Surgical ablation of atrial fibrillation in patients with heart failure

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.

How to establish a successful and sustainable surgical atrial fibrillation program: key considerations on the arrhythmia, training and treatment strategies

Establishing a successful and sustaining atrial fibrillation (AF) program should be current standard of care in cardiac surgery by providing not only sinus rhythm restoration but improving survival significantly. Recognition of AF as a serious cardiac disease impacting a considerable number of patients in terms of stroke, heart failure development and mortality is key when implementing a protocol to identify patients suitable for surgical ablation and a treatment standard according to the underlying pathology. The ablation strategy resulting in the best potential rhythm outcome should be chosen, and the applied access should follow this decision in a way that the optimal lesion set can be executed completely. A thorough follow-up is required to confirm results or make necessary adjustments to the implemented treatment protocol. This should be done in close collaboration with other treatment specialists such as cardiologists, electrophysiologists, primary care physicians, or neurologists. This collaboration might also facilitate an expansion of the program towards stand-alone ablation, ventricular tachycardia ablation, and inappropriate sinus tachycardia ablation.

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.

Prediction model of atrial fibrillation recurrence after Cox-Maze IV procedure in patients with chronic valvular disease and atrial fibrillation based on machine learning algorithm

OBJECTIVES

Atrial fibrillation (AF) is a prevalent cardiac arrhythmia, and Cox-maze IV procedure (CMP-IV) is a commonly employed surgical technique for its treatment. Currently, the risk factors for atrial fibrillation recurrence following CMP-IV remain relatively unclear. In recent years, machine learning algorithms have demonstrated immense potential in enhancing diagnostic accuracy, predicting patient outcomes, and devising personalized treatment strategies. This study aims to evaluate the efficacy of CMP-IV on treating chronic valvular disease with AF, utilize machine learning algorithms to identify potential risk factors for AF recurrence, construct a CMP-IV postoperative AF recurrence prediction model.

METHODS

A total of 555 patients with AF combined with chronic valvular disease, who met the criteria, were enrolled from January 2012 to December 2019 from the Second Xiangya Hospital of Central South University and the Affiliated Xinqiao Hospital of the Army Medical University, with an average age of (57.95±7.96) years, including an AF recurrence group (n=117) and an AF non-recurrence group (n=438). Kaplan-Meier method was used to analyze the sinus rhythm maintenance rate, and 9 machine learning models were developed including random forest, gradient boosting decision tree (GBDT), extreme gradient boosting (XGBoost), bootstrap aggregating, logistic regression, categorical boosting (CatBoost), support vector machine, adaptive boosting, and multi-layer perceptron. Five-fold cross-validation and model evaluation indicators [including F1 score, accuracy, precision, recall, and area under the curve (AUC)] were used to evaluate the performance of the models. The 2 best-performing models were selected for further analyze, including feature importance evaluation and Shapley additive explanations (SHAP) analysis, identifying AF recurrence risk factors, and building an AF recurrence risk prediction model.

RESULTS

The 5-year sinus rhythm maintenance rate for the patients was 82.13% (95% CI 78.51% to 85.93%). Among the 9 machine learning models, XGBoost and CatBoost models performed best, with the AUC of 0.768 (95% CI 0.742 to 0.786) and 0.762 (95% CI 0.723 to 0.801), respectively. Feature importance and SHAP analysis showed that duration of AF, preoperative left ventricular ejection fraction, postoperative heart rhythm, preoperative neutrophil-to-lymphocyte ratio, preoperative left atrial diameter, preoperative heart rate, and preoperative white blood cell were important factors for AF recurrence. Conclusion: Machine learning algorithms can be effectively used to identify potential risk factors for AF recurrence after CMP-IV. This study successfuly constructs 2 prediction model which may enhance individualized treatment plans.

Machine learning-based analysis of risk factors for atrial fibrillation recurrence after Cox-Maze IV procedure in patients with atrial fibrillation and chronic valvular disease: A retrospective cohort study with a control group

Objectives

To evaluate the efficacy of the Cox-Maze IV procedure (CMP-IV) in combination with valve surgery in patients with both atrial fibrillation (AF) and valvular disease and use machine learning algorithms to identify potential risk factors of AF recurrence.

Methods

A total of 1,026 patients with AF and valvular disease from two hospitals were included in the study. 555 patients received the CMP-IV procedure in addition to valve surgery and left atrial appendage ligation (CMP-IV group), while 471 patients only received valve surgery and left atrial appendage ligation (Non-CMP-IV group). Kaplan-Meier analysis was used to calculate the sinus rhythm maintenance rate. 58 variables were selected as variables for each group and 10 machine learning models were developed respectively. The performance of the models was evaluated using five-fold cross-validation and metrics including F1 score, accuracy, precision, and recall. The four best-performing models for each group were selected for further analysis, including feature importance evaluation and SHAP analysis.

