Article

Contrast-Enhanced Whole-Heart Coronary MRI with Bolus Infusion of Gadobenate Dimeglumine at 1.5 T.

Department of Medicine (Cardiovascular Division), Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA.
Magnetic Resonance Imaging (Impact Factor: 2.02). 02/2011; 66(2):392-398. DOI: 10.1002/mrm.22706
Source: PubMed

ABSTRACT We sought to investigate the T(1) kinetics of blood and myocardium after three infusion schemes of gadobenate dimeglumine (Gd-BOPTA) and subsequently compared contrast-enhanced whole-heart coronary MRI after a bolus Gd-BOPTA infusion with nonenhanced coronary MRI at 1.5T. Blood and myocardium T(1) was measured in seven healthy adults, after each underwent three Gd-BOPTA infusion schemes (bolus: 0.2 mmol/kg at 2 ml/sec, hybrid: 0.1 mmol/kg at 2 ml/sec followed by 0.1 mmol/kg at 0.1 ml/sec, and slow: 0.2 mmol/kg at 0.3 ml/sec). Fourteen additional subjects underwent contrast-enhanced coronary MRI with an inversion-recovery steady-state-free-precession sequence after bolus Gd-BOPTA infusion. Images were compared with nonenhanced T(2)-prepared SSFP whole-heart coronary MRI in signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), depicted vessel length, vessel sharpness, and subjective image quality. Bolus and slow infusion schemes resulted in similar T(1) during coronary MRI, whereas the hybrid infusion method yielded higher T(1) values. A bolus infusion of Gd-BOPTA significantly improved SNR, CNR, depicted coronary artery length, and subjective image quality when all segments were collectively compared but not when compared segment by segment. In conclusion, whole-heart SSFP coronary MRI at 1.5T can benefit from a bolus infusion of 0.2 mmol/kg Gd-BOPTA.

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