Impact of Left Atrial Appendage Closure on LAA Thrombus Formation and Thromboembolism After LAA Isolation

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

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

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

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

Catheter ablation for non-paroxysmal atrial fibrillation. A review

Atrial fibrillation (AF), the most common cardiac arrhythmia is associated with increased morbidity and mortality. The higher mortality is due to the risk of heart failure and cardioembolic events. This in-depth review focuses on the strategies and efficacy of catheter ablation for non-paroxysmal atrial fibrillation. The main medical databases were searched for contemporary studies on catheter ablation for non-paroxysmal AF. Catheter ablation is currently proven to be the most effective treatment for AF and consists of pulmonary vein isolation as the cornerstone plus additional ablations. In terms of SR maintenance, it is less effective in non-paroxysmal AF than in paroxysmal patients. but the clinical benefit in non-paroxysmal patients is substantially higher. Since pulmonary vein isolation is ineffective, a variety of techniques have been developed, e.g. linear ablations, ablation of complex atrial fractionated electrograms, etc. Another paradox consists in the technique of catheter ablation. Despite promising results in early observation studies, further randomized studies have not confirmed the initial enthusiasm. Recently, a new approach, pulsed-field ablation, appears promising. This is an in-depth summary of current technologies and techniques for the ablation of non-paroxysmal AF. We discuss the benefits, risks and implications in the treatment of patients with non-paroxysmal AF.

Long-term outcomes of left atrial appendage isolation using cryoballoon in persistent atrial fibrillation

AIMS

There is an increasing trend evaluating the role of non-pulmonary vein (PV) triggers to improve ablation outcomes in persistent atrial fibrillation (AF) as pulmonary vein isolation (PVI) strategy alone has modest outcomes. We investigated the long-term safety and efficacy of left atrial appendage isolation (LAAi) in addition to PVI using cryoballoon (CB) in persistent AF.

METHODS AND RESULTS

In this multicentre retrospective analysis, we included a total of 193 persistent AF patients (mean age: 60 ± 11 years, 50.3% females) who underwent PVI and LAAi using CB. Baseline and follow-up data including electrocardiography (ECG), 24 h Holter ECGs, and echocardiography were recorded for all patients. Atrial tachyarrhythmia (ATa) recurrence was defined as the detection of AF, atrial flutter, or atrial tachycardia (≥30 s) after a 3-month blanking period. At a median follow-up of 55 (36.5-60.0) months, 85 (67.9%) patients with PVI + LAAi were in sinus rhythm after the index procedure. Ischaemic stroke/transient ischemic attack occurred in 14 (7.2%) patients at a median of 24 (2-53) months following catheter ablation. Multivariate regression analysis revealed heart failure with preserved ejection fraction [hazard ratio (HR) 2.29, 95% confidence interval (CI) 1.04-5.02; P = 0.038], male gender (HR 0.53, 95% CI 0.29-0.96; P = 0.037), and LA area (HR 1.04, 95% CI 0.53-1.32; P = 0.023) as independent predictors of ATa recurrence.

CONCLUSION

Our findings demonstrated that the LAAi + PVI strategy using CB had acceptable long-term outcomes in patients with persistent AF. Systemic thrombo-embolic events are an important concern throughout the follow-up, which were mostly observed in case of non-adherence to anticoagulants.

Intra- and Postprocedural Multimodality Imaging in Atrial Fibrillation

Multi-modality imaging plays critical roles during and after procedures associated with atrial fibrillation. Transesophageal echocardiography is an invaluable tool for left atrial appendage occlusion during the procedure and at follow-up. Both cardiac computed tomography and cardiac magnetic resonance contribute to postprocedural evaluation of pulmonary vein isolation ablation. The present review is the second of a 2-part series where we discuss the roles of cardiac imaging in the evaluation and management of patients with atrial fibrillation, focusing on intraprocedural and postprocedural assessment, including the clinical evidence and outcomes data supporting this future applications.

High-density activation map of atrial tachycardia within left atrial appendage

Identification of the critical isthmus of the reentrant tachycardia is essential to maximize the effect of catheter ablation (CA) and to minimize the myocardial injury of CA. An 81-year-old woman presented recurrent palpitations after CA of atrial fibrillation (AF) and atrial tachycardia (AT). She had moderate aortic valve stenosis and coronary artery disease. She had received a pulmonary vein isolation, left atrial (LA) posterior wall isolation, and LA anterior linear ablation for atrial fibrillation 1 year prior. At the start of the procedure, she was in sinus rhythm. Atrial burst pacing induced an AT (230msec). High-density mapping revealed a figure-of-eight activation pattern within the LA appendage (LAA), accounting for 99% of the tachycardia cycle length. The critical isthmus was identified at the mid LAA and the local electrogram of the critical isthmus was not fractionated. A single radiofrequency application at the critical isthmus of the AT, terminated the AT. She was free from any ATs for 28 months. Radiofrequency ablation of the localized reentrant AT was usually performed targeting long fractionated electrograms. In our case, the local electrogram at the critical isthmus was not fragmented compared with the LAA distal part. Long fractionated electrograms were recorded at a more distal part of the LAA than the common isthmus and we could avoid the potential risk of a perforation. A recent developed 3-dimensional electro-anatomical mapping system can identify the critical isthmus and allow us to select a new therapeutic strategy for a critical isthmus ablation of an AT within the LAA.

Current evidence on the safety and efficacy of combined atrial fibrillation ablation and left atrial appendage closure

PURPOSE OF REVIEW

Combined atrial fibrillation (AF) ablation and left atrial (LA) appendage (LAA) closure (LAAC) has been practiced for management of both the symptoms and the high stroke risk of AF. The purpose of this review is to review recent evidence regarding the combined procedure.

