Real-time magnetic resonance imaging-guided endovascular recanalization of chronic total arterial occlusion in a swine model.
BACKGROUND
Endovascular recanalization (guidewire traversal) of peripheral artery chronic total occlusion (CTO) can be challenging. X-ray angiography resolves CTO poorly. Virtually "blind" device advancement during x-ray-guided interventions can lead to procedure failure, perforation, and hemorrhage. Alternatively, MRI may delineate the artery within the occluded segment to enhance procedural safety and success. We hypothesized that real-time MRI (rtMRI)-guided CTO recanalization can be accomplished in an animal model.


RESULTS
Carotid artery CTO was created by balloon injury in 19 lipid-overfed swine. After 6 to 8 weeks, 2 underwent direct necropsy analysis for histology, 3 underwent primary x-ray-guided CTO recanalization attempts, and the remaining 14 underwent rtMRI-guided recanalization attempts in a 1.5-T interventional MRI system. Real-time MRI intervention used custom CTO catheters and guidewires that incorporated MRI receiver antennae to enhance device visibility. The mean length of the occluded segments was 13.3+/-1.6 cm. The rtMRI-guided CTO recanalization was successful in 11 of 14 swine and in only 1 of 3 swine with the use of x-ray alone. After unsuccessful rtMRI (n=3), x-ray-guided attempts were also unsuccessful.


CONCLUSIONS
Recanalization of long CTO is entirely feasible with the use of rtMRI guidance. Low-profile clinical-grade devices will be required to translate this experience to humans.
Raval
Amish N
AN
Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892-1538, USA.
Karmarkar
Parag V
PV
Guttman
Michael A
MA
Ozturk
Cengizhan
C
Sampath
Smita
S
DeSilva
Ranil
R
Aviles
Ronnier J
RJ
Xu
Minnan
M
Wright
Victor J
VJ
Schenke
William H
WH
Kocaturk
Ozgur
O
Dick
Alexander J
AJ
Raman
Venkatesh K
VK
Atalar
Ergin
E
McVeigh
Elliot R
ER
Lederman
Robert J
RJ
D017130:Angioplasty / Q000295:instrumentation / Q000379:methods; D000818:Animals; D001157:Arterial Occlusive Diseases / Q000473:pathology / Q000628:therapy*; D002340:Carotid Artery Diseases / Q000473:pathology / Q000628:therapy; D002404:Catheterization / Q000295:instrumentation / Q000379:methods*; D002908:Chronic Disease; D004195:Disease Models, Animal; D004867:Equipment Design; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods; D016491:Peripheral Vascular Diseases / Q000473:pathology / Q000628:therapy; D013552:Swine; D016896:Treatment Outcome