Preclinical Evaluation of an MR Conditional Forceps for MRI-Guided Endomyocardial Biopsy: A Multimodal Imaging Approach Using a Hybrid Vessel Phantom and Porcine In Vivo Models

Background MRI-guided cardiovascular procedures provide high-resolution, radiation-free imaging, but clinical translation is limited due to the lack of MR Conditional medical devices. This study presents a structured preclinical approach for validating MRI-guided devices and interventions, focusing on visibility and handling of a passively marked MR Conditional endomyocardial biopsy (EMB) forceps. Methods The EMB forceps was evaluated in a three-stage preclinical protocol. First, device visibility was assessed in a water-filled test box using fluoroscopy (Philips Allura Xper) and three MRI systems (Siemens MAGNETOM Skyra 3T, GE Signa HDxt 3.0T, and GE Signa HDxt 1.5T). Tissue samples from MR Conditional (n = 5) and standard Cordis biopsy forceps (n = 5) underwent histological analysis. Second, devices were assessed during fluoroscopy-guided EMB using a hybrid vessel phantom, with handling compared by experienced interventionists (n = 4). Next, MRI-guided testing of MR Conditional forceps was performed in the phantom (Siemens Biograph mMR 3.0T). Finally, in vivo testing was conducted in a porcine model (n = 4) using the same MRI system, following ethics committee approval. Results Visibility was confirmed in all three MRI systems (artifact coverage > 45% for EMB forceps head; >40% passive MR markers) and fluoroscopy. Handling was rated medium or higher by all operators. No significant difference in histological tissue quality and tissue sampling times (p > 0.05) was observed between MR Conditional and standard forceps. In vivo, five tissue samples of equivalent quality were successfully harvested (out of six attempts), with smaller artifact sizes compared to in vitro measurements. Conclusions The MR Conditional EMB forceps showed reliable visibility, handling, and accurate tissue sampling in both in vitro and in vivo testing. The developed in vitro testing protocol effectively evaluated key device characteristics, providing valuable insights in the early stages of in vivo trials.