Left Atrial Appendage Neck Modeling for Closure Surgery.

The left atrial appendage closure surgery is the main treatment of thrombosis in patients with atrial fibrillation. Left atrial appendage neck is the region of implanting occluder in the surgery. The occluder is strictly matched with the neck to prevent the occluder piercing the endocardium or falling off and avoid threatening patients' lives. So we build a model of left atrial appendage neck based on the segmentation result of maximal volume phase from CT data. The model automatically generated by our approach is a circumscribed cylinder to represent the irregular columnar neck. This circumscribed cylinder can help to determine the diameter of the closure device before the surgery, the implanted position and pose of the device during the surgery. Specifically, we successfully solved these problems including the auto-detection of the boundary points of left atrial appendage ostium, the establishment of the standard coordinate system, the auto-calculation of the cylinder height and the polychromatic display of occlusive tension on the neck. We built our model on 100 patients' data and dissected the three pig hearts to do comparative experiments. Tests were performed in 67 occlusion surgeries with the success rate of 97.01%. These indicate that our approach can precisely and non-invasively model the left atrial appendage neck for assisting closure surgeries.