Magnetic resonance imaging-guided catheter interventions in congenital heart disease.

Magnetic resonance imaging (MRI) has long been recognized as a useful technique for guiding diagnostic and therapeutic procedures. Biopsies have been guided by MRI since the 1980s1; neurosurgery followed soon thereafter.2 Excellent soft tissue contrast and accurate spatial localization and display in 3 dimensions were particular advantages of MRI over other modalities in neurological and body imaging. The application of MRI to cardiovascular interventions, however, has been much slower because of the technical challenges related mainly to cardiac motion. More recently, experimental work in animal models of acquired and congenital heart disease has demonstrated the feasibility of MRI-guided interventional cardiac catheterization.3–5 In 2003, Razavi et al6 published the first clinical experience with cardiac catheterization aided by MRI in 16 children and adults with congenital heart disease. In this issue of Circulation, Krueger and colleagues7 report on extending this concept to another clinical application: MRI-guided balloon angioplasty of aortic coarctation. Using commercially available catheters filled with a diluted solution of iron oxide particles, a homemade nonmetallic guidewire, and passive catheter tracking, the procedure was judged technically successful in all of the 5 patients in whom it was attempted.