 35 (68.6%) in the sick sinus syndrome group (P = .011). In propensity score-matched groups, late survival was similar (P = .63) for new PPM patients.

CONCLUSIONS

Avoiding conduction system trauma and delaying implantation reduces the need for postoperative PPM. Rhythm recovery within 3 months is frequent, especially for patients with sick sinus syndrome. A conservative approach to the implantation of a new PPMs is warranted.

A new procedure for elimination of atrial fibrillation associated with mitral valve disease: a proof-of-concept study

BACKGROUND

Left atrial enlargement and fibrosis have been linked to the pathogenesis of atrial fibrillation (AF). The authors aimed to introduce a novel concept and develop a new procedure for AF treatment based on these characteristics.

METHODS

The study included three stages. The first stage was a descriptive study to clarify the characteristics of the left atrial enlargement and fibrosis' distribution in patients with mitral valve disease and long-standing persistent AF. Based on these characteristics, the authors introduced a novel concept for AF treatment, and then translated it into a new procedure. The second stage was a proof-of-concept study with this new procedure. The third stage was a comparative effectiveness research to compare the clinical outcomes between patients with this new procedure and those who received Cox-Maze IV treatment.

RESULTS

Based on the nonuniform fashion of left atrial enlargement and fibrosis' distribution, the authors introduced a novel concept: reconstructing a left atrium with appropriate geometry and uniform fibrosis' distribution for proper cardiac conduction, and translated it into a new procedure: left atrial geometric volume reduction combined with left appendage base closure. As compared to the Cox-Maze IV procedure, the new procedure spent significantly shorter total surgery time, cardiopulmonary bypass time, and aortic cross-clamp time ( P <0.001). Besides, the new procedure was related to a shorter ICU stay period (odd ratio (OR)=0.45, 95% CI=0.26-0.78), lower costs (OR=0.15, 95% CI=0.08-0.29), and a higher rate of A wave of transmitral and transtricuspid flow reappearance (OR=1.76, 95% CI=1.02-3.04).

CONCLUSIONS

The new procedure is safe and effective for eliminating AF associated with mitral valve disease.

Performance of an Irrigated Bipolar Radiofrequency Ablation Clamp on Explanted Human Hearts

BACKGROUND

Bipolar radiofrequency (RF) clamps are commonly used during surgical ablation for atrial fibrillation (AF). This study examined the efficacy of an irrigated bipolar RF clamp to create transmural lesions in an ex vivo human heart model.

METHODS

Ten donor hearts, turned down for transplantation, were explanted and arrested with cold cardioplegia. The ablations of the Cox Maze IV procedure were performed using the Cardioblate LP (Medtronic, Inc) irrigated bipolar RF clamp. In the first 5 hearts, each lesion was created with a single application of RF, whereas in the remaining 5 hearts, each lesion was created with a double application of RF without unclamping. Each lesion was cross-sectioned and stained with 2,3,5-triphenyl-tetrazolium chloride to assess ablation depth and transmurality.

RESULTS

A total of 100 lesions were analyzed. In the single-ablation group, 222 of 260 sections (85%) and 37 of 50 lesions (74%) were transmural. The efficacy improved significantly in the double-ablation group, in which 348 of 359 sections (97%, P < .001) and 46 of 50 lesions (92%, P = .017) were transmural. Overall, in nontransmural lesions, the epicardial fat thickness was significantly greater (1.69 ± 0.70 mm vs 0.45 ±0.10 mm, P < .001) than the transmural lesions.

CONCLUSIONS

A single ablation on human atrial tissue with an irrigated bipolar RF clamp was insufficient to reliably create transmural lesions, but a double ablation significantly increased the lesion and section transmurality. Nontransmural lesions were associated with significantly thicker layers of epicardial fat, which likely decreased tissue energy delivery due to the higher resistance of fat to current flow.

