Percutaneous left atrial appendage occlusion: A review of current devices, clinical evidence, patient selection, and post procedural antithrombotic management

Stroke is a major driver of increased morbidity and mortality in patients with non-valvular atrial fibrillation (NVAF). While systemic oral anticoagulation (OAC) continues to be the mainstay for stroke reduction therapy in patients with NVAF, several barriers prevent the sustained long-term use of OAC, including increased risk of bleeding, non-compliance, cost, drug-drug interactions, and the need for ongoing laboratory testing. Given the need for continued stroke reduction therapies in patients who are intolerant of or non-compliant with OAC, percutaneous left atrial appendage (LAA) occlusion (LAAO) has emerged as a nonpharmacologic alternative to OAC. The development of percutaneous LAAO techniques is based on data suggesting that more than 90% of thrombi in patients with NVAF originate in the LAA. Two percutaneous LAAO devices are currently in widespread clinical use: Watchman (United States and Europe) and the Amplatzer type of devices (Europe); randomized trial data exist only for the Watchman device. Multiple randomized and nonrandomized trials and registries have demonstrated the safety and effectiveness of LAAO in patients who are suitable for short-term anticoagulation using a variety of post-procedural antithrombotic strategies. Ongoing randomized clinical trials on LAAO are focused on OAC-ineligible patients to compare efficacy of LAAO devices against a multitude of antithrombotic options. This review aims to discuss the rationale and evidence for LAAO and post procedural antithrombotic strategies and opportunities for research examination. In addition, we discuss the need for continued investigation of LAAO in populations not well represented in clinical trials or registries, including women, older patients, and underrepresented racial and ethnic groups.