Study Overview: This study, called SAFE HV, looks at how safe and effective it is when one doctor performs multiple Left Atrial Appendage Occlusion (LAAO) device implantations in a single day. LAAO is a medical procedure that helps prevent strokes in patients with heart issues. The study focuses on doctors who do eight or more of these procedures in one day.

Background: The Watchman FLX™ device has been used since 2009 to help people who can't take blood thinners. This study will see if doing many procedures in one day is as safe as doing them one at a time. It will also gather information to help doctors improve their procedures.

• The study is observational, meaning researchers just watch and collect data; no one is given new treatments.
• Participants must be at least 18 years old and willing to attend follow-up evaluations.
• It is important that participants consent to being part of the study.

Note: People in other clinical trials or those with reasons they should not have the LAAO procedure cannot join this study.