Assessment of left atrial function using multi-slice CT images

The function of left atrium can be accurately estimated non-invasively using 4D CT cardiac images. A self-developed image analysis program will first reconstruct 3D volume of heart. Then, one may re-sample images for accurately deleting the 4 pulmonary veins from the atrium and set the boundary. With the prior processed information, the active contour methodology and seed regional growth methodology were implemented to delineate the atrial contour. With a calibration standard of 500 ml saline with contrast medium in bag, both methods were able to estimate volume within 5% of error. Thirty sets of patientpsilas CT cardiac images that were acquired at 30% and 90% of RR interval. The dimension of pulmonary veins and the left atrial volume was evaluated. The contractility of pulmonary vein and the ejection fraction (EF) of atrium was calculated. The result shows that the left atrium with a larger volume will have a poor ejection fraction.