Table 2.

Left atrial appendage as a source of thrombi in nonatrial fibrillation.

(i) Hypothesis is based on a landmark study by Blackshear and Odell [31]
(ii) Findings from studies in settings of operation, autopsy, or transesophageal echocardiography were combined
(iii) 23 studies including close to 5,000 subjects with rheumatic or nonrheumatic AF* were reviewed
(iv) Thrombi presented in the appendage but extending into the atrium was classified as a LAA** thrombus
(v) While 57% of atrial thrombi in rheumatic AF occurred in the appendage, 91% of left atrial thrombi were located in the atrial appendage in nonrheumatic AF (P < .0001)
(vi) Many have pointed out that merely finding a thrombus in the LAA does not prove that it is the source of cardio-emboli in AF-related ischemic stroke [32]
(vii) This study set the stage to investigate the benefit of LAA occlusion in reducing nonrheumatic AF-related stroke burden

*AF: atrial fibrillation; **LAA: left atrial appendage.