Association of Structure and Function of left atrial Appendage with Left atrial appendage Thrombus formation in patients with Rheumatic Heart Disease: ASFALT-RHD study

Abstract

Context: In patients with rheumatic heart disease (RHD), left atrial appendage (LAA) dilation and thrombus formation is widely known. LAA thrombus formation is a risk factor for stroke even in patients with sinus rhythm. The aim of this study was to determine an association between LAA structure and function with respect to thrombus formation and differences in LAA size and velocity between patients with sinus rhythm and those with atrial fibrillation (AF). Materials and Methods: We prospectively studied LAA structure and function in 120 patients with RHD by transthoracic echocardiography and/or transesophageal echocardiography by measuring left atrial (LA) dimension, LA area, LAAmax/min, LAA ejection fraction (EF), and LAA emptying velocity. Results: Four out of 48 patients with sinus rhythm had LAA thrombus. In 72 patients with AF, 32 had LAA thrombus. Patients with LAA thrombus had lower mean LAA EF and emptying velocity both variables P-value is same (P<0.0001 and P<0.0001) Patients with LAA thrombus had increased mean LAA max and LAA min as compared to LAA max and LAA min in patients without LAA thrombus (P 0.008 for mean LAA max and P<0.0001 for LAA min respectively). Patients with AF with LAA thrombus had greater LAAmax compared to that in patients with AF without LAA thrombus (P < 0.0001). Doppler demonstrated a recognizable sawtooth LAA outflow velocity pattern in 32 of 36 (88.9%) patients with LAA thrombus versus 32 of 84 (38.1%) patients without LAA thrombus. Conclusions: We conclude that LAA contractility is reduced in RHD with LAA thrombus, and loss of both contractility and LAA dilation is associated with increased risk of thrombus formation and hence the risk of stroke.

Keywords

• atrial fibrillation
• left atrial appendage
• rheumatic heart disease