Saline-irrigated, cooled-tip radiofrequency ablation is an effective technique to perform the maze procedure

Dual-modality fibre optic probe for simultaneous ablation and ultrasound imaging

All-optical ultrasound (OpUS) is an emerging high resolution imaging paradigm utilising optical fibres. This allows both therapeutic and imaging modalities to be integrated into devices with dimensions small enough for minimally invasive surgical applications. Here we report a dual-modality fibre optic probe that synchronously performs laser ablation and real-time all-optical ultrasound imaging for ablation monitoring. The device comprises three optical fibres: one each for transmission and reception of ultrasound, and one for the delivery of laser light for ablation. The total device diameter is < 1 mm. Ablation monitoring was carried out on porcine liver and heart tissue ex vivo with ablation depth tracked using all-optical M-mode ultrasound imaging and lesion boundary identification using a segmentation algorithm. Ablation depths up to 2.1 mm were visualised with a good correspondence between the ultrasound depth measurements and visual inspection of the lesions using stereomicroscopy. This work demonstrates the potential for OpUS probes to guide minimally invasive ablation procedures in real time.

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Atrial fibrillation surgical radiofrequency ablation (AFSA) during mitral valve surgery (MVS) has almost completely superseded the Cox-Maze procedure for the treatment of atrial fibrillation.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

Bi-atrial or left atrial ablation of atrial fibrillation during concomitant cardiac surgery: A Bayesian network meta-analysis of randomized controlled trials

OBJECTIVE

Surgical ablation of atrial fibrillation (AF) has become a routine procedure during concomitant cardiac surgery, however, the extension of lesion sets remain controversial. We sought to compare the relative benefit and risk of different lesion sets through a Bayesian network meta-analysis (NMA).

METHODS

Pubmed, Embase, and Cochrane Trials databases were searched for randomized controlled trials (RCTs) comparing the rhythm outcome of AF patients undergoing pulmonary vein isolation (PVI), left atrial Maze (LAM), bi-atrial Maze (BAM), or no ablation during concomitant cardiac surgery. An NMA was conducted to explore the difference of over 1 year AF freedom as well as risks for early mortality and permanent pacemaker implantation (PPMI).

RESULTS

A total of 2031 patients of 19 RCTs were included. PVI, LAM, and BAM (OR [95% Cr.I]: 5.02 [2.72, 10.02], 7.97 [4.93, 14.29], 8.29 [4.90, 14.86], p < .05) demonstrated higher freedom of AF compared with no ablation, however, no significant difference of rhythm outcome was found among the three ablation strategies based on the random-effects model. BAM was associated with an increase in early mortality when compared with no ablation (OR [95% Cr.I]: 4.08 [1.23, 17.30], p < .05), while none of the remaining comparisons reached statistical difference in terms of early mortality and PPMI.

CONCLUSION

Bi-atrial ablation is not superior to left atrial ablation strategies in reducing AF recurrence for un-selected surgical patients. BAM has a higher risk of early mortality than no ablation, but no difference was found between bi-atrial and left atrial ablation in regard to early mortality and PPMI based on the current evidence.

Surgical Treatment of Atrial Fibrillation: Cutting Through the Edges

Medical management of atrial fibrillation can be complex, challenging and requiring time to prove its effectiveness; furthermore, the response can be refractory and inconsistent if the underlying pathology is not permanently addressed. Surgical ablation has become a key intervention, and since its first intervention in 1987 (the Cox-maze procedure), the technique has evolved from a conventional open method to a minimally invasive technique whilst retaining excellent outcomes. Furthermore, recent advances in the use of a hybrid approach have been established as satisfactory approach in managing atrial fibrillation with satisfactory outcomes.

This literature review focuses on the evidence behind the surgical success in managing atrial fibrillation throughout the past, present and the future of these surgical interventions.

Amaze: a double-blind, multicentre randomised controlled trial to investigate the clinical effectiveness and cost-effectiveness of adding an ablation device-based maze procedure as an adjunct to routine cardiac surgery for patients with pre-existing atrial fibrillation

BACKGROUND

Atrial fibrillation (AF) can be treated using a maze procedure during planned cardiac surgery, but the effect on clinical patient outcomes, and the cost-effectiveness compared with surgery alone, are uncertain.

OBJECTIVES

To determine whether or not the maze procedure is safe, improves clinical and patient outcomes and is cost-effective for the NHS in patients with AF.

DESIGN

Multicentre, Phase III, pragmatic, double-blind, parallel-arm randomised controlled trial. Patients were randomised on a 1 : 1 basis using random permuted blocks, stratified for surgeon and planned procedure.

SETTING

Eleven acute NHS specialist cardiac surgical centres.

PARTICIPANTS

Patients aged ≥ 18 years, scheduled for elective or in-house urgent cardiac surgery, with a documented history (> 3 months) of AF.

INTERVENTIONS

Routine cardiac surgery with or without an adjunct maze procedure administered by an AF ablation device.

MAIN OUTCOME MEASURES

The primary outcomes were return to sinus rhythm (SR) at 12 months and quality-adjusted life-years (QALYs) over 2 years after randomisation. Secondary outcomes included return to SR at 2 years, overall and stroke-free survival, drug use, quality of life (QoL), cost-effectiveness and safety.

RESULTS

Between 25 February 2009 and 6 March 2014, 352 patients were randomised to the control (n = 176) or experimental (n = 176) arms. The odds ratio (OR) for return to SR at 12 months was 2.06 [95% confidence interval (CI) 1.20 to 3.54; p = 0.0091]. The mean difference (95% CI) in QALYs at 2 years between the two trial arms (maze/control) was -0.025 (95% CI 0.129 to 0.078; p = 0.6319). The OR for SR at 2 years was 3.24 (95% CI 1.76 to 5.96). The number of patients requiring anticoagulant drug use was significantly lower in the maze arm from 6 months after the procedure. There were no significant differences between the two arms in operative or overall survival, stroke-free survival, need for cardioversion or permanent pacemaker implants, New York Heart Association Functional Classification (for heart failure), EuroQol-5 Dimensions, three-level version score and Short Form questionnaire-36 items score at any time point. Sixty per cent of patients in each trial arm had a serious adverse event (p = 1.000); most events were mild, but 71 patients (42.5%) in the maze arm and 84 patients (45.5%) in the control arm had moderately severe events; 31 patients (18.6%) in the maze arm and 38 patients (20.5%) in the control arm had severe events. The mean additional cost of the maze procedure was £3533 (95% CI £1321 to £5746); the mean difference in QALYs was -0.022 (95% CI -0.1231 to 0.0791). The maze procedure was not cost-effective at £30,000 per QALY over 2 years in any analysis. In a small substudy, the active left atrial ejection fraction was smaller than that of the control patients (mean difference of -8.03, 95% CI -12.43 to -3.62), but within the predefined clinically equivalent range.

