Improved coronary artery definition with T2-weighted, free-breathing, three-dimensional coronary MRA

Background-Three-dimensional (3D) navigator-gated and prospectively correct ed free-breathing coronary magnetic resonance angiography (MRA) allows for submillimeter image resolution but suffers from poor contrast between coron ary blood and myocardium. Data collected over >100 ms/heart beat are also s usceptible to bulk cardiac and respiratory motion. To address these problem s, we examined the effect of a T2 preparation prepulse (T2prep) for myocard ial suppression and a shortened acquisition window on coronary definition. Methods and Results-Eight healthy adult subjects and 5 patients with confir med coronary artery disease (CAD) underwent free-breathing 3D MRA with and without T2prep and with 120- and 60-ms data-acquisition windows. The T2prep resulted in a 123% (P < 0.001) increase in contrast-to-noise ratio (CNR), Coronary edge definition was improved by 33% (P < 0.001). Acquisition windo w shortening from 120 to 60 ms resulted in better vessel definition (11%; P < 0.001), Among patients with CAD, there was a good correspondence with di sease. Conclusions-Free-breathing, T2prep, 3D coronary MRA with a shorter acquisit ion window resulted in improved CNR and better coronary artery definition, allowing the assessment of coronary disease. This approach offers the poten tial for free-breathing, noninvasive assessment of the major coronary arter ies.