Multicenter Study of Surgical Ablation for Atrial Fibrillation in Aortic Valve Replacement

There is controversy regarding appropriate surgical ablation procedures concomitant with nonmitral valve surgery. We retrospectively investigated the impact of surgical ablation for atrial fibrillation during aortic valve replacement between 2010 and 2015 in 16 institutions registered through the Japanese Society for Arrhythmia Surgery. Clinical data of 171 patients with paroxysmal and nonparoxysmal atrial fibrillation undergoing aortic valve replacement were collected and classified into full maze operation (n = 79), pulmonary vein isolation (PVI) (n = 56), and no surgical ablation (n = 36) groups. All patients were followed up and electrocardiograms were recorded in 68% at 2 years. The myocardial ischemia time was significantly longer in the maze group than the others during isolated aortic valve replacement (p ≤ 0.01), but there were no significant differences in 30-day or 2-year mortality rates between groups. The ratios of sinus rhythm at 2 years in paroxysmal and nonparoxysmal atrial fibrillation in the maze group versus PVI group were 87% versus 97%, respectively (p = 0.24) and 53% versus 42%, respectively (p = 0.47). No patients with nonparoxysmal atrial fibrillation in the no surgical ablation group maintained sinus rhythm at 2 years. In conclusion, both maze and PVI during aortic valve replacement are valuable strategies to restore sinus rhythm at 2 years and result in favorable early and midterm survival rates.

Clinical efficacy and safety of Cox-maze IV procedure for atrial fibrillation in patients with aortic valve calcification

Objective

Atrial fibrillation is associated with a high incidence of heart valve disease. There are few prospective clinical research comparing aortic valve replacement with and without surgical ablation for safety and effectiveness. The purpose of this study was to compare the results of aortic valve replacement with and without the Cox-maze IV procedure in patients with calcific aortic valvular disease and atrial fibrillation.

Methods

We analyzed one hundred and eight patients with calcific aortic valve disease and atrial fibrillation who underwent aortic valve replacement. Patients were divided into concomitant Cox maze surgery (Cox-maze group) and no concomitant Cox-maze operation (no Cox-maze group). After surgery, freedom from atrial fibrillation recurrence and all-cause mortality were evaluated.

Results

Freedom from all-cause mortality after aortic valve replacement at 1 year was 100% in the Cox-maze group and 89%, respectively, in the no Cox-maze group. No Cox-maze group had a lower rate of freedom from atrial fibrillation recurrence and arrhythmia control than those in the Cox-maze group (P = 0.003 and P = 0.012, respectively). Pre-operatively higher systolic blood pressure (hazard ratio, 1.096; 95% CI, 1.004–1.196; P = 0.04) and post-operatively increased right atrium diameters (hazard ratio, 1.755; 95% CI, 1.182–2.604; P = 0.005) were associated with atrial fibrillation recurrence.

Conclusion

The Cox-maze IV surgery combined with aortic valve replacement increased mid-term survival and decreased mid-term atrial fibrillation recurrence in patients with calcific aortic valve disease and atrial fibrillation. Pre-operatively higher systolic blood pressure and post-operatively increased right atrium diameters are associated with the prediction of recurrence of atrial fibrillation.

Barriers to atrial fibrillation ablation during mitral valve surgery

BACKGROUND

Nearly 40% of patients with atrial fibrillation (AF) undergoing mitral valve surgery do not receive concomitant ablation despite societal guidelines. We assessed barriers to implementation of this evidence-based practice through a survey of cardiac surgeons in 2 statewide quality collaboratives.

METHODS

Adult cardiac surgeons across 2 statewide collaboratives were surveyed on their knowledge and practice regarding AF ablation. Questions concerning experience, clinical practice, case scenarios, and barriers to implementation were included.

RESULTS

Among 66 respondents (66 of 135; 48.9%), the majority reported "very comfortable/frequently use" cryoablation (53 of 66; 80.3%) and radiofrequency (55 of 66; 83.3%). Only 12.1% (8/66) were not aware of the recommendations. Approximately one-half of the respondents reported learning AF ablation in fellowship (50.0%; 33 of 66) or attending courses (47.0%; 31 of 66). Responses to clinical scenarios demonstrated wide variability in practice patterns. One-half of the respondents reported no barriers; others cited increased cross-clamp time, excessive patient risk, and arrhythmia incidence as obstacles. Desired interventions included cardiology/electrophysiology support, protocols, pacemaker rate information, and education in the form of site visits, videos and proctors.

