In patients with chronic atrial fibrillation (AF), the direct reason of thromboembolism is the formation and migration of thrombus in left atrium (LA) and/or left atrial appendage (LAA) .

• 左心房/左心耳(LA/LAA)血栓形成和脱落是造成慢性心房颤动(房颤，AF)患者血栓栓塞并发症的直接原因。 服用华法林(华法令，Warfarin)可明显降低AF栓塞事件发生率。