In vivo cardiovascular catheterization under real-time MRI guidance

Purpose: To test the hypothesis that cardiac and coronary catheterization can be successfully performed under real-time MR guidance using a conventional x-ray angiographic catheter. Materials and Methods: Cardiac and coronary catheterization was conducted on eight farm pigs using a real-time True FISP sequence. A pigtail catheter was used for both left- and right-heart catheterizations performed on all eight animals, while an Amplatz or Judkins catheter was used for the right coronary catheterization that was attempted on five animals. The intravascular devices were visualized by means of their native susceptibility artifacts. For right coronary artery catheterizations, 25% diluted gadolinium (Gd) contrast material was injected to confirm engagement of the right coronary artery. Results: Cardiac catheterization of both the right- and left-heart chambers was successfully performed in all eight pigs. In addition, right coronary catheterization was successfully completed in four of the five pigs in which it was attempted. The procedure time for cardiac catheterization was one minute, while the time range required for coronary catheterization was 32-91 minutes. Conclusion: This work demonstrates that MRI-guided cardiac catheterization using conventional X-ray angiographic catheters is feasible; however, coronary catheterization with this passive-tracking technique is limited.