Thrombus outcome data will be collected retrospectively during 2011-2012 as a historical baseline of SoC with oral VKA (Vitamin K Antagonist(s) for the treatment of patients with nonvalvular AF or atrial flutter documented with LA/ LAA thrombi on transesophag-eal echocardiography (TEE).

The study is a company-sponsored, global, multi-center, retrospective, non-interventional study. Patients who suffered from hemodynamically stable nonvalvular AF or atrial flutter and had a diagnosed LA/ LAA thrombus between January 1st, 2011 and December 31st, 2012 will be identified through screening and review of medical records and included in the registry. Retrospective patient data will be collected from May 2nd, 2013 to May 2nd, 2014. The observation of each patient will cover the period from the diagnosis of an LA/ LAA thrombus until the end-of-treatment TEE following the 3-12 week SoC anticoagulation (AC) therapy. If no end-of-treatment TEE has been performed during 3-12 weeks of AC therapy, the observational period will end at 12 weeks after diagnosis at the latest. If more than one TEE was performed during treatment, the thrombus outcome will be collected from the last TEE performed within 12 weeks of treatment start.

Inclusion Criteria:

• Men or women age ≥ 18 years at data recording
• Hemodynamically stable nonvalvular AF or atrial flutter
• Documented LA/ LA thrombus on TEE

Exclusion Criteria:

• Valvular AF ( ESC 2012 definition)
• History of cardiac thrombus confirmed on TEE
• Intracardiac tumors, e.g. atrial myxoma
• Active endocarditis

Patients who suffered from hemodynamically stable nonvalvular AF or atrial flutter and had a diagnosed LA/ LAA thrombus between January 1st, 2011 and December 31st, 2012.