LIMITATIONS

Low recruitment, early release of trial summaries and intermittent resource-use collection may have introduced bias and imprecise estimates.

CONCLUSIONS

Ablation can be practised safely in routine NHS cardiac surgical settings and increases return to SR rates, but not survival or QoL up to 2 years after surgery. Lower anticoagulant drug use and recovery of left atrial function support anticoagulant drug withdrawal provided that good atrial function is confirmed.

FURTHER WORK

Continued follow-up and long-term clinical effectiveness and cost-effectiveness analysis. Comparison of ablation methods.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN82731440.

FUNDING

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 19. See the NIHR Journals Library website for further project information.

Biatrial maze procedure versus pulmonary vein isolation for atrial fibrillation during mitral valve surgery: New analytical approaches and end points

OBJECTIVE

To use novel statistical methods for analyzing the effect of lesion set on (long-standing) persistent atrial fibrillation (AF) in the Cardiothoracic Surgical Trials Network trial of surgical ablation during mitral valve surgery (MVS).

METHODS

Two hundred sixty such patients were randomized to MVS + surgical ablation or MVS alone. Ablation was randomized between pulmonary vein isolation and biatrial maze. During 12 months postsurgery, 228 patients (88%) submitted 7949 transtelephonic monitoring (TTM) recordings, analyzed for AF, atrial flutter (AFL), or atrial tachycardia (AT). As previously reported, more ablation than MVS-alone patients were free of AF or AF/AFL at 6 and 12 months (63% vs 29%; P < .001) by 72-hour Holter monitoring, without evident difference between lesion sets (for which the trial was underpowered).

RESULTS

Estimated freedom from AF/AFL/AT on any transmission trended higher after biatrial maze than pulmonary vein isolation (odds ratio, 2.31; 95% confidence interval, 0.95-5.65; P = .07) 3 to 12 months postsurgery; estimated AF/AFL/AT load (ie, proportion of TTM strips recording AF/AFL/AT) was similar (odds ratio, 0.90; 95% confidence interval, 0.57-1.43; P = .6). Within 12 months, estimated prevalence of AF/AFL/AT by TTM was 58% after MVS alone, and 36% versus 23% after pulmonary vein isolation versus biatrial maze (P < .02).

CONCLUSIONS

Statistical modeling using TTM recordings after MVS in patients with (long-standing) persistent AF suggests that a biatrial maze is associated with lower AF/AFL/AT prevalence, but not a lower load, compared with pulmonary vein isolation. The discrepancy between AF/AFL/AT prevalence assessed at 2 time points by Holter monitoring versus weekly TTM suggests the need for a confirmatory trial, reassessment of definitions for failure after ablation, and validation of statistical methods for assessing atrial rhythms longitudinally.

Left atrial concomitant surgical ablation for treatment of atrial fibrillation in cardiac surgery: A meta-analysis of randomized controlled trials

INTRODUCTION

Surgical ablation is a generally established treatment for patients with atrial fibrillation undergoing concomitant cardiac surgery. Left atrial (LA) lesion set for ablation is a simplified procedure suggested to reduce the surgery time and morbidity after procedure. The present meta-analysis aims to explore the outcomes of left atrial lesion set versus no ablative treatment in patients with AF undergoing cardiac surgery.

METHODS

A literature research was performed in six database from their inception to July 2017, identifying all relevant randomized controlled trials (RCTs) comparing left atrial lesion set versus no ablative treatment in AF patient undergoing cardiac surgery. Data were extracted and analyzed according to predefined clinical endpoints.

RESULTS

Eleven relevant RCTs were included for analysis in the present study. The prevalence of sinus rhythm in ablation group was significantly higher at discharge, 6-month and 1-year follow-up period. The morbidity including 30 day mortality, late all-cause mortality, reoperation for bleeding, permanent pacemaker implantation and neurological events were of no significant difference between two groups.

CONCLUSIONS

The result of our meta-analysis demonstrates that left atrial lesion set is an effective and safe surgical ablation strategy for AF patients undergoing concomitant cardiac surgery.

The Mid-Term Results of Patients who Underwent Radiofrequency Atrial Fibrillation Ablation Together with Mitral Valve Surgery

Objetive

Saline-irrigated radiofrequency ablation, which has been widely used for surgical treatment of atrial fibrillation in recent years, is 80-90% successful in achieving sinus rhythm. In our study, our surgical experience and mid-term results in patients who underwent mitral valve surgery and left atrial radiofrequency ablation were analyzed.

Methods

Forty patients (15 males, 25 females; mean age 52.05±9.9 years; range 32-74) underwent surgery for atrial fibrillation associated with mitral valvular disease. All patients manifested atrial fibrillation, which started at least six months before the surgical intervention. The majority of patients (36 patients, 90%) were in NYHA class III; 34 (85%) patients had rheumatic heart disease. In addition to mitral valve surgery and radiofrequency ablation, coronary artery bypass, DeVega tricuspid annuloplasty, left ventricular aneurysm repair, and left atrial thrombus excision were performed. Following discharge from the hospital, patients' follow-up was performed as outpatient clinic examinations and the average follow-up period of patients was 18±3 months.

Results

While the incidence of sinus rhythm was 85.3% on the first postoperative day, it was 80% during discharge and 71% in the 1^st year follow-up examination.

Conclusion

Radiofrequency ablation is an effective method when it is performed by appropriate surgical technique. Its rate for returning to sinus rhythm is as high as the rate of conventional surgical procedure.