CONCLUSIONS

Knowledge of evidence-based recommendations and practice patterns vary widely. These data identify several barriers to implementation of concomitant AF ablation and suggest specific interventions (mentorship/support, protocols, research, and education) to overcome these barriers.

Clinical benefits of concomitant surgical ablation for atrial fibrillation in patients undergoing mitral valve surgery

BACKGROUND

The maze procedure is the dominant concomitant surgery performed with mitral valve (MV) surgery in patients with atrial fibrillation (AF). Most clinical recommendations regarding the maze procedure depend on the individual maze expert centers.

OBJECTIVE

The purpose of this study was to evaluate the clinical benefits of the maze procedure during MV surgery in a national cohort.

METHODS

Using the national health claims database established by the National Health Insurance Service of South Korea, data on subjects with AF who had undergone MV surgery from 2009 to 2017 were reviewed. The outcomes of interest were mortality; occurrence of ischemic or hemorrhagic stroke; hospitalization for bleeding events; and the composite of death, cerebrovascular accident, and major bleeding. Propensity score (PS) matching was performed for baseline adjustment.

RESULTS

Among 9501 subjects, the maze procedure was performed in 5508 (58.0%). In the PS-matched cohort (3376 pairs), the risk of the composite event was significantly lower in the maze group (hazard ratio [HR] 0.799; 95% confidence interval [CI] 0.731-0.873) than in the nonmaze group. The superiority of the maze procedure was similar for individual clinical events, including death (HR 0.795; 95% CI 0.711-0.889); ischemic stroke (HR 0.788; 95% CI 0.67-0.926); and major bleeding (HR 0.749; 95% CI 0.627-0.895), but not for hemorrhagic stroke (HR 0.984; 95% CI 0.768-1.262). In subgroup analyses of the composite events, these benefits were consistent among subjects aged ≥70 years or <70 years, surgery type (replacement vs repair), MV pathologies, and subjects with CHA₂DS₂-VASc score ≥4 or <4.

CONCLUSION

The addition of the maze procedure during MV surgery provided protective effects in the composite outcome of interest.

Superiority of complete bi-atrial ablation procedure for atrial fibrillation in rheumatic mitral valve disease

INTRODUCTION

The necessity of complete bi-atrial lesion created by radiofrequency clamp and pen for nonparoxysmal atrial fibrillation (AF) in patients with rheumatic mitral valve disease (RMVD) remains unclear.

METHODS

From January 2014 to December 2018, patients with RMVD concomitant with nonparoxysmal AF who underwent mitral valve surgery concomitant surgical ablation were retrospectively enrolled. We divided patients into Group A (complete bi-atrial lesion set created by radiofrequency clamp and pen) and Group B (simplified lesion sets created by radiofrequency clamp alone including bi-atrial ablation with incomplete mitral isthmus line and stand-alone left atrial ablation) according to the surgical ablation lesion sets. Propensity score matching was applied to analyze freedom from atrial tachyarrhythmias between the two groups.

RESULTS

Two hundred eight (38.5%) and 332 (61.5%) patients were divided into Group A and Group B, respectively. In Group B, the proportion of patients with recurrent atrial flutter in the subgroup of bi-atrial ablation with incomplete mitral isthmus line was higher than that in Group A (p = .044). After propensity score matching, there were 203 patients in each group. Better freedom from atrial tachyarrhythmias without antiarrhythmic drugs was obtained in Group A (83.1%, 79.6%, and 65.4%) than Group B (73.1%, 68.4%, and 52.7%) at 12, 36, and 60 months after operation (p = .012).

CONCLUSION

The application of radiofrequency clamp and pen to create complete bi-atrial lesion set in surgical ablation for nonparoxysmal AF in RMVD was associated with superior long-term efficacy.

Concomitant surgical ablation for atrial fibrillation is associated with increased risk of acute kidney injury but improved late survival

BACKGROUND

Acute kidney injury (AKI) after cardiac surgery remains a common complication that has been associated with increased morbidity and mortality. This study implemented Kidney Disease Improving Global Outcomes criteria to evaluate renal outcomes after concomitant surgical ablation for atrial fibrillation.

