Integrating Imaging Modalities
Transcatheter interventions for congenital heart disease can be challenging and require not only the understanding of anatomy but a working knowledge of modern imaging modalities. Fluoroscopy has poor characterization of non-radiopaque structures and has limitations in providing three-dimensional (3D) spatial information. Similarly, echocardiography by itself has limitations in detecting the position of the catheters and wires. Additionally, the orientation of the images from various imaging modalities can be different which poses an added challenge to the operator. A real-time integration of the imaging modalities with 3D information and live fluoroscopy provides a rapid recognition and orientation of the cardiac structures during percutaneous interventions. It can also improve the communication between various members for the team while performing the procedure.
Cardiac computer tomography angiography—virtual planning. Virtual devices (white arrows) are placed at the position of the ventricular septal defect to make decisions on the size and shape. Additionally, the interaction with surrounding structures can be examined (MP4 59345 kb)
CTA-fluoroscopy fusion—crossing ventricular septal defect. Fusion of the CTA with live fluoroscopy shows a 3D model of the heart overlaid over the fluoroscopy during the procedure for guidance. Segmentation of the heart is visible, but it is dimmed to avoid blocking the view of the wires. A circular marker at the position of the ventricular septal defect (VSD) helps the operator in steering the guidewire. The guidewire (small white arrows) is seen crossing the ventricular septal defect (VSD) retrograde from the aorta. The guidewire is inserted into the right ventricle through the VSD (large white arrow) (MP4 59628 kb)
CTA-fluoroscopy fusion—creating arterial-venous (AV) rail. An AV rail is created to support the delivery of device. The left ventricle is seen in blue, aorta in orange, and pulmonary arterial system in red color. The retrograde guidewire (white arrows) crossing the VSD is advanced and positioned in the left pulmonary artery. Then, a 6F JR4 guide catheter with an 18 × 30 mm Ensnare system (black arrows) is advanced through the right internal jugular vein. The retrograde guidewire is snared and externalized creating an AV rail (MP4 153400 kb)