Atrial fibrillation: review of current treatment strategies

Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia in modern clinical practice, with an estimated prevalence of 1.5-2%. The prevalence of AF is expected to double in the next decades, progressing with age and increasingly becoming a global medical challenge. The first-line treatment for AF is often medical treatment with either rate control or anti-arrhythmic agents for rhythm control, in addition to anti-coagulants such as warfarin for stroke prevention in patient at risk. Catheter ablation has emerged as an alternative for AF treatment, which involves myocardial tissue lesions to disrupt the underlying triggers and substrates for AF. Surgical approaches have also been developed for treatment of AF, particularly for patients requiring concomitant cardiac surgery or those refractory to medical and catheter ablation treatments. Since the introduction of the Cox-Maze III, this procedure has evolved into several modern variations, including the use of alternative energy sources (Cox-Maze IV) such as radiofrequency, cryo-energy and microwave, as well as minimally invasive thoracoscopic epicardial approaches. Another recently introduced technique is the hybrid ablation approach, where in a single setting both epicardial thoracoscopic ablation lesions and endocardial catheter ablation lesions are performed by the cardiothoracic surgeon and cardiologist. There remains controversy surrounding the optimal approach for AF ablation, energy sources, and lesion sets employed. The goal of this article is review the history, classifications, pathophysiology and current treatment options for AF.

Concomitant atrial fibrillation surgery for people undergoing cardiac surgery

BACKGROUND

People with atrial fibrillation (AF) often undergo cardiac surgery for other underlying reasons and are frequently offered concomitant AF surgery to reduce the frequency of short- and long-term AF and improve short- and long-term outcomes.

OBJECTIVES

To assess the effects of concomitant AF surgery among people with AF who are undergoing cardiac surgery on short-term and long-term (12 months or greater) health-related outcomes, health-related quality of life, and costs.

SEARCH METHODS

Starting from the year when the first "maze" AF surgery was reported (1987), we searched the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library (March 2016), MEDLINE Ovid (March 2016), Embase Ovid (March 2016), Web of Science (March 2016), the Database of Abstracts of Reviews of Effects (DARE, April 2015), and Health Technology Assessment Database (HTA, March 2016). We searched trial registers in April 2016. We used no language restrictions.

SELECTION CRITERIA

We included randomised controlled trials evaluating the effect of any concomitant AF surgery compared with no AF surgery among adults with preoperative AF, regardless of symptoms, who were undergoing cardiac surgery for another indication.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies and extracted data. We evaluated the risk of bias using the Cochrane 'Risk of bias' tool. We included outcome data on all-cause and cardiovascular-specific mortality, freedom from atrial fibrillation, flutter, or tachycardia off antiarrhythmic medications, as measured by patient electrocardiographic monitoring greater than three months after the procedure, procedural safety, 30-day rehospitalisation, need for post-discharge direct current cardioversion, health-related quality of life, and direct costs. We calculated risk ratios (RR) for dichotomous data with 95% confidence intervals (CI) using a fixed-effect model when heterogeneity was low (I² ≤ 50%) and random-effects model when heterogeneity was high (I² > 50%). We evaluated the quality of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework to create a 'Summary of findings' table.

MAIN RESULTS

We found 34 reports of 22 trials (1899 participants) with five additional ongoing studies and three studies awaiting classification. All included studies were assessed as having high risk of bias across at least one domain. The effect of concomitant AF surgery on all-cause mortality was uncertain when compared with no concomitant AF surgery (7.0% versus 6.6%, RR 1.14, 95% CI 0.81 to 1.59, I² = 0%, 20 trials, 1829 participants, low-quality evidence), but the intervention increased freedom from atrial fibrillation, atrial flutter, or atrial tachycardia off antiarrhythmic medications > three months (51.0% versus 24.1%, RR 2.04, 95% CI 1.63 to 2.55, I² = 0%, eight trials, 649 participants, moderate-quality evidence). The effect of concomitant AF surgery on 30-day mortality was uncertain (2.3% versus 3.1%, RR 1.25 95% CI 0.71 to 2.20, I² = 0%, 18 trials, 1566 participants, low-quality evidence), but the intervention increased the risk of permanent pacemaker implantation (6.0% versus 4.1%, RR 1.69, 95% CI 1.12 to 2.54, I² = 0%, 18 trials, 1726 participants, moderate-quality evidence). Investigator-defined adverse events, including but limited to, need for surgical re-exploration or mediastinitis, were not routinely reported but were not different between the two groups (other adverse events: 24.8% versus 23.6%, RR 1.07, 95% CI 0.85 to 1.34, I² = 45%, nine trials, 858 participants), but the quality of this evidence was very low.

AUTHORS' CONCLUSIONS

For patients with AF undergoing cardiac surgery, there is moderate-quality evidence that concomitant AF surgery approximately doubles the risk of freedom from atrial fibrillation, atrial flutter, or atrial tachycardia off anti-arrhythmic drugs while increasing the risk of permanent pacemaker implantation. The effects on mortality are uncertain. Future, high-quality and adequately powered trials will likely affect the confidence on the effect estimates of AF surgery on clinical outcomes.

Patients with minimal atrial fibrillation events should not undergo concomitant atrial ablation during open heart procedures

Several randomized controlled trials and meta-analyses have demonstrated improved freedom from atrial fibrillation with intraoperative atrial ablation. However, the increased bypass time and the risk for ablation-related complications should be weighed against the benefits in the decision-making. It is important to establish reasonable criteria to define candidates for surgical ablation. Furthermore, the efficacy and short- and long-term risks related to surgical ablation need to be considered. This article reviews the data on surgical ablation of atrial fibrillation as it pertains to these important issues. As shown the evidence does not support surgical ablation at the time of coronary artery bypass graft in some patients.

Surgical ablation of atrial fibrillation during mitral-valve surgery

BACKGROUND

Among patients undergoing mitral-valve surgery, 30 to 50% present with atrial fibrillation, which is associated with reduced survival and increased risk of stroke. Surgical ablation of atrial fibrillation has been widely adopted, but evidence regarding its safety and effectiveness is limited.

METHODS

We randomly assigned 260 patients with persistent or long-standing persistent atrial fibrillation who required mitral-valve surgery to undergo either surgical ablation (ablation group) or no ablation (control group) during the mitral-valve operation. Patients in the ablation group underwent further randomization to pulmonary-vein isolation or a biatrial maze procedure. All patients underwent closure of the left atrial appendage. The primary end point was freedom from atrial fibrillation at both 6 months and 12 months (as assessed by means of 3-day Holter monitoring).