METHODS

Patients with a history of atrial fibrillation who underwent elective cardiac surgery at our institution from 2008 to 2018 were retrospectively reviewed. Those with preoperative renal dysfunction were excluded. Patients were classified as those who underwent concomitant Cox-Maze IV (CMP-IV) (n = 376) or no surgical ablation (n = 498). Nearest neighbor 1:1 propensity matching was conducted on fourteen covariates. AKI was evaluated by mixed effects logistic regression analysis. Long-term survival was evaluated by proportional hazards regression.

RESULTS

Propensity matching yielded 308 patients in each group (n = 616). All preoperative variables were similar between groups. The concomitant CMP-IV group had a greater incidence of AKI: 32% (n = 99) versus 16% (n = 49), P &lt; .001. After accounting for bypass time and nonablation operations on mixed effects analysis, concomitant CMP-IV was associated with increased risk of AKI (odds ratio, 1.89; confidence interval, 1.12-3.18; P = .017). While AKI was associated with decreased late survival (P &lt; .001), patients who received a concomitant CMP-IV maintained superior 7-year survival to patients who received no ablation (P &lt; .001). No patients required permanent dialysis.

CONCLUSIONS

Concomitant CMP-IV was independently associated with increased risk of AKI in the acute postoperative period. However, the long-term risks of AKI were offset by the significant survival benefit of CMP-IV. Concerns regarding new-onset renal dysfunction should not prohibit recommendation of this procedure in appropriate patients.

Bi-atrial versus left atrial ablation for patients with rheumatic mitral valve disease and non-paroxysmal atrial fibrillation (ABLATION): rationale, design and study protocol for a multicentre randomised controlled trial

INTRODUCTION

Atrial fibrillation (AF) is common in patients with rheumatic mitral valve disease (RMVD) and increase the risk of stroke and death. Bi-atrial or left atrial ablation remains controversial for treatment of AF during mitral valve surgery. The study aims to compare the efficacy and safety of bi-atrial ablation with those of left atrial ablation among patients with RMVD and persistent or long-standing persistent AF.

METHODS AND ANALYSIS

The ABLATION trial (Bi-atrial vs Left Atrial Ablation for Patients with RMVD and Non-paroxysmal AF) is a prospective, multicentre, randomised controlled study. The trial will randomly assign 320 patients with RMVD and persistent or long-standing persistent AF to bi-atrial ablation procedure or left atrial ablation procedure in a 1:1 randomisation. The primary end point is freedom from documented AF, atrial flutter or atrial tachycardia of >30 s at 12 months after surgery off antiarrhythmic drugs. Key secondary end point is the probability of freedom from permanent pacemaker implantation at 12 months after surgery. Secondary outcomes include the probability of freedom from any recurrence of atrial tachyarrhythmias with antiarrhythmic drugs, AF burden, incidence of adverse events and cardiac function documented by echocardiography at 12 months after operation.

ETHICS AND DISSEMINATION

The central ethics committee at Fuwai Hospital approved the ABLATION trial. The results of this study will be disseminated through publications in peer-reviewed journals and conference presentations.

TRIAL REGISTRATION NUMBER

NCT05021601.

Complete Left-Atrial Lesion Set versus Pulmonary Vein Isolation Only in Patients with Paroxysmal AF Undergoing CABG or AVR

