Incidence and factors influencing left atrial clot in patients with mitral stenosis and normal sinus rhythm.

M itral stenosis (MS) is a common finding in rheumatic heart disease and can lead to enlargement of the left atrium and stasis of blood in this heart chamber. This can lead to an increased risk of clot formation in the left atrium and the left atrial appendage. In numerous studies to date, various precipitating factors for the formation of a clot inside the left atrium have been identified, including atrial fibrillation (AF) rhythm, left atrial size, duration of symptoms, advanced age, and severity of MS. Furthermore, mitral regurgitation (MR) in conjunction with MS has been mentioned as a factor which reduces the risk of left atrial clot formation. This study was performed to determine the incidence of left atrial clot in a group of patients who remained in normal sinus rhythm (NSR) and to establish the factors which play a determining role in this process.