Hybrid Atrial Fibrillation Ablation

Narrative Review: Surgical and Hybrid Management of Atrial Fibrillation

Although significant strides have been made in non-pharmacologic management of atrial fibrillation (AF), these treatments remain a work in progress. While catheter ablation is often effective for management of paroxysmal AF, it is less successful in patients with persistent or longstanding persistent AF. This review was undertaken to clarify the risks, benefits, and alternatives to catheter ablation for non-pharmacologic AF management. In order to clarify the roles of surgical and hybrid ablation, this narrative review was undertaken by searching MEDLINE to identify peer-reviewed clinical trials, randomized controlled trials, meta-analyses, review articles, and other clinically relevant studies. The search was limited to English-language reports published between 1960 and 2023. Atrial fibrillation was searched using the terms surgical ablation, catheter ablation, hybrid ablation, stroke prevention, left atrial occlusion, and atrial excision. Google and Google Scholar, as well as bibliographies of identified articles, were also reviewed for additional references. The Cox-maze surgical approach is still the most efficacious non-pharmacological treatment for AF. Hybrid ablation, combining cardiac surgical and catheter ablation techniques, has become an attractive option for persistent or longstanding persistent AF.

Long-term clinical outcomes and cost-effectiveness of catheter vs thoracoscopic surgical ablation in long-standing persistent atrial fibrillation using continuous cardiac monitoring: CASA-AF randomized controlled trial

BACKGROUND

Long-term clinical outcomes of catheter ablation (CA) compared to thoracoscopic surgical ablation (SA) to treat patients with long-standing persistent atrial fibrillation (LSPAF) are not known.

OBJECTIVE

The purpose of this study was to compare the long-term (36-month) clinical efficacy, quality of life, and cost-effectiveness of SA and CA in LSPAF.

METHODS

Participants were followed up for 3 years using implantable loop recorders and questionnaires to assess the change in quality of life. Intention-to-treat analyses were used to report the findings.

RESULTS

Of the 115 patients with LSPAF treated, 104 (90.4%) completed 36-month follow-up [CA: n = 57 (95%); SA: n = 47 (85%)]. After a single procedure without antiarrhythmic drugs, 7 patients (12%) in the CA arm and 5 (11%) in the SA arm [hazard ratio 1.22; 95% confidence interval (CI) 0.81-1.83; P = .41] were free from atrial fibrillation/tachycardia (AF/AT) ≥30 seconds at 36 months. Thirty-three patients (58%) in the CA arm and 26 (55%) in the SA arm (hazard ratio 1.04; 95% CI 0.57-1.88; P = .91) had their AF/AT burden reduced by ≥75%. The overall impact on health-related quality of life was similar, with mean quality-adjusted life year estimates of 2.45 (95% CI 2.31-2.59) for CA and 2.32 (95% CI 2.13-2.52) for SA. Estimated costs were higher for SA (mean £24,682; 95% CI £21,746-£27,618) than for CA (mean £18,002; 95% CI £15,422-£20,581).

CONCLUSION

In symptomatic LSPAF, CA and SA were equally effective at achieving arrhythmia outcomes (freedom from AF/AT ≥30 seconds and ≥75% burden reduction) after a single procedure without antiarrhythmic drugs. However, SA is significantly more costly than CA.

Hybrid atrial fibrillation ablation: long-term outcomes from a single-centre 10-year experience

AIMS

Hybrid atrial fibrillation (AF) ablation is a promising approach in non-paroxysmal AF. The aim of this study is to assess the long-term outcomes of hybrid ablation in a large cohort of patients after both an initial and as a redo procedure.

METHODS AND RESULTS

All consecutive patients undergoing hybrid AF ablation at UZ Brussel from 2010 to 2020 were retrospectively evaluated. Hybrid AF ablation was performed in a one-step procedure: (i) thoracoscopic ablation followed by (ii) endocardial mapping and eventual ablation. All patients received PVI and posterior wall isolation. Additional lesions were performed based on clinical indication and physician judgement. Primary endpoint was freedom from atrial tachyarrhythmias (ATas). A total of 120 consecutive patients were included, 85 patients (70.8%) underwent hybrid AF ablation as first procedure (non-paroxysmal AF 100%), 20 patients (16.7%) as second procedure (non-paroxysmal AF 30%), and 15 patients (12.5%) as third procedure (non-paroxysmal AF 33.3%). After a mean follow-up of 62.3 months ± 20.3, a total of 63 patients (52.5%) experienced ATas recurrence. Complications occurred in 12.5% of patients. There was no difference in ATas between patients undergoing hybrid as first vs. redo procedure (P = 0.53). Left atrial volume index and recurrence during blanking period were independent predictors of ATas recurrence.

