Left Atrial Appendage Occlusion

This is a single-center, prospective, single-arm clinical trial designed to evaluate the safety and efficacy of pulsed field ablation (PFA) after left atrial appendage occlusion (LAAO) in patients with non-valvular atrial fibrillation (AF). The trial will include patients who have undergone successful LAAO and have symptomatic AF that is refractory to or intolerant of class I or III antiarrhythmic drugs. The primary objective is to assess the effectiveness of PFA in preventing AF recurrence and its safety, including the occurrence of serious adverse events. Patients will be followed up for 12 months post-procedure to evaluate outcomes such as recurrence of AF, complications, and device-related issues.

Objectives: This pilot study aims to evaluate the safety and efficacy of left atrial appendage occlusion (LAAO) in dialysis patients and atrial fibrillation (AF) to establish a novel stroke prevention strategy and determine an optimal post-occlusion antithrombotic regime. Page 3 of 50 Hypothesis: The study tests the hypotheses that LAAO is safe for dialysis patients, that a single antiplatelet regimen postprocedure is safe, and that LAAO effectively reduces the composite endpoint of stroke/transient ischemic attack and major bleeding compared to standard care. Instruments: The study employs a multicenter, single-arm prospective registry design. Eligible participants, aged ≥18 with documented AF and ESRF on peritoneal dialysis (PD) or hemodialysis (HD), will undergo LAAO using the Watchman Flx PRO device. Propensity score matched historical cohort from dialysis registry will be identified for comparison. Main Outcome Measures: The primary endpoint is the composite of stroke/transient ischemic attack/systemic embolism and non-procedural-related major bleeding at one year. Secondary endpoints include individual rates of these events, procedural safety and device occlusion effectiveness. Data Analysis and Expected Results: Statistical analysis will involve descriptive statistics, chi-squared tests, and propensity score matching. A p-value of \<0.05 will be deemed significant. The pilot study anticipates a low peri-procedural complication rate (≤5%) and confirms LAAO's efficacy in stroke and major bleeding reduction in Chinese PD and HD patients compared to standard care. This data will inform the design of a larger randomized controlled trial aimed at validating LAAO as a safe alternative for AF management in dialysis populations.

Percutaneous left atrial appendage closure (LAAC) is an effective strategy for stroke prevention in patients with non-valvular atrial fibrillation (NVAF). Standard procedure requires general anesthesia, transesophageal echocardiography (TEE) guidance. With the experience accumulation, LAAC can be successfully completed in many centers under local anesthesia, the guidance of X-ray and transthoracic echocardiography (TTE), also known as minimalist procedure. Our center was one of the earliest to carry out minimalist procedure worldwide. At present, expert consensus suggests that minimalist procedure is feasible in experienced centers, but the relevant evidence is insufficient. Some single-arm studies have shown that minimalist procedure is safe and effective. However, there is currently a lack of direct evidence to compare the strengths and weaknesses of these two LAAC procedures. The goal of the study was to compare the effectiveness and safety of minimalist procedure and standard procedure for LAAC in patients with NVAF.

Leadless pacemakers (LP) are safe and effective alternatives to transvenous pacemakers in selected patients. Implantation is performed with a large caliber delivery catheter. Care must be taken in introducing the delivery catheter into the patient's venous system. Implantation in patients with small body habitus demands extra caution to avoid vascular injury and cardiac perforation. Negotiating the large caliber delivery catheter into the desired implant position may also be more difficult in small right ventricles. In a previous report of Micra leadless pacemakers, it was found that low BMI was associated with poor efficacy and safety. The Aveir leadless pacemaker is a new leadless pacemaker that has obtained FDA approval and is commercially available in Hong Kong. It features a screw-in fixation mechanism, in contrast to the passive fixation of Micra. Most of its efficacy and safety data comes from a Western population. It would be important to study its efficacy and safety in an Asian population, who tend to have smaller body builds, hence more prone to complications. In recent papers regarding the Micra leadless pacemaker, it was found that tricuspid regurgitation (TR) could be a result, especially if the implant was too close to the tricuspid valve. Given the almost 50% longer device dimension of the Aveir VR compared with the Micra leadless pacemaker (38mm vs 26mm), it is expected that the device mechanical interaction with tricuspid valve dysfunction can be more common. In the smaller hearts of an Asian population, it would be important to study the TR progression after device implantation. About half of the patients implanted with leadless pacemakers were having concomitant atrial fibrillation and thus were at risk for thromboembolic events. Left atrial appendage occlusion was an effective procedure for stroke prevention in patients with atrial fibrillation. Because one patient often has indication for both LAAO and leadless pacemaker, combining them into the same procedure is appealing. The combined procedure can be performed with one single access. The imaging used to guide LAAO implantation can also be used to guide leadless pacemaker implantation to improve the procedure safety. This study is a prospective observational study. Patients indicated for combined leadless pacemaker and left atrial appendage occlusion will be enrolled. Patients would fulfill guideline Class I and Class II indication for leadless pacemaker. The decision for left atrial appendage occlusion will be a shared decision-making process between the physician and patient. The consideration is usually based on patient's bleeding risk, tolerability for oral anticoagulation and patient preference.

The objective of this trial is to compare two different commercially available left atrial appendage occlusion (LAAO) devices in patients with non-valvular Atrial fibrillation/ atrial flutter (AF) at increased risk for stroke with regard to safety and efficacy. The investigators hypothesize that LAAO using the LAmbre occlusion device (Lifetech Scientific, Shenzhen, China) is non-inferior to LAAO using the AMPLATZER Amulet occlusion device (Abbott Medical, Chicago, ILL, USA) with regards to the primary endpoint, which is peri-device leak (PDL) size 3 months after LAAO, as assessed with transesophageal echocardiography (TOE) in patients with non-valvular AF.