RESULTS

More patients in the ablation group than in the control group were free from atrial fibrillation at both 6 and 12 months (63.2% vs. 29.4%, P<0.001). There was no significant difference in the rate of freedom from atrial fibrillation between patients who underwent pulmonary-vein isolation and those who underwent the biatrial maze procedure (61.0% and 66.0%, respectively; P=0.60). One-year mortality was 6.8% in the ablation group and 8.7% in the control group (hazard ratio with ablation, 0.76; 95% confidence interval, 0.32 to 1.84; P=0.55). Ablation was associated with more implantations of a permanent pacemaker than was no ablation (21.5 vs. 8.1 per 100 patient-years, P=0.01). There were no significant between-group differences in major cardiac or cerebrovascular adverse events, overall serious adverse events, or hospital readmissions.

CONCLUSIONS

The addition of atrial fibrillation ablation to mitral-valve surgery significantly increased the rate of freedom from atrial fibrillation at 1 year among patients with persistent or long-standing persistent atrial fibrillation, but the risk of implantation of a permanent pacemaker was also increased. (Funded by the National Institutes of Health and the Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT00903370.).

Freedom from atrial fibrillation after cox maze III ablation during follow-up

Background:

Nearly 60% of patients undergoing mitral valve (MV) operations are affected by atrial fibrillation (AF). Cox Maze III ablation is one of the effective ways for restoring sinus rhythm for patients undergoing open heart surgery. The aim of present study was to evaluate efficacy of Maze III ablation procedure for restoring sinus rhythm among patients who had underwent open heart surgery.

Materials and Methods:

During present descriptive-analytic prospective study 114 patients with chronic AF had undergone open heart surgery for their valvular or coronary artery diseases in Educational-Medical centres of Tabriz University of Medical Sciences (Tabriz, Iran) 2006-2012, were included in the study. For all patients Maze III ablation was done. Patients were evaluated by 12 lead electrocardiography (ECG) and 24 hours ambulatory ECG monitoring after 3-6 years (mean 4.8) of follow-up.

Result:

Patients' rhythm before Cox Maze III surgery was chronic AF in all patients. All patients were discharged from operating room with sinus rhythm. During intensive care unit (ICU) hospitalization, rhythm of 34 patients changed to AF and 80 patients had sinus rhythm. Sixteen patients had undergone electrical cardioversion for restoring sinus rhythm which was successful in 12 patients. Ninety-two patients had sinus rhythm when discharged from the hospital. After termination of follow-up, freedom from atrial fibrillation was 51%. Patients with AF during follow-up on surface ECG didn't have episodes of sinus rhythm in their ambulatory monitoring. One patient implanted cardiac pacemaker due to persistent sinus bradycardia.

Conclusion:

Based on the results of this study, Cox Maze III ablation procedure is an effective and safe way for restoring sinus rhythm among patients who are candidate for open heart surgery, while no significant complication was seen among patients.

Surgical ablation of atrial fibrillation

Surgical ablation of atrial fibrillation (AF) is currently performed in many major hospitals throughout the world. This paper reviews the development of surgical procedures for AF ablation. It is hoped that the paper can provide a foundation for those involved with ablation of AF to improve patient care. AF is triggered by a rapidly firing focus and could be treated with a localized ablation procedure. A large body of literature has confirmed the safety and efficacy of surgical ablation of AF. New ablation technologies have simplified the surgical treatment of AF and expanded the indications. Generally, more extensive lesion sets have had better long-term outcomes. Despite the tremendous progress that has been made in the development of surgical ablation of AF, many questions remain unanswered. It is anticipated that well designed clinical trials will continue to provide solid evidence to help formulate practice guidelines in the future.

Ablation technology for the surgical treatment of atrial fibrillation

The Cox maze procedure for the surgical treatment of atrial fibrillation has been simplified from its original cut-and-sew technique. Various energy sources now exist which create linear lines of ablation that can be used to replace the original incisions, greatly facilitating the surgical approach. This review article describes the anatomy of the atria that must be considered in choosing a successful energy source. Furthermore the device characteristics, safety profile, mechanism of tissue injury, and ability to create transmural lesions of the various energy sources that have been used in the Cox maze procedure, along with the strengths and weaknesses of each device is discussed.

Outcome of concomitantCox-maze III procedure using an argon-based cryosurgical system: a single-center experience with 250 patients

BACKGROUND

The Cox-Maze procedure (CM) for atrial fibrillation (AF) is associated with a high rate of sinus restoration. This study assessed the safety and efficacy of concomitant CM using an argon-based cryosurgical platform only.

METHODS

Data were collected prospectively for 250 consecutive patients undergoing concomitant cryosurgical CM. We examined baseline characteristics, perioperative and postoperative outcomes, health-related quality of life (Medical Outcomes Trust SF-12 Health Survey and AF Symptom Checklist) and Kaplan-Meier survival analysis.

RESULTS

Mean age was 64.3 ± 12.1 years, AF duration was 35.7 ± 54.2 months, left atrial size was 5.2 cm (range, 3.1 to 11.0 cm; 16.8% > 6 cm), 86% had nonparoxysmal AF, with history of cardioversion in 32% and catheter ablation in 8%. Concomitant procedures were mitral valve operation in 69.6%, coronary artery bypass graft in 29.2%, aortic valve replacement in 22.0%, with 46% multiple concomitant procedures and 16% with a previous cardiac operation. Perioperative outcomes were 5 deaths (2%), 3 strokes (1%), 1 transient ischemic attack (<1%), and 4 pacemakers for sinus node dysfunction (2%). There were no late thromboembolic events (mean follow-up, 28.2 ± 23.7 months), and 11% were taking warfarin for atrial arrhythmia at 1 year. Significant improvement in health-related quality of life (p < 0.001) was noted. At 24 months, 92.4% of patients were in sinus rhythm; with 82.8% in sinus rhythm off antiarrhythmic drugs. Two-year cumulative survival was 91%.

CONCLUSIONS

The cryosurgical CM procedure can be performed safely and effectively as defined by the low number of postoperative morbidities, high return to sinus rhythm off antiarrhythmic drugs, and low rate of thromboembolic events, with most patients off anticoagulation by 2 years.