CONCLUSION

In a large cohort of patients undergoing hybrid AF ablation, the survival from ATas recurrence was 47.5% at ≈5 years follow-up. There was no difference in clinical outcomes between patients undergoing hybrid AF ablation as first procedure or as a redo.

Atrial fibrillation: Primary prevention, secondary prevention, and prevention of thromboembolic complications: Part 2

Atrial fibrillation (AF), the most common sustained cardiac arrhythmia, once thought to be benign as long as the ventricular rate was controlled, is associated with significant cardiac morbidity and mortality. Increasing life expectancy driven by improved health care and decreased fertility rates has, in most of the world, resulted in the population aged ≥65 years growing more rapidly than the overall population. As the population ages, projections suggest that the burden of AF may increase more than 60% by 2050. Although considerable progress has been made in the treatment and management of AF, primary prevention, secondary prevention, and prevention of thromboembolic complications remain a work in progress. This narrative review was facilitated by a search of MEDLINE to identify peer-reviewed clinical trials, randomized controlled trials, meta-analyses, and other clinically relevant studies. The search was limited to English-language reports published between 1950 and 2021. Atrial fibrillation was searched using the terms primary prevention, hyperthyroidism, Wolff-Parkinson-White syndrome, catheter ablation, surgical ablation, hybrid ablation, stroke prevention, anticoagulation, left atrial occlusion and atrial excision. Google and Google scholar as well as bibliographies of identified articles were reviewed for additional references. In these two manuscripts, we discuss the current strategies available to prevent AF, then compare non-invasive and invasive treatment strategies to diminish AF recurrence. In addition, we examine the pharmacological, percutaneous device and surgical approaches to prevent stroke as well as other types of thromboembolic events.

Hybrid Ablation of Atrial Fibrillation: A Contemporary Overview

Electrical isolation of pulmonary veins (PVI) is the cornerstone of invasive treatment of atrial fibrillation (AF). However, arrhythmia-free survival of a PVI only approach is suboptimal in patients with persistent and long-term persistent AF. Hybrid AF ablation has been developed with the aim of combining the advantages of a thoracoscopic surgical ablation (direct visualization of anatomical structures to be spared and the possibility to perform epicardial lesions) and endocardial ablation (possibility to check line block, confirm PVI, and possibility to perform cavotricuspid isthmus ablation). Patient selection is of utmost importance. In persistent and long-term persistent AF, hybrid AF ablation demonstrated promising results in terms of AF free survival. It has been associated with a relatively low complication rate if performed in centers with expertise in hybrid procedures and experience with both surgical and endocardial ablation. Different techniques have been described, with different approaches and lesion sets. The aim of this review is to provide a state-of-the-art overview of hybrid AF ablation.

Hybrid convergent ablation versus endocardial catheter ablation for atrial fibrillation: a systematic review and meta-analysis of randomised control trials and propensity matched studies

INTRODUCTION

Atrial fibrillation (AF) is the most common arrhythmia. Hybrid convergent ablation (HCA) is an emerging procedure for treating longstanding AF with promising results. HCA consists of a subxiphoid, surgical ablation followed by completion endocardial ablation. This meta-analysis of randomized control trials (RCT's) and propensity score-matched studies aims to examine the efficacy and safety of HCA compared to endocardial catheter ablation (ECA) alone on patients with AF.

METHODS

This review was written in accordance with preferred reporting items for systematic reviews and meta-analyses recommendations and guidance. The primary outcome for the analysis was freedom from AF (FFAF) at final follow up. Secondary outcomes were mortality and significant complications such as tamponade, sternotomy, esophageal injury, atrio-esophageal fistulae post procedurally.

RESULTS

Four studies where included, with a total of 233 patients undergoing HCA and 189 patients undergoing ECA only. Pooled analysis demonstrated that HCA cohorts had significantly higher rates of FFAF than ECA cohorts, with an OR of 2.78 (95% CI 1.82-4.24, P < 0.01, I2 = 0). Major post-operative complications were observed in significantly more patients in the HCA group, with an OR of 5.14 (95% CI 1.70-15.54, P < 0.01). There was only one death reported in the HCA cohorts, with no deaths in the ECA cohort.

CONCLUSION

HCA is associated with a significantly higher FFAF than ECA, however, it is associated with increased post-procedural complications. There was only one death in the HCA cohort. Large RCT's comparing the HCA and ECA techniques may further validate these results.

