Non-contrast-enhanced magnetic resonance angiography is equal to contrast-enhanced multislice computed tomography for correct aortic sizing before transcatheter aortic valve implantation

Background Correct sizing of the aortic annulus in aortic valve stenosis is crucial for successful transcatheter aortic valve implantation (TAVI). Multislice computed tomography (MSCT) seems to be most promising imaging modality for this pre-interventional diagnostic work-up, but has the disadvantage of exposing mostly co-morbid patients to iodine and nephrotoxic contrast agents. To establish a useful sizing method for TAVI without the use of contrast media, we compared measurements of a non-contrast magnetic resonance imaging (MRI) technique with MSCT serving as the reference standard.