MRI-guidance of invasive cardiovascular procedures has been limited by the unavailability of safe devices. Most cardiovascular procedures require long conductive devices (eg. guidewires and catheters) that are susceptible to RF-induced heating. Because heating is related quadratically to field strength, we propose to reduce the MRI field strength to 0.55T. Using a custom high-performance 0.55T MRI system, we performed MRI-guided catheterizations on patients with commercial metallic guidewires using standard high flip angle bSSSP real-time imaging to produce good image quality and contrast without RF-induced heating. Low field MRI combined with high-performance hardware will be fundamentally enabling for MRI guidance of invasive procedures.