Human Cardiac Magnetic Resonance at Ultrahigh Fields: Technical Innovations, Early Clinical Applications and Opportunities for Discoveries

Abstract The objective of this chapter is to document advances and to review progress in cardiac magnetic resonance (MR) at ultra-high fields (UHFs; B 0 ≥ 7 T) with the goal to attract talent, clinical adopters, collaborations, and resources to the biomedical and diagnostic imaging communities. This chapter surveys traits, advantages, and challenges of cardiac MR at 7 T. The considerations cover technical advances including enabling radiofrequency (RF) antenna technology, multichannel transmit systems, and ancillary hardware. Key concepts, emerging technologies, practical considerations, frontier applications including X-nuclei imaging, and future directions of UHF cardiac MR are provided. RF safety of cardiac MR at 7 T including RF-induced heating of passive conductive devices is discussed. Examples of UHF cardiac imaging strategies are demonstrated. Their added value over the kindred counterparts at lower fields is explored along with an outline of research promises. The achievements of cardiac UHF-MR are powerful motivators and enablers, since extra speed, signal, and imaging capabilities may be invested to overcome the fundamental constraints that continue to hamper traditional cardiac MR applications. If practical obstacles, concomitant physics effects, and technical impediments can be overcome in equal measure, sophisticated cardiac UHF-MR will help to open the door to new MR imaging (MRI) and MR spectroscopy (MRS) approaches for basic research and clinical science, with the lessons learned at 7 T being transferred into broad clinical use including diagnostics and therapy guiding at lower fields.