Background and Objectives: In patients with paroxysmal atrial fibrillation (AF) undergoing CABG or aortic valve surgery, many surgeons are not willing to open the left atrium to perform a complete left-sided Cox-Maze lesion set. Pulmonary vein isolation (PVI) is often favored in those patients. We investigated the outcome of patients with isolated pulmonary vein isolation compared to those receiving an extended left atrial (LA) lesion set. Materials and Methods: Between 2003 and 2016, 817 patients received concomitant surgical AF ablation in our institution. A total of 268 patients with paroxysmal AF were treated by surgical ablation concomitant to AVR or CABG. Of those, 86 patients underwent a complete left-sided lesion set, while 182 patients were treated with an isolated pulmonary vein isolation. The primary endpoint was freedom from atrial fibrillation at 12 months' follow-up. Results: There were no statistically significant differences regarding baseline characteristics. No major ablation-related complications were observed in any of the groups. In the PVI group, three patients (1.6%) had an intraoperative stroke, while two (2.3%) patients experienced a stroke in the LA ablation group (p = 0.98). In-hospital mortality was 3.4% in the PVI group, and 2.8% in the extended LA group (p = 0.33). Freedom from AF at 12 months' follow-up was 76% in the extended LA ablation group and 70% in the PVI group, showing no statistically significant difference (p = 0.32). Conclusion: Surgical AF ablation concomitant to CABG or AVR in patients with paroxysmal AF is safe and effective. There was no statistically significant difference between the compared lesion sets in terms of freedom from AF, survival or stroke rate after 12 months.

Comparing mid-term outcomes of Cox-Maze procedure and pulmonary vein isolation for atrial fibrillation after concomitant mitral valve surgery: A systematic review

BACKGROUND

Although concomitant pulmonary vein isolation (PVI) is used more frequently than the Cox-Maze procedure, which is currently the gold standard treatment for atrial fibrillation (AF), data on the comparative effectiveness of the two procedures after concomitant mitral valve (MV) surgery are still limited.

OBJECTIVE

We conducted a systematic review to identify randomized controlled trials (RCTs) and observational studies comparing the mid-term mortality and recurrence of AF after concomitant Cox-Maze and PVI in patients with AF undergoing MV surgery based on 12-month follow-up.

METHODS

Medline, EMBASE databases, and the Cochrane Library were searched from 1987 up to March 2022 for studies comparing concomitant Cox-Maze and PVI. Additionally, a meta-analysis of RCTs was performed to compare the mid-term clinical outcomes between these two surgical ablation techniques.

RESULTS

Three RCTs and three observational studies meeting the inclusion criteria were included in this systematic review with 790 patients in total (532 concomitant Cox-Maze and 258 PVI during MV surgery). Most studies reported that the concomitant Cox-Maze procedure was associated with higher freedom from AF at 12-month follow-up than PVI. Regarding AF recurrence, estimates pooled across the three RCTs indicated large heterogeneity and high uncertainty. In the largest and highest quality RCT, 12-month AF recurrence was higher in the PVI arm (risk ratio = 1.58, 95% CI: 0.91-2.73). In two out of three higher-quality observational studies, 12-month AF recurrence was higher in PVI than in the Cox-Maze arm (estimated adjusted probabilities 11% vs. 8% and 35% vs. 17%, respectively). RCTs demonstrated comparable 12-month mortality between concomitant Cox-Maze and PVI, while observational studies demonstrated the survival benefit of Cox-Maze.

CONCLUSIONS

Concomitant Cox-Maze in AF patients undergoing MV surgery is associated with better mid-term freedom from AF when compared to PVI with comparable mid-term survival. Large observational studies suggest that there might be a mid-term survival benefit among patients after concomitant Cox-Maze. Further large RCTs with longer standardized follow-up are required to clarify the benefits of concomitant Cox-Maze in AF patients during MV surgery.

Prophylactic Left Atrial Appendage Exclusion in Cardiac Surgery Patients With Elevated CHA2DS2-VASc Score: Results of the Randomized ATLAS Trial

OBJECTIVE

Patients with elevated CHA₂DS₂-VASc scores are at high risk for atrial fibrillation (AF) and thromboembolic events (TE) after cardiac surgery. Left atrial appendage exclusion (LAAE) is a permanent, continuous approach to stroke prevention in AF, overcoming limitations of oral anticoagulation (OAC). We report ATLAS trial results focused on LAAE technical success and perioperative safety and TE rates with and without LAAE in cardiac surgery patients who developed postoperative AF (POAF).

METHODS

ATLAS (NCT02701062) was a prospective, multicenter, feasibility trial. Patients age ≥18 years, undergoing structural heart procedure, with no preoperative AF, CHA₂DS₂-VASc ≥2, and HAS-BLED ≥2 were randomized 2:1 to LAAE or no LAAE. Patients who developed POAF and/or received LAAE were followed for 1 year. LAAE was evaluated with intraoperative transesophageal echocardiography.