Hybrid convergent ablation versus endocardial catheter ablation for atrial fibrillation: A systematic review and meta-analysis

INTRODUCTION

Endocardial catheter ablation (ECA) for atrial fibrillation (AF) has limited efficacy. Hybrid convergent procedure (HCP) with both epicardial and endocardial ablation is a novel strategy for AF treatment. In this meta-analysis, we aimed to evaluate the efficacy and safety of HCP in AF ablation.

METHOD

We performed a comprehensive literature search for studies that evaluated the efficacy and safety of HCP compared with ECA for AF. The primary outcome was freedom of atrial arrhythmia (AA). The secondary outcome was the periprocedural complication rate. Pooled relative risk (RR) and corresponding 95% confidence intervals (CIs) were calculated using the random effects model.

RESULTS

A total of eight studies, including 797 AF patients (mean age: 60.7 ± 9.8 years, 366 patients with HCP vs. 431 patients with ECA alone), were included. HCP showed a higher rate of freedom of AA compared with ECA (RR: 1.48, 95% CI: 1.13-1.94, p = .004). However, HCP was associated with higher rates of periprocedural complications (RR: 3.64, 95% CI: 2.06-6.43; p = .00001). Moreover, the HCP had a longer procedure time and postprocedural hospital stay.

CONCLUSIONS

Although hybrid ablation was associated with a higher success rate, this should be judged for increased periprocedural adverse events and extended hospital stay. Prospective large-scale randomized trials are needed to validate these results.

The fate of patients after failed epicardial ablation of atrial fibrillation

Background

Much debate is still going on about the best ablation strategy—via endocardial or epicardial approach—in patients with atrial fibrillation (AF), and evidence gaps exist in current guidelines in this area. More specifically, there are no clear long-term outcome data after failed surgical AF ablation.

Methods

Since June 2008, 549 surgical AF ablation procedures through a right minithoracotomy were performed at our institution. From 2008 to 2011, a unipolar radiofrequency device was used (151 patients), whereas from 2011 to 2020 a bipolar radiofrequency device was used (398 patients). Patients were scheduled for surgery on the basis of the following criteria: recurrent episodes of paroxysmal or persistent lone AF refractory to maximally tolerated antiarrhythmic drug dosing and at least one failed cardioversion attempt. Besides the recommended follow-up by the local cardiologist, starting from 2021, surviving patients were asked to undergo assessment of left ventricular function and to complete a questionnaire addressing quality of life and predisposing factors for recurrent AF.

Results

At a mean follow-up of 77 months, the rate of AF recurrence was 20.7% (n = 114). On multivariate analysis, impaired left ventricular ejection fraction (58 patients, 51%, p = 0.002), worsening of European Heart Rhythm Association (EHRA) symptom class (37 patients, 32%, p = 0.003) and cognitive decline or depression (23 patients, 20%, p = 0.023) during follow-up were found to be significantly associated with AF recurrence.

Conclusions

Surgical AF ablation through a right minithoracotomy is safe, but a better outcome could be achieved using a hybrid approach. Patients after initial failed surgical AF ablation show worsening of cardiac function, clinical status and quality of life at follow-up compared to patients with successful AF ablation.

Stepwise endo-/epicardial catheter ablation for atrial fibrillation: The Mediterranea approach

BACKGROUND

Outcomes of catheter ablation (CA) among patients with nonparoxysmal atrial fibrillation (AF) are largely disappointing.

OBJECTIVE

We sought to evaluate the feasibility, effectiveness, and safety of a single-stage stepwise endo-/epicardial approach in patients with persistent/longstanding-persistent AF.

METHODS

We enrolled 25 consecutive patients with symptomatic persistent (n = 4) or longstanding-persistent (n = 21) AF and at least one prior endocardial procedure, who underwent CA using an endo-/epicardial approach. Our anatomical stepwise protocol included multiple endocardial as well as epicardial (Bachmann's bundle [BB] and ligament of Marshall ablations) components, and entailed ablation of atrial tachycardias emerging during the procedure. The primary outcome was freedom from any AF/atrial tachycardia episode after a 3-month blanking period. The secondary outcome was patients' symptom status during follow-up.

RESULTS

The stepwise endo-/epicardial approach allowed sinus rhythm restoration in 72% of patients, either directly (n = 6, 24%) or after AF organization into atrial tachycardia (n = 12, 48%). BB's ablation was commonly implicated in arrhythmia termination. After a median follow-up of 266 days (interquartile range, 96 days), survival free from AF/atrial tachycardia was 88%. Antiarrhythmic drugs could be discontinued in 22 patients (88%). As compared to baseline, more patients were asymptomatic at 9-month follow-up (0% vs. 56%, p = .02). Five patients (20%) developed mild medical complications, whereas one subject (4%) had severe kidney injury requiring dialysis.

