Breath-hold coronary MR angiography with volume-targeted imaging

To illustrate a new concept for fast coronary artery screening with breath-hold volume targeted magnetic resonance (MR) imaging.

Ten volunteers and 25 patients were imaged at a field strength of 1.5 T with an MR system with phased-array-coil reception and capable of echo-planar imaging. End-expiration breath-hold volume localization of the entire heart was performed with three-dimensional (3D) multishot segmented echo-planar imaging in 16-22 heartbeats. Interaction with a multiplaner reformation platform provided the optimal double-oblique volumes necessary to target seven coronary artery segments. Each segment was evaluated with 24-mm-thick volumes and breath holds at end expiration and magnetization transfer-enhanced 3D turbo fast low-angle shot imaging in 21 heartbeats. An intravascular contrast agent was used in eight patients to improve blood-myocardium contrast for the heart volume localizer acquisitions.

The entire coronary tree was consistently covered in fewer than 13 breath holds. The scheme was successful in all volunteers and in 22 patients who could achieve adequate breath hold. With end-expiration acquisitions, the prescribed 24-mm-thick volumes were reproducible for all coronary segments in all cooperative subjects.

Despite its status as the indisputable standard of reference for the detection of coronary artery disease, conventional coronary angiography remains costly and highly invasive, with associated risks of major complications, including stroke and death. Breath-hold volume targeted acquisitions permit rapid localization and coverage of the entire coronary tree with adequate resolution for evaluating the coronary arteries.