Contrast-enhanced MR imaging of coronary arteries: comparison of intra- and extravascular contrast agents in swine.
OBJECTIVE
To compare the efficacy of an intravascular contrast agent, gadomer-17, in improving magnetic resonance (MR) imaging of coronary arteries with that of an extravascular agent, gadopentetate dimeglumine, in pigs.


METHODS
Eight pigs underwent imaging after three injections: 0.20 mmol of gadopentetate dimeglumine per kilogram of body weight and 0.05 and 0.10 mmol/kg gadomer-17. Coronary images were acquired repeatedly after each injection by using an inversion-recovery-prepared segmented three-dimensional sequence with either breath holding (n = 4) or respiratory gating (n = 4). Coronary artery-to-myocardium contrast-to-noise ratios (CNRs) were compared between injections.


RESULTS
At breath-hold imaging, substantial CNR improvement over precontrast images was observed in images acquired during the first pass of gadopentetate dimeglumine in coronary arteries and up to 6 and 10 minutes after 0.05 and 0.10 mmol/kg of gadomer-17 injections, respectively. The CNR with 0.10 mmol/kg of gadomer-17 was 20% (P <.05) higher than that with gadopentetate dimeglumine at first-pass imaging. At respiratory-gated imaging, significant CNR improvement (P <.05) over precontrast images was observed in images acquired up to 10, 30, and 50 minutes after gadopentetate dimeglumine and both gadomer-17 injections, respectively. The CNR on the first images obtained after 0.10 mmol/kg gadomer-17 injection was 168% (P <.05) higher than that on the images obtained after gadopentetate dimeglumine injection.


CONCLUSIONS
Gadomer-17 provided greater and more persistent CNR improvements than did gadopentetate dimeglumine; further evaluation of its utility for coronary imaging in humans is warranted.
Department of Radiology, Northwestern University Medical School, 448 E Ontario St, Ste 700, Chicago, IL 60611, USA. d-li2@northwestern.edu
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Li
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Zheng
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Weinmann
D000818:Animals; D003287:Contrast Media / Q000008:administration & dosage; D003331:Coronary Vessels / Q000033:anatomy & histology*; D005682:Gadolinium; D019786:Gadolinium DTPA / Q000008:administration & dosage; D007089:Image Enhancement / Q000379:methods; D018810:Magnetic Resonance Angiography / Q000379:methods*; D013552:Swine
D003287:Contrast Media; C402765:gadomer 17; D005682:Gadolinium; D019786:Gadolinium DTPA