A multicenter, randomized clinical trial compared two strategies for managing atrial fibrillation: one guided by transesophageal echocardiography (TEE) and another using conventional anticoagulation. The study enrolled 1222 patients with atrial fibrillation lasting more than two days. The primary outcome was the rate of embolic events (cerebrovascular accidents, transient ischemic attacks, and peripheral embolism) within eight weeks, while secondary outcomes included hemorrhagic events, death, and the success of restoring and maintaining sinus rhythm. The TEE group had a similar rate of embolic events (0.8%) compared to the conventional group (0.5%), but a significantly lower rate of hemorrhagic events (2.9% vs. 5.5%). The TEE group also had a shorter time to cardioversion (3.0 days vs. 30.6 days) and a higher rate of successful restoration of sinus rhythm (71.1% vs. 65.2%). There were no significant differences between the groups in death rates, maintenance of sinus rhythm, or functional status at eight weeks. The study found that TEE-guided management allowed for earlier, safer cardioversion with fewer hemorrhagic complications compared to conventional therapy. The conventional strategy required three weeks of anticoagulation before cardioversion, which led to longer times to cardioversion and more bleeding events. However, the TEE strategy was associated with a lower risk of bleeding and a shorter time to cardioversion, making it a clinically effective alternative to conventional therapy for patients undergoing elective cardioversion. The results suggest that TEE can be used to guide anticoagulation and cardioversion in patients with atrial fibrillation, reducing the need for prolonged anticoagulation and improving outcomes.A multicenter, randomized clinical trial compared two strategies for managing atrial fibrillation: one guided by transesophageal echocardiography (TEE) and another using conventional anticoagulation. The study enrolled 1222 patients with atrial fibrillation lasting more than two days. The primary outcome was the rate of embolic events (cerebrovascular accidents, transient ischemic attacks, and peripheral embolism) within eight weeks, while secondary outcomes included hemorrhagic events, death, and the success of restoring and maintaining sinus rhythm. The TEE group had a similar rate of embolic events (0.8%) compared to the conventional group (0.5%), but a significantly lower rate of hemorrhagic events (2.9% vs. 5.5%). The TEE group also had a shorter time to cardioversion (3.0 days vs. 30.6 days) and a higher rate of successful restoration of sinus rhythm (71.1% vs. 65.2%). There were no significant differences between the groups in death rates, maintenance of sinus rhythm, or functional status at eight weeks. The study found that TEE-guided management allowed for earlier, safer cardioversion with fewer hemorrhagic complications compared to conventional therapy. The conventional strategy required three weeks of anticoagulation before cardioversion, which led to longer times to cardioversion and more bleeding events. However, the TEE strategy was associated with a lower risk of bleeding and a shorter time to cardioversion, making it a clinically effective alternative to conventional therapy for patients undergoing elective cardioversion. The results suggest that TEE can be used to guide anticoagulation and cardioversion in patients with atrial fibrillation, reducing the need for prolonged anticoagulation and improving outcomes.