Impact of Atrial Fibrillation Duration on the Success of First-Time Concomitant Cox Maze Procedures

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.

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.

Higher F-wave frequency associates with poor procedural success rate after Maze procedure

OBJECTIVES

Persistent atrial fibrillation (AF) causes atrial remodeling, which causes myocardial fibrosis and micro-reentry. Fibrosis may reduce wave voltage and micro-reentry may enhance the dominant frequency (DF) of the F-wave. We investigated whether the DF predicts procedural success by the Maze procedure.

METHODS

In 138 consecutive patients who underwent mitral valve surgery and a modified Cox-Maze III procedure for persistent AF in Nagoya University in 2002-2018, 96 (70%) were successfully cardioverted (group S); 42 had persistent or relapsed AF after surgery (group F). Patient data were compared between the groups. Cut-off values were determined by an ROC analysis and predictors of procedural success were evaluated. The DF was obtained from the F-wave of V1 by a high-speed Fourier analysis using the CEPAS software program.

RESULTS

Group F showed a significantly larger LA diameter, better LVEF, lower F-wave voltage, higher DF, and longer duration of AF. The cut-off values were as follows: LA diameter, 56 mm; EF, 64.5%; F-wave voltage, 0.13 mV; DF, 7.3 Hz; and duration of AF, 44 months. Each factor showed statistical significance in a univariate analysis; DF lost significance in the multivariate analysis. The higher (DF ≥ 7.3 Hz) and lower voltage group (≤ 0.13 mV) showed the worst procedural success rate (36%), while the lower DF (< 7.3 Hz) and higher voltage group (> 0.13 mV) showed a good rate (86%).

CONCLUSIONS

The DF of the F-wave is a useful predictor of procedural success after the Maze procedure in addition to the voltage of F-wave.

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.

Case Report: The Cox-Maze IV Procedure in the Mirror: The Use of Three-Dimensional Printing for Pre-operative Planning in a Patient With Situs Inversus Dextrocardia

The safety and efficacy of the Cox-Maze IV procedure (CMP-IV) for situs inversus dextrocardia patients with atrial fibrillation is yet to be determined. Herein, we present the case of a 39-year-old male patient admitted to our cardiac center following progressive exertional dyspnea. The patient was diagnosed with situs inversus dextrocardia, severe mitral regurgitation, and paroxysmal atrial fibrillation. A three-dimensional (3D) heart model printing device embedded with designated ablation lines was used for pre-operative planning. Mitral valvuloplasty, CMP-IV, and tricuspid annuloplasty were performed. The patient had an uneventful recovery and was in sinus rhythm during a 12-month follow-up period using a 24-h Holter monitoring device. The case herein is one of the first to report on adopting the CMP-IV procedure for situs inversus dextrocardia patients with complex valvuloplasty operation. In addition, the 3D printing technique enabled us to practice the Cox-maze IV procedure, given the patient's unique cardiac anatomy.

Left Atrial Appendage Exclusion in Atrial Fibrillation Radiofrequency Ablation during Mitral Valve Surgery: A Single-Center Experience

Background

Atrial fibrillation surgical radiofrequency ablation (AFSA) during mitral valve surgery (MVS) has almost completely superseded the Cox-Maze procedure for the treatment of atrial fibrillation.

Methods

We retrospectively analyzed 100 patients who underwent MVS + AFSA in our institution from January 2008 to June 2017. We compared the effectiveness of AFSA in patients who underwent LAA exclusion to those who did not. Moreover, we analyzed the role of preoperative AF duration (≤ or >1 year) and medial-lateral left atrial dimensions (ML-LAD) (≤ or >6 cm). The efficacy endpoint was freedom from AF at discharge and at 2-year follow-up. The safety endpoints were need of a permanent pacemaker (PMK), surgical re-exploration, occurrence of stroke, and left circumflex artery or esophageal lesions.

Results

Overall, the rate of AF freedom was 69% at discharge and 80% at 2-year follow-up. LAA exclusion did not influence AF freedom at 2-year follow-up, and 84.6% of patients who underwent LAA exclusion were in the sinus rythm (SR) at 2 year compared to 75% of those who did not receive LAA exclusion free from AF as well (p=0.230). AF duration ≤1 or >1 year did not influence sinus rhythm (SR) maintenance (85.7% vs. 75.8%; p=0.224), and in these two groups, LAA exclusion did not change the efficacy of AFSA. ML-LAD ≤ 6 cm was associated with better results in terms of SR maintenance. A statistically significant association between LAA exclusion and SR maintenance at 2-year follow-up (p=0.017) was found among patients with ML-LAD ≤ 6 cm. Complications included 7 cases of PMK implantation, 2 cases of surgical re-exploration, and 1 case of stroke. No circumflex artery or esophageal lesions occurred after surgical procedures.

