View on the left atrial appendage thrombosis on the heart autopsy

Introduction. Thromboembolic syndrome is a dangerous complication of atrial fibrillation (AF). Left atrial appendage (LAA) is the most frequent location of the thrombus formation in AF. Enlargement of the LAA, special anatomical forms of the appendage are accepted as a risk factors of the LAA thrombosis.

Aim: to assess the revealing macro-/microthrombosis LAA in dependence of the morphological form of the appendage in autopsy.

Methods. 85 cadaveric hearts were investigated. LAA was measured in three dimensions, the anatomical form of the LAA were estimated by Wang et al. classification. Histological investigation of the LAA slices was made in Hematoxylin Eosin colouring.

Results. Macrothrombosis was revealed in 4 LAA. Microthrombus in the LAA were revealed in 46 (54,1%) specimens. We did not find statistical significance between frequency micro thrombosis of the LAA and morphology of the appendage (p = 0,3) with the trend to revealing more microthrombus in anatomic form of the LAA «chicken wing» (65% of this morphological type). Analysis of the diseases died patients showed absence AF in 54,3% cases of the LAA microthrombosis group. AF was diagnosed only in 16 (45,7%) cases in stroke group with revealed micro thrombosis in the LAA.

Conclusion. The investigation did not show statistical significance between the anatomical form of LAA and revealing of appendage microthrombosis. Possibly, there is a common pathomorphological process of the LAA thrombosis independence of the AF presence. Further trials are needed to confirm this consumption.

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