CONCLUSION

A single-stage endo-/epicardial CA resulted in favorable rhythm and symptom outcomes in a cohort of patients with symptomatic persistent/longstanding-persistent AF and one or more prior endocardial procedures. Epicardial ablation of BB was commonly implicated in procedural success.

A narrative review of hybrid ablation for persistent and longstanding persistent atrial fibrillation

Atrial fibrillation is the most common sustained arrhythmia and is characterized by rapid and irregular atrial activation with loss of atrial contraction. There has been a significant evolution of treatments over the past 30 years. Initially, cardiac surgeons developed approaches via sternotomy with superior efficacy, however early iterations of the procedure were associated with prolonged recovery time and frequent need for pacemaker placement. The current surgical approach to the maze procedure via sternotomy yields excellent efficacy and is a Class 1 recommendation for patients with atrial fibrillation undergoing a concomitant procedure. Several years following the initial development of the surgical maze procedure, cardiac electrophysiologists developed less invasive, however less efficacious catheter ablation options by percutaneous approach. Both the surgical and transcatheter approaches have their advantages and disadvantages with varying risks of complications and efficacy. Through the combination of expertise of cardiac surgeons paired with the electrophysiology team, a hybrid ablation procedure has been developed offering an increased efficacy with a less-invasive approach than the current gold standard treatment of Cox-maze IV procedure. This review will discuss the hybrid ablation procedure, review recent associated clinical trials, and discuss advantages and challenges associated with this multidisciplinary approach for management of patients with AF.

Simultaneous hybrid maze procedure for long-standing persistent atrial fibrillation with dilated atrium

Background

The efficacy of catheter-based or thoracoscopic ablation for treating long-standing persistent atrial fibrillation (AF) with a dilated atrium remains suboptimal. This study aimed to assess the feasibility and initial results of simultaneous hybrid ablation with a new biatrial lesion set in these patients.

Methods

Twenty-seven consecutive patients with long-standing persistent AF and dilated atrium underwent simultaneous hybrid ablation with a new biatrial lesion set consistent with the principle of the Cox maze procedure at our institution. Patients were followed up at 3, 6, and 12 months after the procedure and annually thereafter.

Results

After thoracoscopic epicardial ablation, endocardial mapping confirmed complete bilateral pulmonary vein isolation in 25 patients (96.2%). All patients were followed for a mean of 18.7 ± 8.9 months. Freedom from atrial tachyarrhythmia at 1 year after the single hybrid procedure was 64% with antiarrhythmic drugs and 60% without antiarrhythmic drugs. Freedom from atrial tachyarrhythmia at latest follow-up after the hybrid procedure and redo catheter ablation was 77.8% with antiarrhythmic drugs and 74.1% without antiarrhythmic drugs. In patients with sinus rhythm restoration, mean left atrial diameter decreased from 54.4 ± 4.3 mm to 45.2 ± 4.1 mm (P < .001), and mean right atrial diameter decreased from 59.4 ± 3.9 mm to 54.9 ± 4.4 mm (P < .001). Postoperative pleural effusion was observed in 3 patients (11.1%), and no adverse events occurred during follow-up.

Conclusions

In patients with long-standing persistent AF and a dilated atrium, simultaneous hybrid ablation with the new biatrial lesion set, in combination with touch-up catheter ablation when necessary, can achieve promising results. More studies are needed to confirm these findings.

Subxiphoid Hybrid Epicardial-Endocardial Atrial Fibrillation Ablation and LAA Ligation: Initial Sub-X Hybrid MAZE Registry Results

OBJECTIVES

The aim of this study was to assess the safety and efficacy of a new subxiphoid hybrid epicardial-endocardial atrial fibrillation (AF) ablation and left atrial appendage (LAA) ligation approach for the treatment of persistent AF.

BACKGROUND

Surgical hybrid ablation procedures have shown promise for maintaining sinus rhythm versus catheter ablation but are associated with increased periprocedural adverse events.

METHODS

Patients with symptomatic persistent AF (n = 33, mean age 64 ± 9 years, 25 men) who had antiarrhythmic drug therapy or prior catheter ablation was unsuccessful were referred for hybrid epicardial-endocardial AF ablation and LAA exclusion. LAA closure was confirmed by transesophageal echocardiographic Doppler flow and/or computed tomographic angiography 1 to 3 months post-ligation. The incidence of atrial tachycardia or AF recurrence, LAA closure, thromboembolic events, and post-operative complications were assessed.

