The Left Atrial Appendage, Including LAA Occlusion Devices Line Watchman, Amulet, and Lariat

MRI-based training model for left atrial appendage closure

PURPOSE

Percutaneous closure of the left atrial appendage (LAA) reduces the risk of embolic stroke in patients with atrial fibrillation. Thereby, the optimal transseptal puncture (TSP) site differs due to the highly variable anatomical shape of the LAA, which is rarely considered in existing training models. Based on non-contrast-enhanced magnetic resonance imaging (MRI) volumes, we propose a training model for LAA closure with interchangeable and patient-specific LAA enabling LAA-specific identification of the TSP site best suited.

METHODS

Based on patient-specific MRI data, silicone models of the LAAs were produced using a 3D-printed cast model. In addition, an MRI-derived 3D-printed base model was set up, including the right and left atrium with predefined passages in the septum, mimicking multiple TSP sites. The various silicone models and a tube mimicking venous access were connected to the base model. Empirical use of the model allowed the demonstration of its usability.

RESULTS

Patient-specific silicone models of the LAA could be generated from all LAA patient MRI datasets. The influence of various combinations regarding TSP sites and LAA shapes could be demonstrated as well as the technical functionality of the occluder system. Via the attached tube mimicking the venous access, the correct handling of the deployment catheter even in case of not optimal puncture site could be practiced.

CONCLUSION

The proposed contrast-agent and radiation-free MRI-based training model for percutaneous LAA closure enables the pre-interventional assessment of the influence of the TSP site on the access of patient-specific LAA shapes. A straightforward replication of this work is measured by using clinically available imaging protocols and a widespread 3D printer technique to build the model.

Combination of percutaneous left appendage epicardial ligation and endo-epicardial atrial fibrillation ablation

Introduction

Atrial fibrillation (AF) is the main cause of cardioembolic stroke. In high-bleeding-risk patients, long-life anticoagulation therapy is not permitted, and left atrial appendage (LAA) closure may be considered. LAA is also a critical substrate for AF. Epicardial LAA occlusion has several advantages: LAA ligation results in a favorable electrical and structural atrial remodeling, which decreases AF recurrence. Endocardial ablation alone is not efficient for all patients, and new evidence shows better outcomes in patients affected by persistent AF after a combined hybrid endo-epicardial ablation. Considering the synergic potential of these techniques, in this case series, they were both combined in a single procedure.

Methods and results

We describe the treatment of 5 patients referred for refractory AF ablation and LAA closure. All patients had high thrombotic and previous major hemorrhage, with relative contraindication to life-long therapy with anticoagulation. A combined procedure of LAA ligation and endo-epicardial ablation was scheduled with short-term anticoagulation. LAA closure was performed with an epicardial approach using the LARIAT system. Then, LA mapping and ablation were performed, endocardially and then epicardially.All procedures were concluded without complications.At follow-up, in all patients, transesophageal echocardiography showed the complete occlusion of the LAA; therefore, anticoagulation therapy was interrupted. All patients were asymptomatic, and in the sinus rhythm, no hemorrhage or ischemic events occurred.

Conclusion

The combination of percutaneous LAA ligation and endo-epicardial ablation was revealed to be feasible and safe and might represent a new approach for the treatment of refractory AF in patients with indication of LAA occlusion.

Left atrial appendage occlusion using hydrogel coils in a child

Left atrial appendage occlusion in young children has not been reported before. Herein, we describe a successful occlusion using hydrogel coils in a toddler. The decision to occlude the appendage was made to mitigate the potential risk of systemic thromboembolism, given the child's unusual anatomy.

Outcomes of cardiac surgery with left atrial appendage occlusion versus no Occlusion, direct oral Anticoagulants, and vitamin K Antagonists: A systematic review with Meta-analysis

Surgical left atrial appendage occlusion (LAAO) is being used increasingly in the setting of atrial fibrillation but has been associated with procedural complications. This systematic review and meta-analysis compared the outcomes of surgical LAAO with those of no LAAO and the use of direct oral anticoagulants (DOACs) and vitamin K antagonists (VKAs) using the PRISMA guidelines. A literature search was undertaken for relevant studies published between January 1, 2003, and August 15, 2021. Primary clinical outcomes were all-cause mortality, embolic events, and stroke. Secondary clinical outcomes included major adverse cardiac events (MACE), postoperative atrial fibrillation, postoperative complications, reoperation for bleeding, and major bleeding. There was a statistically significant 34% reduction in incidence of embolic events (odds ratio [OR] 0.66, 95% confidence interval [CI] 0.57–0.77, p < 0.001) and a significant 42% reduction in risk of MACE (OR 0.58, 95% CI 0.38–0.88, p = 0.01) in patients who underwent LAAO.Surgical LAAO has the potential to reduce embolic events and MACE in patients undergoing cardiac surgery for atrial fibrillation. However, complete replacement of DOACs and warfarin therapy with surgical LAAO is unlikely despite its non-inferiority in terms of minimizing all-cause mortality, embolic events, MACE, major bleeding, and stroke in patients on oral anticoagulation therapies.