Magnetic resonance imaging-guided balloon angioplasty of coarctation of the aorta: a pilot study.
BACKGROUND
MRI guidance of percutaneous transluminal balloon angioplasty (PTA) of aortic coarctation (CoA) would be desirable for continuous visualization of anatomy and to eliminate x-ray exposure. The aim of this study was (1) to determine the suitability of MRI-controlled PTA using the iron oxide-based contrast medium Resovist (ferucarbotran) for catheter visualization and (2) to subsequently apply this technique in a pilot study with patients with CoA.


RESULTS
The MRI contrast-to-noise ratio and artifact behavior of Resovist-treated balloon catheters was optimized in in vitro and animal experiments (pigs). In 5 patients, anatomy of the CoA was evaluated before and after intervention with high-resolution respiratory-navigated 3D MRI and multiphase cine MRI. Position monitoring of Resovist-treated catheters was realized with interactive real-time MRI. Aortic pressures were continuously recorded. Conventional catheterization was performed before and after MRI to confirm interventional success. During MRI, catheters filled with 25 micromol of iron particles per milliliter of Resovist produced good signal contrast between catheters and their background anatomy but no image distortion due to susceptibility artifacts. All MRI procedures were performed successfully in the patient study. There was excellent agreement between the diameters of CoA and pressure gradients as measured during MRI and conventional catheterization. In 4 patients, PTA resulted in substantial widening of the CoA and a decrease in pressure gradients. In 1 patient, PTA was ineffective.


CONCLUSIONS
The MRI method described represents a potential alternative to conventional x-ray fluoroscopy for catheter-based treatment of patients with CoA.
Department of Congenital Heart Disease and Pediatric Cardiology, Deutsches Herzzentrum Berlin, Berlin, Germany.
Julia J
JJ
Krueger
Peter
P
Ewert
Sevim
S
Yilmaz
Dinah
D
Gelernter
Björn
B
Peters
Klaus
K
Pietzner
Axel
A
Bornstedt
Bernhard
B
Schnackenburg
Hashim
H
Abdul-Khaliq
Eckart
E
Fleck
Eike
E
Nagel
Felix
F
Berger
Titus
T
Kuehne
D000293:Adolescent; D000328:Adult; D015906:Angioplasty, Balloon, Coronary / Q000295:instrumentation / Q000379:methods*; D000818:Animals; D001017:Aortic Coarctation / Q000473:pathology / Q000628:therapy*; D002648:Child; D003287:Contrast Media; D003911:Dextrans; D052203:Ferrosoferric Oxide; D006801:Humans; D007501:Iron / Q000008:administration & dosage / Q000627:therapeutic use; D008279:Magnetic Resonance Imaging / Q000379:methods* / Q000592:standards; D058185:Magnetite Nanoparticles; D010087:Oxides / Q000008:administration & dosage / Q000627:therapeutic use; D010865:Pilot Projects; D012680:Sensitivity and Specificity; D013552:Swine
D003287:Contrast Media; D003911:Dextrans; D058185:Magnetite Nanoparticles; D010087:Oxides; D007501:Iron; C065507:ferumoxides; D052203:Ferrosoferric Oxide