MR-guided aortic valvuloplasty. A real-time steady-state free precession MR-sequence was used for monitoring of the intervention. Panel A. A MR-compatible pacemaker lead (arrows) was placed in the right ventriclar apex of the heart under MR-guidance before the valvuloplasty. Panel B. A Cobra-catheter with a passive MR-compatible guidewire (arrows) was positioned in the aorta ascendens. Panel C. The catheter and the guidewire (arrows) were then placed in the left ventricle. Panel D. After the pacing rate of approximately 180 bpm the balloon was inflated with diluted 5% Resovist to perform valvuloplasty.