Microwave Ablation in Mitral Valve Surgery for Atrial Fibrillation (MAMA)

Objective: Microwave ablation in conjunction with open heart surgery is effective in restoring sinus rhythm (SR) in patients with atrial fibrillation (AF). In patients assigned for isolated mitral valve surgery no prospective randomized trial has reported its efficacy. Methods: 70 patients with longlasting AF where included from 5 different centres. They were randomly assigned to mitral valve surgery and atrial microwave ablation or mitral valve surgery alone. Results: Out of 70 randomized, 66 and 64 patients were available for evaluation at 6 and 12 months. At 12 months SR was restored and preserved in 71.0 % in the ablation group vs 36.4 % in the control group (P=0.006), corresponding figures at 6 months was 62.5 % vs 26.5 % (P=0.003). The 30-day mortality rate was 1.4 %, with one death in the ablation group vs zero deaths in the control group. At 12 months the mortality rate was 7,1 % (Ablation n=3 vs Control n=2). No significant differences existed between the groups with regard to the overall rate of serious adverse events (SAE) during the perioperative period or at the end of the study. 16 % of patients randomized to ablation were on antiarrhytmic drugs compared to 6 % in the control group after 1 year (p=0.22). Conclusion: Microwave ablation of left and right atrium in conjunction with mitral valve surgery is safe and effectively restores sinus rhythm in patients with longlasting AF as compared to mitral valve surgery alone.

2012 HRS/EHRA/ECAS expert consensus statement on catheter and surgical ablation of atrial fibrillation: recommendations for patient selection, procedural techniques, patient management and follow-up, definitions, endpoints, and research trial design

This is a report of the Heart Rhythm Society (HRS) Task Force on Catheter and Surgical Ablation of Atrial Fibrillation, developed in partnership with the European Heart Rhythm Association (EHRA), a registered branch of the European Society of Cardiology and the European Cardiac Arrhythmia Society (ECAS), and in collaboration with the American College of Cardiology (ACC), American Heart Association (AHA), the Asia Pacific Heart Rhythm Society (APHRS), and the Society of Thoracic Surgeons (STS). This is endorsed by the governing bodies of the ACC Foundation, the AHA, the ECAS, the EHRA, the STS, the APHRS, and the HRS.

Maze Procedures for Atrial Fibrillation, From History to Practice

Atrial fibrillation may result in significant symptoms, (systemic) thrombo-embolism, as well as tachycardia-induced cardiomyopathy with cardiac failure, and consequently be associated with significant morbidity and mortality. Nowadays symptomatic atrial fibrillation can be treated with catheter-based ablation, surgical ablation or hybrid approaches. In this setting a fairly large number of surgical approaches and procedures are described and being practised. It should be clear that the Cox-maze procedure resulted from building up evidence and experience in different steps, while some of the present surgical approaches and techniques are being based only on technical feasibility with limited experience, rather than on a process of consequent methodology. Some of the issues still under debate are whether or not the maze procedure can be limited to the left atrium or even to isolation of the pulmonary veins or that bi-atrial procedures are indicated, whether or not cardiopulmonary bypass is to be applied and which route of exposure facilitates an optimal result. In addition, maze procedures are not procedures guide by electrophysiological mapping. At least in theory not in all patients all lesions of the maze procedures are necessary. A history and aspects of current practise in surgical treatment of atrial fibrillation is presented.

Designing comparative effectiveness trials of surgical ablation for atrial fibrillation: experience of the Cardiothoracic Surgical Trials Network

OBJECTIVE

Since the introduction of the cut-and-sew Cox maze procedure for atrial fibrillation, there has been substantial innovation in techniques for ablation. Use of alternative energy sources for ablation simplified the procedure and has resulted in dramatic increase in the number of patients with atrial fibrillation treated by surgical ablation. Despite its increasingly widespread adoption, there is lack of rigorous clinical evidence to establish this procedure as an effective clinical therapy.

METHODS

This article describes a comparative effectiveness randomized trial, supported by the Cardiothoracic Surgical Clinical Trials Network, of surgical ablation with left atrial appendage closure versus left atrial appendage closure alone in patients with persistent and long-standing persistent atrial fibrillation undergoing mitral valve surgery. Nested within this trial is a further randomized comparison of 2 different lesions sets: pulmonary vein isolation and the full maze lesion set.

RESULTS

This article addresses trial design challenges, including how best to characterize the target population, operationalize freedom from atrial fibrillation as a primary end point, account for the impact of antiarrhythmic drugs, and measure and analyze secondary end points, such as postoperative atrial fibrillation load.

CONCLUSIONS

This article concludes by discussing how insights that emerge from this trial may affect surgical practice and guide future research in this area.

Surgical Maze procedure as a treatment for atrial fibrillation: a meta-analysis of randomized controlled trials

Surgical or modified Maze procedures have been promoted to treat atrial fibrillation (AF); however, few randomized controlled clinical trials (RCTs) examine their outcomes. The purpose of this meta-analysis is to compare the efficacy of surgical Maze procedures performed concomitantly with referral cardiac surgery versus pharmacologic therapy for the treatment of AF. We searched MEDLINE, Cochrane database, FDA web-portal, and clinicaltrials.gov for all RCTs comparing surgical Maze procedures with medical therapy for sinus rhythm maintenance. Primary outcomes were either freedom from AF within 12 months postprocedure off antiarrhythmic drug (AAD), or freedom from AF while taking an AAD. Secondary outcomes included operative mortality, all-cause mortality, hospital length of stay, and postoperative complications. Both fixed- and random-effects models were used for a meta-analysis of 9 randomized controlled trials (n = 472, of which 249 underwent a Maze procedure and 213 underwent referral surgery alone). The surgical Maze procedure significantly increased the odds of freedom from AF within 12 months compared with cardiac surgery alone (OR 5.22, 95% CI 1.71-15.88). There was significant heterogeneity among the trials for freedom from AF (chi-square = 15.98 for 4 degrees of freedom, P= 0.003). Among the two studies that fully reported AAD use, there was no evidence of improved survival free from AF and AAD therapy (OR 1.78, 95% CI 0.73-4.34). Among patients with valvular AF, surgical Maze procedures are associated with a decrease in AF one year postprocedure without significant increase in mean length of hospital stay, perioperative complications, operative, or all-cause mortality. Large RCTs defining rates of freedom from AF without AADs postprocedure, are still needed to evaluate outcomes and determine the appropriate role for surgical Maze procedures in the management of AF.

Surgical Ablation for Atrial Fibrillation in Cardiac Surgery a Consensus Statement of the International Society of Minimally Invasive Cardiothoracic Surgery (ISMICS) 2009

Objective

This purpose of this consensus conference was to determine whether surgical atrial fibrillation (AF) ablation during cardiac surgery improves clinical and resource outcomes compared with cardiac surgery alone in adults undergoing cardiac surgery for valve or coronary artery bypass grafting.