RESULTS

All 33 patients underwent successful LAA ligation with epicardial ablation of the posterior left atrial wall, as well as endocardial pulmonary vein isolation and cavotricuspid isthmus ablation. Freedom from atrial tachycardia or AF was 91% (20 of 22 patients) at 6 months, 90% (18 of 20 patients) at 12 months, 92% (11 of 12 patients) at 18 months, and 92% (11 of 12) at 24 months. There were no acute periprocedural complications (<7 days). Thirty-day adverse events included 2 patients with pericardial effusion requiring pericardiocentesis and 1 incisional hernia repair. There were no long-term complications, strokes, or deaths. LAA ligation was complete in 27 of 33 subjects (82%), with 6 subjects having leaks of <5 mm.

CONCLUSIONS

Subxiphoid hybrid epicardial-endocardial ablation with LAA ligation is feasible, safe, and effective. Future prospective studies are needed to validate these initial findings.

Catheter Ablation in the Treatment of Atrial Fibrillation

Catheter ablation (CA) of the pulmonary veins for atrial fibrillation (AF) is growing exponentially and is the most commonly performed electrophysiologic procedure. Initial descriptions focused on CA for paroxysmal AF, and now more recently expanded in application to persistent AF and those with comorbid heart failure. Efforts to improve success have and continue to address issues such as pulmonary vein "reconnection" following ablation through different ablative energy modalities, and the use of a "hybrid" surgical/endocardial combined approach in persistent forms of AF. Technologic advances as well are concurrently seeking to improve safety, particularly regarding the incidence of atrio-esophageal fistula in this seemingly ever-growing ablation population.

Deformable multimodal registration for navigation in beating-heart cardiac surgery

PURPOSE

Minimally invasive beating-heart surgery is currently performed using endoscopes and without navigation. Registration of intraoperative ultrasound to a preoperative cardiac CT scan is a valuable step toward image-guided navigation.

METHODS

The registration was achieved by first extracting a representative point set from each ultrasound image in the sequence using a deformable registration. A template shape representing the cardiac chambers was deformed through a hierarchy of affine transformations to match each ultrasound image using a generalized expectation maximization algorithm. These extracted point sets were matched to the CT by exhaustively searching over a large number of precomputed slices of 3D geometry. The result is a similarity transformation mapping the intraoperative ultrasound to preoperative CT.

RESULTS

Complete data sets were acquired for four patients. Transesophageal echocardiography ultrasound sequences were deformably registered to a model of oriented points with a mean error of 2.3 mm. Ultrasound and CT scans were registered to a mean of 3 mm, which is comparable to the error of 2.8 mm expected by merging ultrasound registration with uncertainty of cardiac CT.

CONCLUSION

The proposed algorithm registered 3D CT with dynamic 2D intraoperative imaging. The algorithm aligned the images in both space and time, needing neither dynamic CT imaging nor intraoperative electrocardiograms. The accuracy was sufficient for navigation in thoracoscopically guided beating-heart surgery.

Hybrid ablation versus transcatheter ablation for atrial fibrillation: A meta-analysis

BACKGROUND

Despite the successful creation of complex lesion sets during hybrid ablation (HA), reoccurrence of atrial fibrillation (AF), and/or atrial arrhythmia and procedural complications still occur. The main objective of this study was to compare the efficacy and safety between HA and transcatheter ablation (TA).

METHODS

We searched Pubmed, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL) database up to October 2017. Studies that satisfied our predefined inclusion criteria were included. Of the 894 records, 4 studies encompassing 331 patients were included in our study. We assessed pooled data using random-effect or fixed-effect model. The main endpoint was freedom of atrial arrhythmia after follow-up duration, secondary results were procedure time and intraoperative and postoperative adverse events. Similarly, tertiary outcomes were endocardial time, fluoroscopy time, and postoperative hospitalization.

RESULTS

Compared with TA, HA treatment through mini-thoracotomy access improved superiority in freedom of atrial arrhythmia after follow-up duration (odds ratio [OR] = 6.67, 95% confidence interval [CI]: 2.63-16.90), but HA increased the incidence of intraoperative and postoperative adverse events for AF patients (OR = 2.98, 95% CI: 1.30-6.83). HA through either mini-thoracotomy or transdiaphragmatic/subxiphoid access had longer procedure time and postoperative hospitalization than TA. However, endocardial time was shorter than TA.

CONCLUSIONS

For AF patients, HA possessed of an overall superior outcome using mini-thoracotomy way to TA. Although HA had longer procedure time, it yielded a reduction in endocardial time. Meanwhile, we should pay attention to the significantly high risk of intraoperative and postoperative adverse events that the HA generated.