title: MR-trackable intramyocardial injection catheter.
abstract: There is growing interest in delivering cellular agents to infarcted myocardium to prevent postinfarction left ventricular remodeling. MRI can be effectively used to differentiate infarcted from healthy myocardium. MR-guided delivery of cellular agents/therapeutics is appealing because the therapeutics can be precisely targeted to the desired location within the infarct. In this study, a steerable intramyocardial injection catheter that can be actively tracked under MRI was developed and tested. The components of the catheter were arranged to form a loopless RF antenna receiver coil that enabled active tracking. Feasibility studies were performed in canine and porcine myocardial infarction models. Myocardial delayed-enhancement (MDE) imaging identified the infarcted myocardium, and real-time MRI was used to guide left ventricular catheterization from a carotid artery approach. The distal 35 cm of the catheter was seen under MRI with a bright signal at the distal tip of the catheter. The catheter was steered into position, the distal tip was apposed against the infarct, the needle was advanced, and a bolus of MR contrast agent and tissue marker dye was injected intramyocardially, as confirmed by imaging and postmortem histology. A pilot study involving intramyocardial delivery of magnetically labeled stem cells demonstrated the utility of the active injection catheter system.
authors.affiliation: Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21025, USA. pkarmar@mri.jhu.edu
authors.forename: P V
authors.initials: PV
authors.lastname: Karmarkar
authors.forename: D L
authors.initials: DL
authors.lastname: Kraitchman
authors.forename: I
authors.initials: I
authors.lastname: Izbudak
authors.forename: L V
authors.initials: LV
authors.lastname: Hofmann
authors.forename: L C
authors.initials: LC
authors.lastname: Amado
authors.forename: D
authors.initials: D
authors.lastname: Fritzges
authors.forename: R
authors.initials: R
authors.lastname: Young
authors.forename: M
authors.initials: M
authors.lastname: Pittenger
authors.forename: J W M
authors.initials: JW
authors.lastname: Bulte
authors.forename: E
authors.initials: E
authors.lastname: Atalar
mesh_terms: D000818:Animals; D006328:Cardiac Catheterization / Q000295:instrumentation; D002404:Catheterization; D003287:Contrast Media; D003911:Dextrans; D004285:Dogs; D004867:Equipment Design; D052203:Ferrosoferric Oxide; D015552:Injections, Intralesional; D007501:Iron; D008279:Magnetic Resonance Imaging; D058185:Magnetite Nanoparticles; D045164:Mesenchymal Stem Cell Transplantation; D009203:Myocardial Infarction / Q000473:pathology / Q000628:therapy*; D009206:Myocardium / Q000473:pathology; D010087:Oxides; D019047:Phantoms, Imaging; D013552:Swine
chemical_list: D003287:Contrast Media; D003911:Dextrans; D058185:Magnetite Nanoparticles; D010087:Oxides; D007501:Iron; C065507:ferumoxides; D052203:Ferrosoferric Oxide