Conclusions

In our experience, AFSA during isolated MVS resulted in good outcomes in terms of SR maintenance and incidence of complications. AF duration ≤ 1 year did not influence results, while patients with ML-LAD ≤ 6 cm had significantly better results regarding SR at follow-up. In patients with ML-LAD ≤ 6 cm, LAA exclusion significantly increased the success rate of SR maintenance at 2-year follow-up.

Novel risk score for predicting recurrence of atrial fibrillation after the Cryo-Maze procedure

OBJECTIVES

This study aimed to develop a novel risk score model for quantitative prediction of the rate of atrial fibrillation (AF) recurrence after the Cryo-Maze procedure in patients with persistent AF.

METHODS

We enrolled 450 consecutive patients who underwent the Cryo-Maze procedure for persistent AF concomitant with other cardiac procedures in our institute between 2001 and 2019. We randomly divided the cohort into two groups. We derived a model in a 'development cohort' (270 patients; 60%) and validated it in a 'test cohort' (180 patients; 40%) by receiver operating characteristic curve analysis.

RESULTS

The median follow-up was 5.2 (interquartile range: 2.0-9.9) years. The 1-, 5-, 10- and 15-year rates of freedom from AF recurrence in the entire cohort were 91.4%, 83.5%, 76.2% and 57.1%, respectively. Risk factors for AF recurrence examined by logistic regression analysis included F-wave voltage in V1 < 0.2 mV, preoperative AF duration >5 years and left atrial volume index >100 ml/m2. Points were assigned to each risk factor according to its odds ratio. A novel risk score model was developed using these three variables and age, with a range up to 10 points. High score (>7) predicted high rates of AF recurrence after the Cryo-Maze procedure. The area under the receiver operating characteristic curve of the novel risk model score was 0.78 (95% confidence interval: 0.65-0.91) in the test cohort.

CONCLUSIONS

Use of the Cryo-Maze procedure should be carefully considered in patients with a higher model score because of a higher risk of AF recurrence.

Persistent atrial fibrillation over 3 years is associated with higher recurrence after catheter ablation

Instruction

Longer atrial fibrillation (AF) durations have higher recurrence rates after rhythm control. However, there is limited data on the effect of the AF duration on recurrence after atrial fibrillation catheter ablation (AFCA). In the present study, we investigated the rhythm outcome of AFCA according to the AF duration based on the first electrocardiogram (ECG) diagnosis.

Methods and Results

We included 1005 patients with AF (75% male, 59 ± 11 years old) who underwent AFCA and whose first ECG diagnosis time point was evident. The clinical characteristics and rhythm outcomes were compared based on the AF duration (≤3 years, n = 537; >3 years, n = 468) and AF burden (paroxysmal atrial fibrillation [PAF], n = 387; persistent atrial fibrillation [PeAF], n = 618). Longer AF durations were associated with older age (P = .020), larger left atrial size (P = .009) and a higher number of patients with hypertension (P < .001) or PeAF (P < .001). During 24 ± 22 months of follow‐up, the postablation clinical recurrence rate was higher in patients with a longer AF duration (logrank P = .002). The AF recurrence rate was significantly higher in PeAF patients with an AF duration >3 years (logrank P = 0.009), but not in subjects with PAF (logrank P = .939). In a multivariate Cox regression analysis, a longer AF duration was significantly associated with a higher clinical recurrence rate after AFCA in PeAF patients (adjusted hazard ratio, 1.06; range, 1.03‐0.10; P = 0.001), but not PAF.

Conclusion

Although longer AF duration was associated with higher clinical recurrence rates after AFCA, the rate was significant in patients with PeAF lasting >3 years, but not in PAF patients.

Concomitant Cardiac Surgery and Radiofrequency Ablation of Atrial Fibrillation: A Retrospective Single Center Study

OBJECTIVES

Concomitant cardiac surgery and radiofrequency atrial fibrillation (AF) ablation is an established procedure recommended in guidelines. However, the results have not been as good as expected. The authors therefore searched for predictive factors of success of the ablation procedure.

DESIGN

The authors carried out a retrospective cohort study.

SETTING

All the included patients had cardiac surgery in the Dijon University Hospital.

PARTICIPANTS

One hundred sixty-three patients with AF underwent a concomitant radiofrequency ablation between January 2009 and December 2016.

INTERVENTIONS

A radiofrequency device was used to isolate the pulmonary veins creating a "Box lesion."