RECENT FINDINGS

Newly acquired long-term data of combined AF ablation and LAAC supplied satisfactory evidence on the safety and efficacy of the combined procedure. Studies also showed LA structural remodeling following combined procedure was mainly affected by sinus rhythm status post catheter ablation, not by LAAC. A cost-effectiveness study revealed that combined procedure was a cost-effective therapeutic option in symptomatic AF patients with high stroke and bleeding risk. Due to recent evidence of high incidences of LAA thrombus formation after LAA electrical isolation (LAAEI) and benefit of LAAC after LAAEI, an extended combined procedure of standard AF ablation plus LAAEI and LAAC was considered as a potential therapeutic option for persistent AF patients with high stroke risk.

SUMMARY

In conclusion, combined AF ablation and LAAC serve as a promising option for patients with symptomatic AF and high risk of stroke and/or bleeding.

Long-Term Stroke Risk in Patients Undergoing Left Atrial Appendage Ablation With and Without Complete Isolation

Background: Catheter ablation (CA) for atrial fibrillation (AF), may require ablation beyond the pulmonary veins. Prior data suggest that additional LA ablation, particularly left atrial appendage (LAA) ablation, may alter atrial function leading to increased risk of ischemic stroke or transient ischemic attack (IS/TIA). We sought to study the long-term risk of IS/TIA in patients receiving ablation at the LAA compared to those receiving PVI alone and those receiving PVI with additional non-LAA locations.

Methods: 350 patients who underwent CA for AF from 2008 to 2018 were included in the study. Locations of ablation in LA evaluated were the posterior wall, anterior wall, inferior wall, inter-atrial septum, lateral wall and the left atrial appendage (LAA). Patients undergoing LAA ablation were further divided as complete isolation (LAAi) and without complete isolation (LAAa).

Results: Mean follow up of 4.8 years. In entire cohort, risk of IS/TIA was 1.62/100 patient-years (pys). The risk was highest in patients with LAAi (3.81/100 pys), followed by ablation LAAa (3.74/100 pys). Amongst all LA locations, only LAAi (HR 3.32, p = 0.03) and LAAa (HR 3.18, p = 0.02) were statistically significant predictors of IS/TIA after adjusting for OAC (Oral anticoagulant) use and baseline CHA₂DS₂VASc score.

Conclusions: During long term follow-up, only ablation at the left atrial appendage with and without complete isolation was independently associated with an increased risk of IS/TIA in patients undergoing CA for AF. Potential strategies to reduce stroke risk, such as LAA closure, should be considered in these patients.

Impact of Catheter Ablation on Stroke, Cognitive Decline and Dementia

AF has been consistently associated with multiple forms of dementia, including idiopathic dementia. Outcomes after catheter ablation for AF are favourable and patients experience a better quality of life, arrhythmia-free survival, and lower rates of hospitalisation compared to patients treated with antiarrhythmic drugs. Catheter ablation is consistently associated with lower rates of stroke compared to AF management without ablation in large national and healthcare system databases. Multiple observational trials have shown that catheter ablation is also associated with a lower risk of cognitive decline, dementia and improved cognitive testing that can be explained through a variety of pathways. Long-term, adequately powered, randomised trials are required to define the role of catheter ablation in the management of AF as a means to lower the risk of cognitive decline, stroke and dementia.

Long-Term Effect of Left Atrial Appendage Occlusion in Treating Patients with Previous Ischemic Stroke on the Disease Recurrence

Methods

A total of 120 patients with IS admitted to Tangdu Hospital from July 2016 to September 2017 were grouped into the control group (n = 60) and the observation group (n = 60). Patients in the control group were only treated with thrombolytics and anticoagulants while those in the observation group were treated with both drugs and LAAO. Transesophageal echocardiography (TEE) was performed to observe the occlusion of LAA in patients in the observation group after 45 d and 6 months, respectively. Clinical outcomes in two groups were compared from the following aspects: recurrence of IS, incidence of systemic embolism, and the 3-year recurrence-free survival (RFS). The 3-year IS recurrence of patients was compared by Fisher's exact test.

Results

No significant differences were observed at baseline levels (age, sex, etc.) between the observation group and control group (p > 0.05). During follow-up visit of 45 d and 6 months, all occluders met the efficacious occludsion criteria. The results of TEE at 45 d after LAAO showed that 50% of patients (30/60) in the observation group had complete occlusion of LAA. The results of TEE at 6 months after LAAO suggested that 58.3% of patients (35/60) had complete occlusion of LAA. IS recurrence in the observation group (3.33%, 2/60) was significantly lower than that in the control group (18.33%, 11/60), with the difference presenting statistical significance (p = 0.008). Incidence of systemic embolism in the observation group (1.67%, 1/60) was markedly lower than that in the control group (13.33%, 11/60) (p = 0.014). The average RFS in the observation group (31.97 months, 95% CI: 27.50~32.31 months) was notably longer than that in the control group (29.91 months, 95% CI: 29.85~32.92 months) (p < 0.05). The 3-year IS recurrence of patients between two groups compared by Fisher's exact test showed significant differences (1 year: p = 0.014, 2 year: p = 0.008, 3 year: p = 0.008).

Conclusion

Regarding patients with previous IS who had poor response to thrombolytics and anticoagulants, LAAO could effectively decrease recurrence of IS and incidence of systemic embolism and prolong RFS of patients. LAAO was, therefore, an alternative for patients with high IS recurrence risk.

Left Atrial Isolation and Appendage Occlusion in Patients With Atrial Fibrillation at End-Stage Left Atrial Fibrotic Disease

[Figure: see text].