Magnetic resonance imaging of targeted catheter-based implantation of myogenic precursor cells into infarcted left ventricular myocardium.
OBJECTIVE
This study was designed to test the hypothesis that myocardial implantation of myogenic precursor cells (MPC) loaded with iron oxide can be reliably detected in vivo by cardiac magnetic resonance imaging (MRI).


BACKGROUND
In vivo imaging of targeted catheter-based implantation of MPC into infarcted left ventricular (LV) myocardium is unavailable.


METHODS
The study was conducted in seven farm pigs (four with anterior myocardial infarction), in which autologous MPC were injected through a percutaneous catheter allowing for LV electromechanical mapping and guided micro-injections into normal and infarcted myocardium. Cardiac MRI was used to detect implanted MPC previously loaded with iron oxide nanoparticles.


RESULTS
Magnetic resonance imaging data were compared with LV electromechanical mapping and cross-registered pathology. All 9 injections into normal and 12 injections into locally damaged myocardium were detected on T2-weighted spin echo and inversion-recovery true-fisp MRI (low signal areas) with good anatomical concordance with sites of implantation on electromechanical maps. All sites of injection were confirmed on pathology that showed in all infarct animals iron-loaded MPC at the center and periphery of the infarct as expected from MRI.


CONCLUSIONS
Targeted catheter-based implantation of iron-loaded MPC into locally infarcted LV myocardium is accurate and can be reliably demonstrated in vivo by cardiac MRI. The ability to identify noninvasively intramyocardial cell implantation may be determinant for future experimental studies designed to analyze subsequent effects of such therapy on detailed segmental LV function.
Garot
Jérôme
J
INSERM U 400, Fédération de Cardiologie, Henri Mondor University Hospital, AP-HP, 51 Avenue du Maréchal de Lattre de Tassigny, 94010 Créteil, France. jgarot@free.fr
Unterseeh
Thierry
T
Teiger
Emmanuel
E
Champagne
Stéphane
S
Chazaud
Bénédicte
B
Gherardi
Romain
R
Hittinger
Luc
L
Guéret
Pascal
P
Rahmouni
Alain
A
D000818:Animals; D002404:Catheterization; D017690:Cell Transplantation; D002478:Cells, Cultured; D003287:Contrast Media; D003911:Dextrans; D052203:Ferrosoferric Oxide; D006352:Heart Ventricles / Q000473:pathology; D007501:Iron; D008279:Magnetic Resonance Imaging; D058185:Magnetite Nanoparticles; D008845:Microinjections; D018482:Muscle, Skeletal / Q000637:transplantation*; D009203:Myocardial Infarction / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D010087:Oxides; D033581:Stem Cell Transplantation; D013552:Swine; D016277:Ventricular Function, Left
D003287:Contrast Media; D003911:Dextrans; D058185:Magnetite Nanoparticles; D010087:Oxides; D007501:Iron; C065507:ferumoxides; D052203:Ferrosoferric Oxide