Improved three-dimensional free-breathing coronary magnetic resonance angiography using gadocoletic acid (B-22956) for intravascular contrast enhancement.
OBJECTIVE
To evaluate gadocoletic acid (B-22956), a gadolinium-based paramagnetic blood pool agent, for contrast-enhanced coronary magnetic resonance angiography (MRA) in a Phase I clinical trial, and to compare the findings with those obtained using a standard noncontrast T2 preparation sequence.


METHODS
The left coronary system was imaged in 12 healthy volunteers before B-22956 application and 5 (N = 11) and 45 (N = 7) minutes after application of 0.075 mmol/kg of body weight (BW) of B-22956. Additionally, imaging of the right coronary system was performed 23 minutes after B-22956 application (N = 6). A three-dimensional gradient echo sequence with T2 preparation (precontrast) or inversion recovery (IR) pulse (postcontrast) with real-time navigator correction was used. Assessment of the left and right coronary systems was performed qualitatively (a 4-point visual score for image quality) and quantitatively in terms of signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), vessel sharpness, visible vessel length, maximal luminal diameter, and the number of visible side branches.


RESULTS
Significant (P < 0.01) increases in SNR (+42%) and CNR (+86%) were noted five minutes after B-22956 application, compared to precontrast T2 preparation values. A significant increase in CNR (+40%, P < 0.05) was also noted 45 minutes postcontrast. Vessels (left anterior descending artery (LAD), left coronary circumflex (LCx), and right coronary artery (RCA)) were also significantly (P < 0.05) sharper on postcontrast images. Significant increases in vessel length were noted for the LAD (P < 0.05) and LCx and RCA (both P < 0.01), while significantly more side branches were noted for the LAD and RCA (both P < 0.05) when compared to precontrast T2 preparation values.


CONCLUSIONS
The use of the intravascular contrast agent B-22956 substantially improves both objective and subjective parameters of image quality on high-resolution three-dimensional coronary MRA. The increase in SNR, CNR, and vessel sharpness minimizes current limitations of coronary artery visualization with high-resolution coronary MRA.
Paetsch
Ingo
I
Clinic of Internal Medicine/Cardiology, German Heart Institute-Berlin, Augustenburger Platz 1, 13353 Berlin, Germany. paetsch@dhzb.de
Huber
Michael E
ME
Bornstedt
Axel
A
Schnackenburg
Bernhard
B
Boesiger
Peter
P
Stuber
Matthias
M
Fleck
Eckart
E
Cavagna
Friedrich
F
Nagel
Eike
E
D000328:Adult; D003287:Contrast Media; D003331:Coronary Vessels / Q000033:anatomy & histology*; D005682:Gadolinium; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D001239:Inhalation / Q000502:physiology; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D009942:Organometallic Compounds
C440468:B-22956-1; D003287:Contrast Media; D009942:Organometallic Compounds; D005682:Gadolinium