This clinical trial is focused on patients with atrial fibrillation, a common heart condition that causes an irregular and often rapid heart rate. The study is investigating whether patients who have undergone a specific type of heart surgery, known as surgical closure of the left atrial appendage, can safely stop taking blood-thinning medications. These medications, also known as anticoagulants, help prevent blood clots that can lead to strokes. The trial will compare the risks of stroke, blood clots, and major bleeding events in patients who continue taking these medications versus those who do not.

The medications being studied include Warfarin Sodium, a vitamin-K antagonist, and several direct factor Xa inhibitors: Rivaroxaban, Apixaban, and Edoxaban. Additionally, Dabigatran, a direct thrombin inhibitor, is also part of the study. These medications are commonly used to prevent blood clots in patients with atrial fibrillation. Some participants in the study will receive a placebo, which is a substance with no active medication, to help researchers understand the effects of the actual medications.

The study will last for a period of up to 48 months, during which participants will be monitored for any occurrences of stroke, blood clots, or bleeding events. The goal is to determine if it is safe for patients to discontinue anticoagulant therapy after their heart surgery. This research could potentially lead to changes in how patients with atrial fibrillation are treated following surgery, aiming to improve their quality of life and reduce the risk of complications associated with long-term use of blood-thinning medications.