RESULTS

A total of 562 patients were randomized to LAAE (n = 376) or no LAAE (n = 186). Mean CHA₂DS₂-VASc (3.4 vs 3.4) and HAS-BLED (2.8 vs 2.9) scores were similar for LAAE and no LAAE groups. LAAE success (no flow nor residual stump >10 mm) was 99%. One LAAE-related serious adverse event (0.27%) occurred and was resolved without sequelae. There were 44.3% of patients who developed POAF. Through 1 year, 3.4% of LAAE patients and 5.6% of no LAAE patients had TE. OAC was used by 32.5% of POAF patients. Bleeding was higher with OAC than without (16.1% vs 5.4%, P = 0.008).

CONCLUSIONS

ATLAS demonstrated a high rate of successful LAAE with low LAAE-related serious adverse events in cardiac surgery patients. Study results should be considered in future trial design to further evaluate prophylactic LAAE for stroke prevention in cardiac surgery patients with elevated stroke risk.

Anterior Pathway for Epicardial Left Atrial Appendage Clip Occlusion During Minimally Invasive Atrioventricular Valve Surgery

The left atrial appendage occlusion (LAAO) by endocardial suture is sometimes inadequate and thrombogenic with uncertain electrical competence. Moreover, epicardial LAAO clip placement through the transverse sinus can be technically challenging during minimally invasive atrioventricular valve surgery. Here, we describe our new endoscopic technique via an anterior access pathway in 5 patients with concomitant atrial fibrillation using an epicardial clip device (AtriClip Pro 1 or AtriClip Pro 2, AtriCure, Mason, OH, USA) for LAAO. The LAAO was successful in all patients without residual perfusion and surgical complications. Epicardial LAAO by clip via the anterior access pathway represents a novel and feasible endoscopic technique for minimally invasive atrioventricular valve surgery.

Efficacy of a Novel Bipolar Radiofrequency Clamp: An Acute Porcine Model

OBJECTIVE

Expert consensus guidelines recommend surgical ablation (SA) for patients with symptomatic atrial fibrillation (AF), but less than half of patients with AF undergoing cardiac procedures receive concomitant SA. Complete isolation of the left atrial posterior wall (LAPW) has been shown to be the most critical part of the Cox maze procedure. The purpose of this study was to investigate the performance of a novel radiofrequency (RF) bipolar device, EnCompass™ (AtriCure, Inc., Mason, OH, USA), designed to isolate the LAPW in a single application.

METHODS

Five adult pigs underwent SA in a beating heart model. After a single ablation, the heart was arrested, explanted, and stained with triphenyl-tetrazolium-chloride for histological assessment. Each lesion was sectioned, and the ablation depth, muscle, and fat thickness were determined. The lesion width, energy delivery, and ablation times were compared with those from a reference RF clamp (Synergy™, AtriCure).

RESULTS

Transmurality was documented in 100% of lesions (5 of 5) and cross sections (160 of 160). Electrical isolation was documented in every instance. There was no evidence of clot, charring, or pulmonary vein stenosis. Compared with the reference clamp, the lesions created by the EnCompass™ clamp were 1.5 times wider on average. The average energy delivered was 5 times higher over a duration that was 4.5 times longer due to the increased volume of tissue ablated.

CONCLUSIONS

The EnCompass™ clamp reproducibly created transmural isolation of the LAPW with a single application. This may allow for simplification of the SA strategy and increased adoption of AF treatment during concomitant surgery.

Commentary to: "Comparing midterm outcomes" of Cox-Maze procedure and pulmonary vein isolation for atrial fibrillation after concomitant mitral valve surgery: A "systematic review"

There is no solid evidence from the literature that compare Cox-Maze with pulmonary vein isolation techniques for atrial fibrillation in the context of concomitant mitral valve surgery. Although the first is perhaps more effective and linked to higher freedom from atrial fibrillation, it is more invasive compared to the pulmonary isolation.