Methods

Before the consensus conference, the consensus panel reviewed the best available evidence, whereby systematic reviews, randomized trials, and nonrandomized trials were considered in descending order of validity and importance. Evidence-based statements were created, and consensus processes were used to determine the ensuing recommendations. The American Heart Association/American College of Cardiology system was used to label the level of evidence and class of recommendation.

Results

The consensus panel agreed on the following statements in patients with AF undergoing cardiac surgery concomitant surgical ablation: 1. Improves the achievement of sinus rhythm at discharge and 1 year (level A); this effect is sustained up to 5 years (level B). Does not reduce the use of antiarrhythmic drugs at 12 months after surgery (level A; 36.0% vs. 45.4%), although trials were not designed to answer this question. 2. Does not increase the requirement for permanent pacemaker implantation (4.4% vs. 4.8%; level A). 3. Does not increase the risk of perioperative mortality (level A), stroke (level A), myocardial infarction (level B), cardiac tamponade (level A), reoperative bleeding (level A), esophageal injury (level B), low cardiac output (level A), intraaortic balloon (level B), congestive heart failure (level B), ejection fraction (EF; level B), pleural effusion (level A), pneumonia (level A), renal dysfunction (level B), and mediastinitis (level A). The incidence of esophageal injury remains to be low (level B). 4. Does not reduce mortality at 1 year (level A). There is a possible reduction in mortality beyond 1 year (level B), but no difference in stroke (level A), myocardial infarction (level A), and heart failure (level B). EF is increased (+4.1% more than control; level A). 5. Has been shown to improve exercise tolerance at 1 year (level A), but no impact on quality of life at 3 months and 1 year (level A); however, the methodology used and the number of trials studying these outcomes are insufficient. 6. Increases cardiopulmonary bypass and cross-clamp times (level A), with no difference in intensive care unit and hospital length of stay (level A). Overall costs were not reported.

Conclusions

Given these evidence-based statements, the consensus panel stated that, in patients with persistent and permanent AF undergoing cardiac surgery, concomitant surgical ablation is recommended to increase incidence of sinus rhythm at short- and long-term follow-up (class 1, level A); to reduce the risk of stroke and thromboembolic events (class 2a, level B); to improve EF (class 2a, level A); and to exercise tolerance (class 2a, level A) and long-term survival (class 2a, level B).

Surgical Ablation for Atrial Fibrillation in Cardiac Surgery a Meta-Analysis and Systematic Review

Objectives

This meta-analysis sought to determine whether surgical ablation improves clinical outcomes and resource utilization compared with no ablation in adult patients with persistent and permanent atrial fibrillation (AF) undergoing cardiac surgery.

Methods

A comprehensive search was undertaken to identify all randomized (RCT) and nonrandomized (non-RCT) controlled trials of surgical ablation versus no ablation in patients with AF undergoing cardiac surgery up to April 2009. The primary outcome was sinus rhythm. Secondary outcomes included survival and any other reported clinically relevant outcome or indicator of resource utilization. Odds ratios (OR) and weighted mean differences (WMD) and their 95% confidence intervals (95% CI) were analyzed as appropriate using the random effects model. Heterogeneity was measured using the I2 statistic. Meta-regression was performed to explore the relationship between the benefit from surgical AF and duration of follow-up.

Results

Thirty-three studies met the inclusion criteria (10 RCTs and 23 non-RCTs) for a total of 4647 patients. The number of patients in sinus rhythm was significantly improved at discharge in the surgical AF ablation group versus (68.6%) the surgery alone group (23.0%) in RCTs (OR 10.1, 95% CI 4.5–22.5) and non-RCTs (OR 7.15, 95% CI 3.42–14.95). This effect on sinus rhythm (74.6% vs. 18.4%) remained at follow-up of 1 to 5 years (OR 6.7, 95% CI 2.8–15.7 for RCT, and OR 15.5, 95% CI 6.6–36.7 for non-RCT). The risk of all-cause mortality at 30 days was not different between the groups in RCT (OR 1.20, 95% CI 0.52–3.16) or non-RCT studies (OR 0.99, 95% CI 0.52–1.87). In studies reporting all-cause mortality at 1 year or more (up to 5 years), mortality did not differ in RCT studies (OR 1.21, 95% CI 0.59–2.51) but was significantly reduced in non-RCT studies (OR 0.54, 95% CI 0.31–0.96). Stroke incidence was not reduced significantly; however, in meta-regression, the risk of stroke decreased significantly with longer follow-up. Other clinical outcomes were similar between groups. Operation time was significantly increased with surgical AF ablation; however, overall impact on length of stay was variable.

Conclusions

In patients with persistent or permanent AF who present for cardiac surgery, the addition of surgical AF ablation led to a significantly higher rate of sinus rhythm in RCT and non-RCT studies compared with cardiac surgery alone, and this effect remains robust over the longer term (1–5 years). Although non-RCT studies suggest the possibility of reduced risk of stroke and death, this remains to be proven in prospective RCTs with adequate power and follow-up.

Efficacy of a novel bipolar radiofrequency ablation device on the beating heart for atrial fibrillation ablation: a long-term porcine study

OBJECTIVE

Over recent years, a variety of energy sources have been used to replace the traditional incisions of the Cox maze procedure for the surgical treatment of atrial fibrillation. This study evaluated the safety and efficacy of a new bipolar radiofrequency ablation device for atrial ablation in a long-term porcine model.

METHODS

Six pigs underwent a Cox maze IV procedure on a beating heart off cardiopulmonary bypass using the AtriCure Isolator II bipolar ablation device (AtriCure, Inc, Cincinnati, Ohio). In addition, 6 pigs underwent median sternotomy and pericardiotomy alone to serve as a control group. All animals were allowed to survive for 30 days. Each pig underwent induction of atrial fibrillation and was then humanely killed to remove the heart en bloc for histologic assessment. Magnetic resonance imaging scans were also obtained preoperatively and postoperatively to assess atrial and ventricular function, pulmonary vein anatomy, valve function, and coronary artery patency.

RESULTS

All animals survived the operation. Electrical isolation of the left atrial appendage and the pulmonary veins was documented by pacing acutely and at 30 days in all animals. No animal that underwent the Cox maze IV procedure was able to be induced into atrial fibrillation at 30 days postoperatively, compared with all the sham animals. All 257 ablations examined were discrete, linear, and transmural, with a mean lesion width of 2.2 +/- 1.1 mm and a mean lesion depth of 5.3 +/- 3.0 mm.

