Intraindividual comparison of gadobutrol and gadopentetate dimeglumine for detection of myocardial late enhancement in cardiac MRI

OBJECTIVE. Gadobutrol is an extracellular macrocyclic gadolinium chelate recently introduced in MRI, and it has already been used for cardiac late enhancement imaging; however, until now it has never been compared with gadopentetate dimeglumine. The purpose of our study was to compare 0.1 mmol/kg gadobutrol to 0.2 mmol/kg gadopentetate dimeglumine for the detection of myocardial late enhancement in the same group of patients. SUBJECTS AND METHODS. This was an exploratory single-blind parallel group study comparing gadobutrol (0.1 mmol/kg) to gadopentetate dimeglumine (0.2 mmol/kg) in 20 adult patients scheduled for cardiac late enhancement MRI with gadopentetate dimeglumine and whose MR images showed late enhancement. MR images were acquired at 10, 15, and 20 minutes after peripheral injection of gadobutrol by using a 3D turbo field echo inversion recovery T1-weighted sequence. Volume and percentage of late enhancement, number of involved segments, late enhancement localization and pattern, and late enhancement signal-tonoise ratio (SNR) and contrast-to-noise ratio (CNR) were compared between contrast agents. RESULTS. Late enhancement was not significantly different with gadobutrol and gadopentetate dimeglumine both in terms of total volume of myocardium (mean ± SD, 37.8 ± 56.1 and 35.1 ± 46.7 cm ³, respectively; p = 0.33) and percentage of myocardial wall involvement (22.5% ± 19.1% and 22.0% ± 17.2%, respectively; p = 0.67). The number of segments involved was not different (138 with gadobutrol vs 134 with gadopentetate dimeglumine). Furthermore, SNR and CNR were not different (gadopentetate dimeglumine, 123.8 ± 82.9 and gadobutrol, 117.2 ± 88.6, p = 0.58 and gadopentetate dimeglumine, 96.2 ± 68.9 and gadobutrol, 88.4 ± 72.9, p = 0.53, respectively). CONCLUSION. A single dose of gadobutrol seems to be as effective as a double dose of gadopentetate dimeglumine for the detection of late enhancement.