Results

The 5-year sinus rhythm maintenance rate in the CMP-IV group was 82.13% (95% CI: 78.51%, 85.93%), while in the Non-CMP-IV group, it was 13.40% (95% CI: 10.44%, 17.20%). The eXtreme Gradient Boosting (XGBoost), LightGBM, Category Boosting (CatBoost) and Random Fores (RF) models performed the best in the CMP-IV group, with area under the curve (AUC) values of 0.768 (95% CI: 0.742, 0.786), 0.766 (95% CI: 0.744, 0.792), 0.762 (95% CI: 0.723, 0.801), and 0.732 (95% CI: 0.701, 0.763), respectively. In the Non-CMP-IV group, the LightGBM, XGBoost, CatBoost and RF models performed the best, with AUC values of 0.738 (95% CI: 0.699, 0.777), 0.732 (95% CI: 0.694, 0.770), 0.724 (95% CI: 0.668, 0.789), and 0.716 (95% CI: 0.656, 0.774), respectively. Analysis of feature importance and SHAP revealed that duration of AF, preoperative left ventricular ejection fraction, postoperative heart rhythm, preoperative neutrophil-lymphocyte ratio, preoperative left atrial diameter and heart rate were significant factors in AF recurrence.

Conclusion

CMP-IV is effective in treating AF and multiple machine learning models were successfully developed, and several risk factors were identified for AF recurrence, which may aid clinical decision-making and optimize the individual surgical management of AF.

Hybrid ablation of persistent and long-standing persistent atrial fibrillation with depressed ejection fraction: A single-center observational study

OBJECTIVE

The relationship between atrial fibrillation (AF) and heart failure with depressed ejection fraction (EF) is complex. AF-related tachycardia-mediated cardiomyopathy (TMC) can lead to worsening EF and clinical heart failure. We sought to determine whether a hybrid team ablation approach (HA) can be performed safely and restore normal sinus rhythm in patients with TMC and heart failure and to delineate the effect on heart failure.

METHODS

We retrospectively analyzed patients with nonparoxysmal (ie, persistent and long-standing persistent) AF-related TMC with depressed left ventricular EF (LVEF ≤40%) and heart failure (New York Heart Association [NYHA] class ≥2) who underwent HA between 2013 and 2018 and had at least 1 year of follow-up. Pre-HA and post-HA echocardiograms were compared for LVEF and left atrial (LA) size. Rhythm success was defined as <30 seconds in AF/atrial flutter/atrial tachycardia without class I or III antiarrhythmic drugs. Results are expressed as mean ± SD and 95% confidence interval (CI) of the mean.

RESULTS

Forty patients met the criteria for inclusion in our analysis. The mean patient age was 67 ± 9.4 years. The majority of patients had long-standing persistent AF (26 of 40; 65%), and the remainder had persistent AF (14 of 40; 35%). All patients had NYHA class II or worse heart failure (NYHA class II, 36 of 40 [90%]; NYHA class III, 4 of 40 [10%]). The mean time in AF pre-HA was 5.6 ± 6.7 years. All patients received both HA stages. No deaths or strokes occurred within 30 days. Three new permanent pacemakers (7.5%) were placed. Rhythm success was achieved in >60% of patients during a mean 3.5 ± 1.9 years of follow-up. LVEF improved significantly by 12.0% ± 12.5% (95% CI, 7.85%-16.0%; P < .0001), and mean LA size decreased significantly by 0.40 cm ± 0.85 cm (95% CI, 0.69-0.12 cm; P < .01), with a mean of 3.0 ± 1.5 years between pre-HA and post-HA echocardiography. NYHA class improved significantly after HA (mean pre-HA NYHA class, 2.1 ± 0.3 [95% CI, 2.0-2.2]; mean post-HA NYHA class, 1.5 ± 0.6 [95% CI, 1.3-1.7]; P < .0001).

CONCLUSIONS

Thoracoscopic HA of AF in selected patients with TMC heart failure is safe and can result in rhythm success with structural heart changes, including improvements in LVEF and LA size.

The Convergent Procedure for AF: A Surgeon's Perspective

The Converge IDE Trial demonstrated improved patient outcomes in a challenging persistent and long-standing persistent atrial fibrillation population using a heart team hybrid approach with epicardial and endocardial staged ablations. Surgeons encounter unique circumstances with the surgical epicardial stage of the Convergent procedure which include unfamiliarity with left atrial posterior anatomy, endoscopic/thoracoscopic visualization, minimally invasive left atrial appendage management and expanded indications for the procedure. Overcoming these unique challenges is key to the adoption of the Convergent procedure as a critical off-pump approach that should be part of the surgical armamentarium in the treatment of atrial fibrillation. This article is protected by copyright. All rights reserved.