CONCLUSIONS

The AtriCure Isolator II device was able to create reliable long-term transmural lesions of the modified Cox maze procedure on a beating heart without cardiopulmonary bypass 100% of the time. There were no discernible effects on ventricular or valvular function.

Current Concepts in Ablation of Atrial Fibrillation

Atrial fibrillation (AF) is the most common arrhythmia in clinical practice. It occurs particularly frequently in cardiac surgical patients and is associated with significant excess mortality and morbidity. Pharmacological management of AF is relatively ineffective and associated with significant side effects and complications. Clinicians have therefore pursued more definitive treatment options, both catheter based and surgical, to treat patients with AF. Surgical techniques designed to cure AF have developed in parallel with an improved understanding of the pathophysiological processes underlying this condition. This review describes the rationale behind current surgical approaches to AF and summarizes the results achieved with current techniques.

[Cost-benefit analysis of concomitant atrial fibrillation management in Spain]

OBJECTIVES

Atrial fibrillation (AF) is the most common arrhythmia in clinical practice; this disorder is a risk factor for stroke and is associated with substantial morbidity and mortality. Our objective was to develop a cost-utility analysis of the different treatment alternatives in patients aged 40 years old or more with concomitant AF with valve disease in Spain, from the National Health System perspective.

METHODS

An economic evaluation through a Markov model with four health states (sinus rhythm, AF, dependent stroke, death) was developed to simulate the evolution of a cohort of 1,000 patients receiving each treatment alternative in addition to mitral valve surgery (drug therapy, surgical ablation and catheter ablation). The time horizon was 5 years, with a cycle length of 3 months. Data on costs and effects were obtained from the published literature and expert opinion and were discounted at 3.5%. A sensitivity analysis was developed to determine the robustness of the results.

RESULTS

The quality-adjusted life years (QALY) gained were 3.29, 3.89, and 3.83, respectively, for the alternatives of no ablation, surgical ablation and catheter ablation. The costs per patient were 5,770euro, 10,034euro and 11,289euro, respectively. The surgical ablation cost/QALY rate compared with no ablation was 7,145euro. Surgical ablation was dominant versus catheter ablation. The probabilistic sensitivity analysis showed that the results were robust.

CONCLUSIONS

Surgical ablation is a cost-effective treatment option in patients with concomitant AF, with a cost-effectiveness ratio under the efficiency threshold commonly accepted in Spain.

The surgical treatment of atrial fibrillation

Atrial fibrillation is a complex disease affecting a significant portion of the general population. Although medical therapy is the mainstay of treatment, intervention plays an important role in selected patients. The Cox-Maze procedure is the gold standard for the surgical treatment of atrial fibrillation and has more than 90% success in eliminating atrial fibrillation. Ablation technologies have played a key role in simplifying this technically demanding procedure and making it available to more patients. A myriad of new lesion sets and approaches were introduced over the last decade which has made the operative treatment of atrial fibrillation less invasive and more confusing.

Concomitant ablation of atrial fibrillation in octogenarians: an observational study

BACKGROUND

Cardiac surgery is increasingly required in octogenarians. These patients frequently present atrial fibrillation (AF), a significant factor for stroke and premature death. During the last decade, AF ablation has become an effective procedure in cardiac surgery. Because the results of concomitant AF ablation in octogenarians undergoing cardiac surgery are still not clear, we evaluated the outcome in these patients.

METHODS

Among 200 patients undergoing concomitant AF ablation (87% persistent AF), 28 patients were >/= 80 years (82 +/- 2.4 years). The outcome was analysed by prospective follow up after 3, 6, 12 months and annually thereafter. Freedom from AF was calculated according to the Kaplan-Meier method.

RESULTS

Octogenarians were similar to controls regarding AF duration (48 +/- 63.2 versus 63 +/- 86.3 months, n.s.) and left atrial diameter (49 +/- 6.1 versus 49 +/- 8.8 mm, n.s.), but differed in EuroSCORE (17.3 +/- 10.93 versus 7.4 +/- 7.31%, p < 0.001), prevalence of paroxysmal AF (25.0 versus 11.0%, p = 0.042) and aortic valve disease (67.8 versus 28.5%, p < 0.001). ICU stay (8 +/- 16.9 versus 4 +/- 7.2 days, p = 0.027), hospital stay (20 +/- 23.9 versus 14 +/- 30.8 days, p < 0.05), and 30-d-mortality (14.3 versus 4.6%, p = 0.046) were increased. After 12 +/- 6.1 months of follow-up (95% complete), 14 octogenarians (82%) and 101 controls (68%, n.s.) were in sinus rhythm; 59% without antiarrhythmic drugs in either group (n.s.). Sinus rhythm restoration was associated with improved NYHA functional class and renormalization of left atrial size. Cumulative freedom from AF demonstrated no difference between groups. Late mortality was higher in octogenarians (16.7 versus 6.1%, p = 0.065).

CONCLUSION

Sinus rhythm restoration rate and functional improvement are satisfactory in octogenarians undergoing concomitant AF ablation. Hence, despite an increased perioperative risk, this procedure should be considered even in advanced age.

A health economic evaluation of concomitant surgical ablation for atrial fibrillation

OBJECTIVE

Current drug treatment for atrial fibrillation is suboptimal and percutaneous catheter-based ablation techniques may be associated with complications. The aim of this study is to assess the cost-effectiveness of (1) high-intensity focused ultrasound (HIFU)-assisted surgical ablation, (2) the classic 'cut and sew' maze procedure and (3) percutaneous ablation, all concomitant to cardiac surgery (e.g. CABG, valve repair) in comparison with non-interventional (drug) treatment.

METHODS

A Markov model was developed to predict the cost-effectiveness of the interventional approaches. The model consisted of four disease states (sinus rhythm without complications, atrial fibrillation without complications, stroke and death), allowing for 3-monthly transitions between these states and using direct UK costs from the National Health Service perspective. Clinical input data are obtained from literature and cost input data from National Health Service sources and literature. Five-year total and incremental costs are calculated. Incremental effects are expressed in quality-adjusted-life-years-gained (QALYG).

RESULTS

All interventional treatments show good incremental cost-effectiveness ratios in all atrial fibrillation types, compared to drug treatment. For classic maze the incremental cost-effectiveness ratio compared to non-interventional atrial fibrillation treatment varies from 1343 to 3471 GBP/QALYG, for HIFU-assisted surgical ablation from 4005 to 7448 GBP/QALYG and for percutaneous ablation from 7041 to 17,372 GBP/QALYG depending on the atrial fibrillation type. Sensitivity analyses showed the robustness of the data.

