Interventional CMR: Clinical applications and future directions

Abstract

Interventional cardiovascular magnetic resonance (iCMR) promises to enable radiation-free catheterization procedures and to enhance contemporary image guidance for structural heart and electrophysiological interventions. However, clinical translation of exciting pre-clinical interventions has been limited by availability of devices that are safe to use in the magnetic resonance (MR) environment. We discuss challenges and solutions for clinical translation, including MR-conditional and MR-safe device design, and how to configure an interventional suite. We review the recent advances that have already enabled diagnostic MR right heart catheterization and simple electrophysiologic ablation to be performed in humans and explore future clinical applications.

Fig. 1

Clinical X-ray fused with MRI (XFM)-guided closure of ventricular-atrial (Gerbode) defect. a Four-chamber cine MRI showing defect between left ventricle and right atrium (arrow). Left-to-right flow is clearly seen. b XFM image in which the defect appears as a red overlay on the fluoroscopy (arrow). c Nitinol closure device on its delivery cable positioned across the defect. Both discs have been deployed. d Closure device after release. (Courtesy of Kanishka Ratnayaka (2014), Department of Cardiology, Children’s National Hospital Center, Washington DC, USA)

Fig. 2

Clinical MRI right heart catheterization. The gadolinium-filled balloon at the tip of the catheter is visible as a white ball (arrows) in the inferior vena cava (a), superior vena cava (b), right ventricle (c), and right pulmonary artery (d)

Fig. 3

Clinical MR-guided electroanatomic mapping and ablation. a Real-time MR imaging of the electroanatomic mapping and ablation catheter. The passively tracked tip (arrow) is positioned above the cavo-tricuspid isthmus. Post-ablation T2-weighted (b) and late gadolinium enhancement (c) images of the cavo-tricuspid isthmus showing the ablation lesion (arrows). AA ascending aorta, MV mitral valve, RA right atrium, RV right ventricle. (Courtesy of M. Gutberlet, M. Grothoff and G. Hindricks (2014), University of Leipzig, Germany)