MEASUREMENTS AND MAIN RESULTS

The primary endpoint of the study was freedom from AF at 12 months with follow-up assessed by an electrocardiogram or a 24-hour recording electrocardiogram Holter. The patient's mean age was 71 ± 9 years with a sex ratio of 1.4. Sixty-six percent of patients had paroxysmal AF and 34% nonparoxysmal AF, which includes persistent and long-standing persistent AF. Sixty-one percent of patients had an AF history for more than 1 year. The mean left atrial diameter was 47 ± 10 mm. No major ablation complications related to the procedure occurred. Overall freedom from AF rate after 1-year follow-up was 60% (n = 98). Six patients (4%) received an additional catheter-based ablation, and 10 patients (6%) had an electrical cardioversion during the follow-up period. The authors identified preoperative paroxysmal AF (odds ratio [OR] 2.54 [1.27-5.14] p = 0.008) and recent history of AF, less than 1 year, (OR 1.99 [1-4.06] p = 0.05) as statistically significant predictors for sinus rhythm maintenance at the 12-month follow-up. At the 12-month follow-up, 64% of patients who had concomitant epicardial treatment were in sinus rhythm and 57% of patients were in sinus rhythm after endocardial treatment. There were no significant differences in rhythm outcome between epicardial and endocardial radiofrequency approach, or between surgical procedures (mitral valve replacement versus coronary artery bypass grafting). The authors could not identify in a univariate analysis a significant left atrium size cutoff upon which ablation was less likely to be successful at 12 months follow-up.

CONCLUSIONS

Concomitant cardiac surgery and radiofrequency AF ablation provided freedom from AF for 60% of patients after 1-year follow-up. The authors have shown that paroxysmal AF and recent AF are predictive factors of success. Nevertheless, thorough postoperative care is necessary to improve long-term results, including the use of additional catheter ablation or cardioversion.

Outcomes of Surgical Ablation in Patients With Atrial Fibrillation Undergoing Cardiac Surgeries

BACKGROUND

Surgical ablation procedure is commonly performed in patients with atrial fibrillation (AF) undergoing cardiac surgeries; however, the evidence regarding its impact on in-hospital cardiovascular outcomes is controversial.

METHODS

We queried the Nationwide Inpatient Sample Database for patients with AF who underwent cardiac surgeries from 1998 to 2013. We performed a propensity-score matching including 21 various baseline characteristics to compare those who underwent surgical ablation with those who had not.

RESULTS

A total of 47,964 hospitalizations were included in our final analysis. On propensity matching, 23,975 were in the surgical ablation group and 23,990 in the control group. The primary outcome of in-hospital mortality was lower in the surgical ablation group compared with the control group (3.6% versus 4.2%, p < 0.001). The surgical ablation group was associated with lower in-hospital cerebrovascular accident (2.0% versus 2.8%, p < 0.001), cardiogenic shock (2.6% versus 3.6%, p < 0.001), use of intraaortic balloon pump (5.1% versus 5.8%, p = 0.001), and shorter length of hospital stay (12.3 ± 10.1 versus 12.5 ± 10.3 days, p = 0.008). There was no difference between the surgical ablation and control groups in the incidence of cardiac tamponade (0.4% versus 0.3%, p = 0.296). The surgical ablation group was associated with a higher rate of complete heart block (5.2% versus 4.3%, p < 0.001) and permanent pacemaker insertion (8.6% versus 8.0%, p = 0.01).

CONCLUSIONS

In this large analysis of almost 50,000 patients with AF undergoing cardiac surgery, surgical ablation appears to be safe in the short term. Future studies should focus on evaluating the long-term effectiveness of this procedure.

The Society of Thoracic Surgeons 2017 Clinical Practice Guidelines for the Surgical Treatment of Atrial Fibrillation

EXECUTIVE SUMMARY

Surgical ablation for atrial fibrillation (AF) can be performed without additional risk of operative mortality or major morbidity, and is recommended at the time of concomitant mitral operations to restore sinus rhythm. (Class I, Level A) Surgical ablation for AF can be performed without additional operative risk of mortality or major morbidity, and is recommended at the time of concomitant isolated aortic valve replacement, isolated coronary artery bypass graft surgery, and aortic valve replacement plus coronary artery bypass graft operations to restore sinus rhythm. (Class I, Level B nonrandomized) Surgical ablation for symptomatic AF in the absence of structural heart disease that is refractory to class I/III antiarrhythmic drugs or catheter-based therapy or both is reasonable as a primary stand-alone procedure, to restore sinus rhythm. (Class IIA, Level B randomized) Surgical ablation for symptomatic persistent or longstanding persistent AF in the absence of structural heart disease is reasonable, as a stand-alone procedure using the Cox-Maze III/IV lesion set compared with pulmonary vein isolation alone. (Class IIA, Level B nonrandomized) Surgical ablation for symptomatic AF in the setting of left atrial enlargement (≥4.5 cm) or more than moderate mitral regurgitation by pulmonary vein isolation alone is not recommended. (Class III no benefit, Level C expert opinion) It is reasonable to perform left atrial appendage excision or exclusion in conjunction with surgical ablation for AF for longitudinal thromboembolic morbidity prevention. (Class IIA, Level C limited data) At the time of concomitant cardiac operations in patients with AF, it is reasonable to surgically manage the left atrial appendage for longitudinal thromboembolic morbidity prevention. (Class IIA, Level C expert opinion) In the treatment of AF, multidisciplinary heart team assessment, treatment planning, and long-term follow-up can be useful and beneficial to optimize patient outcomes. (Class I, Level C expert opinion).