CONCLUSIONS

Performing a classic maze procedure or HIFU-assisted surgical ablation concomitant to a scheduled CABG or valve procedure is highly cost-effective. Performing a percutaneous ablation in a subsequent procedure is also cost-effective, but to a lower extent. Both the maze procedure and the HIFU-assisted surgical ablation are cheaper and more effective than percutaneous ablation in a subsequent procedure.

Surgical Ablation of Atrial Fibrillation in Patients With Congestive Heart Failure

BACKGROUND

Congestive heart failure (CHF) and atrial fibrillation (AF), both of which cause morbidity and mortality, are mutually promoting diseases. We aimed to evaluate surgical AF ablation in CHF.

METHODS AND RESULTS

Among 212 patients (age 69 +/- 8.8 years, 87% with persistent AF) undergoing concomitant left atrial (LA) ablation, 79 (37.3%) presented CHF (n = 62 with a left ventricular ejection fraction [LVEF] 0.31-0.45, n = 17 with an LVEF < or = 0.30). Patients with CHF were similar to controls regarding AF duration (61 +/- 65.1 months vs. 54 +/- 67.2 months, not significant [NS]), LA diameter (49 +/- 7.5 mm vs. 50 +/- 9.2 mm, NS), and heart rate (78 +/- 18.4 min(-1) vs. 81 +/- 21.3 min(-1), NS), but they required more circulatory support (17.7% vs. 1.5%, P < .001) and a longer intensive care unit stay (6 +/- 9.5 days vs. 4 +/- 10.5 days, P = .032). At follow-up after 13 +/- 7.3 months, 42 patients (66%) with CHF and 81 controls (74%, NS) were in sinus rhythm (SR) (55% and 64% without antiarrhythmic drugs, respectively, NS). Univariate and logistic regression analysis revealed that AF duration and LA diameter predicted rhythm outcome but not CHF. In patients with an LVEF of 0.30 or less, SR conversion significantly improved LVEF, New York Heart Association class, and Minnesota Living with Heart Failure score. Kaplan-Meier estimates suggested superior survival of patients with stable SR (100% vs. 73%, log-rank P < .05).

CONCLUSIONS

If patients presenting with CHF and AF require cardiac surgery, concomitant AF ablation should be considered, especially if left ventricular function is severely impaired.

Concomitant Ablation of Atrial Fibrillation: Are Results Associated With Surgeon's Experience?

BACKGROUND AND AIM OF THE STUDY

Atrial fibrillation (AF) ablation has become an effective concomitant procedure, which is increasingly used. We questioned whether results are related to surgeon's experience.

METHODS

Patients (n = 141) with persistent AF (pAF) underwent concomitant left atrial (LA) endocardial ablation, performed by six surgeons. Follow-up (FU) was after 3, 6, and 12 months (mean 8 +/- 4.1 months). FU was 97% complete. Results were analyzed according to surgeon's volume: >20 (group A, n = 85) and <or=20 (group B, n = 56) ablations per year.

RESULTS

Baseline data of groups A and B were similar regarding age (70 +/- 9.0 vs. 70 +/- 8.1 years, n.s.), NYHA class (3.0 +/- 0.84 vs. 2.9 +/- 0.95, n.s.), AF duration (58 +/- 83.4 vs. 63 +/- 69.4 months, n.s.), LA diameter (50 +/- 8.5 vs. 48 +/- 7.3 mm, n.s.), and LVEF (50 +/- 12.0 vs. 50 +/- 13.0%, n.s.). Overall mortality (30 days) was 7.1% (six and four in groups A and B, n.s.). Ablation caused no injury or death. At FU sinus rhythm (SR) conversion rate was 68.1% in each group. Atrial contraction was demonstrated in 86.0 and 90.3% of SR patients in groups A and B (n.s.). NYHA functional class improved and was similar in both groups (A: 2.1 +/- 0.56, B: 2.1 +/- 0.48, n.s.). Compared to non-SR, SR was associated with better NYHA class (A: 2.0 +/- 0.57 vs. 2.3 +/- 0.46, p < 0.05; B: 2.0 +/- 0.44 vs. 2.3 +/- 0.47, p < 0.05) and smaller LA diameter (A: 42 +/- 5.5 vs. 46 +/- 8.4 mm, p < 0.05; B: 40 +/- 5.5 vs. 45 +/- 5.8 mm, p < 0.05).

CONCLUSIONS

We found no association between surgeon's experience and results of AF ablation, neither in SR conversion rate nor in morbidity and mortality.

Surgical ablation of atrial fibrillation: the Columbia Presbyterian experience

BACKGROUND

The Maze III procedure is an effective surgical treatment for atrial fibrillation (AF). However, it is not widely applied due to its complexity, increased operative times, and the risk of bleeding. Various energy sources have been introduced to simplify the traditional "cut and sew" approach.

METHODS

This study involves patients undergoing surgical atrial fibrillation ablation (SAFA) at a single institution from 1999 to 2005. Type of concomitant procedures, preoperative clinical characteristics, and chronicity of AF were evaluated in overall patient population. Parameters including surgical approach, lesion pattern, and energy source used were collected intraoperatively. Clinical outcomes examined were postoperative rhythm success, stroke, early mortality, and long-term survival.

RESULTS

Three hundred thirty-nine patients were identified. Three hundred twenty-eight (96.8%) patients had associated cardiac disease and underwent concomitant procedures; 75.8% of patients had persistent AF. Energy sources used were microwave (49.8%), radiofrequency (42.2%), and laser (8.0%). In 41.9% of cases a pulmonary vein encircling lesion was the only lesion created. Combination lesion sets were performed in the remaining cases. Rhythm success rates at 3, 6, 12, and 24 months were 74.1%, 68.2%, 74.5%, and 71.1%, respectively. Patients who underwent surgical removal of left atrial appendage by means of stapling or simple excision had no early postoperative stroke. Early mortality was 4.9%. Postoperative survival rates at 1, 3, and 5 years were 89.6%, 83.1%, and 78.0%.

CONCLUSIONS

Surgical ablation of atrial fibrillation is a safe and effective procedure in restoring sinus rhythm with excellent postoperative survival rates. Further advancements in the field will eventually result in minimally invasive procedures with higher success rates.