The increasing interest in left atrial appendage occlusion (LAAO) for ischaemic stroke prevention in atrial fibrillation (AF) fuels the need for more clinical data on the safety and effectiveness of this therapy. Besides an assessment of the effectiveness of the therapy in specific patients groups, comparisons with pharmacological stroke prophylaxis, surgical approaches, and other device-based therapies are warranted. This paper documents the consensus reached among clinical experts in relevant disciplines from Europe and North America, European cardiology professional societies, and representatives from the medical device industry regarding definitions for parameters and endpoints to be assessed in clinical studies. Adherence to these definitions is proposed in order to achieve a consistent approach across clinical studies on LAAO among the involved stakeholders and various clinical disciplines and thereby facilitate continued evaluation of therapeutic strategies available.

Background and Aims: Residual leaks are not infrequent after left atrial appendage occlusion. However, there is still uncertainty regarding their prognostic implications. The aim of this study is to evaluate the impact of residual leaks after left atrial appendage occlusion. Methods: A literature search was conducted until 19 February 2023. Residual leaks comprised peri-device leaks (PDLs) on transoesophageal echocardiography (TEE) or computed tomography (CT), as well as left atrial appendage patency on CT. Random-effects meta-analyses were performed to assess the clinical impact of residual leaks. Results: Overall 48 eligible studies (44 non-randomized/observational and 4 randomized studies) including 61 666 patients with atrial fibrillation who underwent left atrial appendage occlusion were analysed. Peri-device leak by TEE was present in 26.1% of patients. Computed tomography-based left atrial appendage patency and PDL were present in 54.9% and 57.3% of patients, respectively. Transoesophageal echocardiography-based PDL (i.e. any reported PDL regardless of its size) was significantly associated with a higher risk of thromboembolism [pooled odds ratio (pOR) 2.04, 95% confidence interval (CI): 1.52–2.74], all-cause mortality (pOR 1.16, 95% CI: 1.08–1.24), and major bleeding (pOR 1.12, 95% CI: 1.03–1.22), compared with no reported PDL. A positive graded association between PDL size and risk of thromboembolism was noted across TEE cut-offs. For any PDL of >0, >1, >3, and >5 mm, the pORs for thromboembolism were 1.82 (95% CI: 1.35–2.47), 2.13 (95% CI: 1.04–4.35), 4.14 (95% CI: 2.07–8.27), and 4.44 (95% CI: 2.09–9.43), respectively, compared with either no PDL or PDL smaller than each cut-off. Neither left atrial appendage patency, nor PDL by CT was associated with thromboembolism (pOR 1.45 and 1.04, 95% CI: 0.84–2.50 and 0.52–2.07, respectively). Conclusions: Peri-device leak detected by TEE was associated with adverse events, primarily thromboembolism. Residual leaks detected by CT were more frequent but lacked prognostic significance.

A significant proportion of patients who suffer from atrial fibrillation and are in need of thromboembolic protection are not treated with oral anticoagulation or discontinue this treatment shortly after its initiation. This undertreatment has not improved sufficiently despite the availability of direct oral anticoagulants which are associated with less major bleeding than vitamin K antagonists. Multiple reasons account for this, including bleeding events or ischaemic strokes whilst on anticoagulation, a serious risk of bleeding events, poor treatment compliance despite best educational attempts or aversion to drug therapy. An alternative interventional therapy, which is not associated with long-term bleeding and is as effective as vitamin K anticoagulation, was introduced over 20 years ago. Because of significant improvements in procedural safety over the years left atrial appendage closure, predominantly achieved using a catheter-based, device implantation approach, is increasingly favoured for the prevention of thromboembolic events in patients who cannot achieve effective anticoagulation. This management strategy is well-known to the interventional cardiologist/electrophysiologist but is not more widely appreciated within cardiology or internal medicine. This article introduces the devices and briefly explains the implantation technique. The indications and device follow-up are more comprehensively described. Almost all physicians who care for adult patients will have many with atrial fibrillation. This practical guide, written within guideline/guidance boundaries, is aimed at those non-implanting physicians who may need to refer patients for consideration of this new therapy, which is becoming increasingly popular.

Atrial fibrillation (AF) is associated with an increased risk of stroke and systemic embolism, and the left atrial appendage (LAA) has been identified as a principal source of thromboembolism in these patients. While oral anticoagulation is the current standard of care, LAA closure (LAAC) emerges as an alternative or complementary treatment approach to reduce the risk of stroke or systemic embolism in patients with AF. Moderate-sized randomized clinical studies have provided data for the efficacy and safety of catheter-based LAAC, largely compared with vitamin K antagonists. LAA device iterations, advances in pre- and peri-procedural imaging, and implantation techniques continue to increase the efficacy and safety of LAAC. More data about efficacy and safety of LAAC have been collected, and several randomized clinical trials are currently underway to compare LAAC with best medical care (including non-vitamin K antagonist oral anticoagulants) in different clinical settings. Surgical LAAC in patients with AF undergoing cardiac surgery reduced the risk of stroke on background of anticoagulation therapy in the LAAOS III study. In this review, we describe the rapidly evolving field of LAAC and discuss recent clinical data, ongoing studies, open questions, and current limitations of LAAC.

Current guidelines suggest that asymptomatic atrial fibrillation (AF) is independently associated with increased risks of stroke and mortality compared with symptomatic AF. Considering that recent investigations have provided conflicting results, the present study aimed to evaluate the association between symptom status and clinical outcomes in patients with AF. Medline, Cochrane Library, and Scopus were searched until 25 March 2024. Triple-independent study selection, data extraction and quality assessment were performed. Evidence was pooled using random-effects meta-analyses. Thirty-six studies (217 850 participants) were included. Based on the frequentist analysis, symptomatic individuals had no significant difference in the risk of all-cause mortality [hazard ratio (HR) .97, 95% confidence interval (CI) .80–1.17], cardiovascular mortality (HR 1.04, 95% CI .72–1.49), thromboembolism (HR 1.06, 95% CI .87–1.28), stroke (HR 1.06, 95% CI .84–1.34), hospitalization (HR 1.34, 95% CI .89–2.02), and myocardial infarction (HR .98, 95% CI .70–1.36), compared to the asymptomatic group. Symptomatic patients had a 33% increased risk of new-onset heart failure (HR 1.33, 95% CI 1.19–1.49) and a 30% lower risk of progression to permanent AF (HR .70, 95% CI .54–.89). The Bayesian analysis yielded comparable results, yet the association between symptom status and new-onset heart failure was not significant (HR 1.27, 95% credible interval .76–1.93; Bayes factor = 1.2). Symptomatic patients had higher odds of receiving antiarrhythmic drugs (odds ratio [OR] 1.64, 95% CI 1.33–2.03) and ablation therapy (OR 1.47, 95% CI 1.06–2.05) compared to asymptomatic cases. The risk of major clinical outcomes did not differ between individuals with and without AF-related symptoms. Asymptomatic patients had a greater hazard of progression to permanent AF. Major clinical outcomes in patients with symptomatic vs. asymptomatic atrial fibrillation. AF, atrial fibrillation; CI, confidence interval; CrI, credible interval; HR, hazard ratio; OR, odds ratio. * A two-tailed P-value <.05 was considered statistically significant