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Background: Low-field (0.55T) magnetic resonance imaging (MRI) may allow MRI-guided interventions using available catheterization equipment, as radiofrequency-induced heating of interventional devices is reduced at low field., Objective: The purpose of this study was to test the feasibility of real-time MRI-guided right and left heart catheterization (R&LHC) as well as angioplasty and stenting of the inferior vena cava using a commercially available 0.55T MRI system (MAGNETOM Free.Max, Siemens Healthineers AG, Erlangen, Germany) with 80cm patient bore and maximum gradient amplitude and slew rate of 26 mT/m and 45 mT/m/ms, respectively. A secondary aim was to evaluate three different sizes of MR-visible markers., Method: Sheaths were placed in the femoral vein and artery of juvenile Yorkshire pigs under general anesthesia. Air-filled balloon wedge catheters and Judkins Right catheters were used for R&LHC, respectively, aided by an MR-compatible guidewire. Ferumoxytol was administered as a T1-shortening contrast agent and real-time visualization was carried out with a research interactive sequence using different spatiotemporal resolution settings. Inferior vena cava (IVC) angioplasty was performed using balloons filled with 1% gadolinium, and IVC stenting was performed with stainless steel stents and one platinum iridium covered stent., Result: RHC was successful in all 8 attempts with balloon tip visibility in all real-time protocols. One pig expired with ferumoxytol infusion, but the catheterization was completed post-mortem. LHC and IVC angioplasty were attempted and successful in 2 and 4 pigs, respectively. For stenting, higher resolution, lower frame rate imaging was used. All 6 attempted stent implantations were successful. The MR markers on the angioplasty balloon with widths of 0.5 and 1mm were more visible than the 0.25mm markers. Marker placement affected distinguishability from the crimped stent. Stainless steel stents created only minimal signal voids pre- and post-deployment; however, the platinum-iridium stent caused significant artifact obscuring wall apposition assessment., Conclusion: This study is the first to demonstrate the technical feasibility of R&LHC, IVC angioplasty, and IVC stenting using real-time MRI on a commercially available low field scanner., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Orlando Simonetti reports financial support was provided by Nano4Imaging. Orlando Simonetti reports financial support was provided by NuMed, Inc. Florian Maier reports a relationship with Siemens Healthineers AG that includes: equity or stocks. Aimee Armstrong reports a relationship with Medtronic Inc that includes: consulting or advisory. Ning Jin reports a relationship with Siemens Medical Solutions USA Inc that includes: employment. Jianing Pang reports a relationship with Siemens Medical Solutions USA Inc that includes: employment. Florian Maier reports a relationship with Siemens Healthcare GmbH that includes: employment. Axel Krafft reports a relationship with Siemens Healthcare GmbH that includes: employment. Orville Bramwell reports a relationship with Cook Advanced Technologies that includes: employment. Nathan Oom reports a relationship with Cook Advanced Technologies that includes: employment. Jesse Roll reports a relationship with Cook Advanced Technologies that includes: employment. Joshua Krieger reports a relationship with Cook Advanced Technologies that includes: employment. David Gross reports a relationship with MED Institute that includes: employment. Lucien de Mos reports a relationship with Nano4Imaging GmbH that includes: employment. Paul Borm reports a relationship with Nano4Imaging GmbH that includes: employment and equity or stocks. Orlando Simonetti reports a relationship with Siemens Healthineers AG that includes: funding grants. Orlando Simonetti reports a relationship with Cook Medical Inc that includes: funding grants. Orlando Simonetti reports a relationship with Nano4Imaging that includes: funding grants. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025. Published by Elsevier Inc.)