@dreamtlc I just read your question and am unsure of your understanding. I hope you won't mind my statement. It's intended to correct what might (maybe not) be a misconception about the Watchman. The Watchman is a mesh, sort of like a thimble of wire, placed tight up against the rear wall of the Left Atrial Appendage (LAA). Its purpose is to prevent clots from leaking out of the LAA during, or weeks after, a bout of AF (atrial fibrillation). The risk is that a clot forming due to poor circulation in the volume of the LAA might become dislodged again, either due to happenstance or when normal sinus rhythm resumes and its higher flow and force wash the clot(s) out of the LAA and down into the left ventricle. From there, they would be forced up into the aorta and out to kidneys, the brain, the lungs, or to the heart's own arteries, where it will cause a thromboembolic event.

After a Watchman is installed, it gets infiltrated with, and closed off with, endothelial tissue which is meant to seal the front opening of the LAA...roughly speaking. This process, and any security if offers, does NOT prevent, OR encourage, any further atrial fibrillation. The Watchman is inert, and is strictly meant for security against clot formation inside the LAA. So, people who get a Watchman installed, and people who have a pacemaker installed, or an ICD, are not immune from arrhythmias of all kinds. They can still happen because those are electrical disorders, not blood flow problems that might cause clotting.

Again, if this is all well understood, please excuse me. I'm just going by the way you formulated your question.