Right heart catheterization using real-time MR imaging to navigate a gadolinium-filled balloon (arrows) between cardiac chambers. Standard real-time bSSFP (A, C, E) and real-time bSSFP with saturation prepulses (B, D, F) are depicted. Saturation prepulses are used to isolate the gadolinium-filled balloon signal. (From Ratnayaka K, Faranesh AZ, Hansen MS, et al. Real-time MRI-guided right heart catheterization in adults using passive catheters. Eur Heart J 2013;34(5):380–9; with permission.)