Tzikas, Apostolos

Abstract Since its introduction in 2002, left atrial appendage closure (LAAC) has rapidly expanded as an alternative to anticoagulation in patients with atrial fibrillation at high risk of stroke. Harmonized processes for data collection, analysis, and reporting in LAAC trials are essential to enhance research quality and improve clinical practice. The Left Atrial Appendage Academic Research Consortium (LAARC) initiative is an independent collaboration of academic research organizations, cardiology and neurology experts, clinical trialists, and regulatory authorities from the USA, Europe, and Asia. The consortium engaged clinical experts, regulators—including the US Food and Drug Administration (FDA), European Notified Bodies, and Japan’s Pharmaceuticals and Medical Devices Agency (PMDA)—and industry leaders to define standardized study elements and endpoints for LAAC trials. Key considerations included alignment with prior Academic Research Consortium initiatives, procedural and mechanistic insights, and clinical relevance. Consensus definitions were proposed for mortality, stroke, bleeding, and device performance, along with composite endpoints for safety and effectiveness. The proposed LAARC consensus definitions aim to standardize endpoint reporting, improve comparability across studies, and support regulatory and clinical trial applications for this evolving therapy through broad dissemination in the peer-reviewed literature.

Abstract Background and Aims 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. Methods 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. Results 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. Conclusions 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.

Abstract 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.