Abstract 15003: Enhancing Intracardiac Ultrasound Imaging of the Left Atrial Appendage
INTRODUCTION: Assessment of the left atrial appendage (LAA) is important for detecting thrombus, deploying occlusion devices, and ablating LAA foci. Intracardiac echocardiography (ICE) imaging of the LAA is limited from the right atrium (RA). We hypothesized that more complete imaging could be obtained by combining images from the septal aspect of the right ventricular inflow tract (RVIT) and the coronary sinus (CS) or its os.
METHODS: In 31 patients (20 males, mean age 58±11 years) undergoing ablation for atrial fibrillation ICE images were obtained via catheter (Biosense Webster) in conjunction with an electroanatomical mapping (EAM) system (Biosense Webster). LAA contours were created from ICE images obtained from the RA, RVIT, and the CS. Figure 1 right panel shows a representative contour (green) of the LAA as viewed from the CS. The left panel shows color-coded LAA contours from individual viewpoints. Individual LAA volumes and total LAA volume were calculated with the EAM system by 3D reconstruction.
RESULTS: The LAA was visualized in all patients. The LAA was poorly visualized from the RA in 5 patients and from the CS in 5 patients. The mean reconstructed LAA volume using all 3 imaging viewpoints was 11.83±6.58mL. The mean visualized LAA volumes from each imaging site were RA 3.54±5.43mL, RVIT 8.0±5.75mL, and CS 3.61±2.95mL, respectively accounting for an average of 26.2±23.3%, 65.5±21.9%, and 33.4±23.4% of the total LAA reconstructed volume.
CONCLUSIONS: Combined use of images from three anatomic locations that can be reached from the RA markedly improves ICE imaging for more complete evaluation of the left atrial appendage.
- © 2012 by American Heart Association, Inc.