Prevalence and Echocardiographic Predictors of Left Atrial Appendage Inactivity in Patients of Mitral Stenosis

ABSTRACT

Background: Mitral stenosis (MS) is a common valvular heart disease. Thromboembolism is one of the most serious consequences of mitral stenosis, particularly when it is accompanied with atrial fibrillation (AF). When linked with Left atrial appendage inactivity (LAAI), patients with sinus rhythm (SR) are also at risk for this condition. In mitral stenosis, LAA inactivity determined by S-wave is an independent predictor of thromboembolism. The aim of the study was to evaluate the Prevalence and Echocardiographic Predictors of Left Atrial Appendage inactivity in patients of Mitral Stenosis.Material & Methods:Sixty MS patients were evaluated by transthoracic echocardiography (TTE) and all patients underwent transesophageal echocardiography (TEE). The annular systolic (S-wave) and diastolic (Em- and Am-waves) velocities were recorded by tissue Doppler imaging (TDI). LAA inactivity was defined as LAA emptying velocity <25 cm/second determined by pulse wave Doppler at the junction of LA & LAA (TEE). Patients were divided into three groups; group A I (n = 18). Sinus rhythm (SR) and LAA emptying velocity ?25 cm/sec, group A II (n -22) SR and LAA emptying velocity <25cm/sec and group B (n = 20) atrial fibrillation.Results:Thrombus was detected in 14 patients and spontaneous echo contrast (SEC) was detected in 43 patients. Both S-wave and peak LAA emptying velocities were decreasing, while SEC frequency and density were increasing from group A to group B. There was a positive correlation between LAA emptying vs. S-wave and LAA emptying vs. Am velocities (p < 0.001, r= 0.708 and p<0.001, r=0.495). Multivariate regression analysis showed that only S-wave is the independent predictor of inactive LAA (p = 0.001, odds ratio = 0.133, 95% Cl =0.032-0.556). In patients with SR, the cutoff value of S-wave was 10 cm/sec for the prediction of the presence of inactive LAA (sensitivity 92.3%, specificity 95.3%).Conclusions:In individuals with severe mitral stenosis in sinus rhythm, there is a significant prevalence of left atrial appendage inactivity. The mean pressure gradient across the mitral valve, as well as S-wave are independent predictors of left atrial appendage inactivity. Inactivity of the left atrial appendage is an independent predictor of left atrial/left atrial appendage smoke and associated thrombus.