Single-dose gadobutrol in comparison with single-dose gadobenate dimeglumine for magnetic resonance imaging of chronic myocardial infarction at 3 T

Abstract

Objectives: The aim of this study was to compare the contrast-to-noise ratio (CNR) values of infarct and remote myocardium as well as infarct and blood after application of 0.1 mmol/kg gadobutrol and 0.1 mmol/kg gadobenate dimeglumine on late gadolinium enhancement magnetic resonance (MR) images.

Material and methods: The study was a prospective randomized controlled clinical study. After informed consent was obtained, 20 patients (12 men, 8 women; mean age, 67 ± 11 years) with known chronic myocardial infarction were included for an intraindividual comparison of a single-dose gadobutrol and a single-dose gadobenate dimeglumine. Two MR imaging examinations were performed within a period of 28 days in a crossover design. Late gadolinium enhancement imaging was performed 10 minutes after gadolinium administration using a 2-dimensional phase-sensitive inversion recovery gradient echo sequence at 3 T. Infarct size, signal intensities (SIs), signal-to-noise ratio, and CNR were determined on phase-sensitive MR images. Values for CNR were calculated as CNRinfarct/myocardium = (SIinfarct - SImyocardium)/SDnoise and CNRinfarct/blood = (SIinfarct - SIblood)/SDnoise. In addition, the areas of myocardial infarction were determined on single slices. The entire infarct volumes were calculated by adding the areas with hyperenhancement multiplied by the slice thickness.

Results: Late gadolinium enhancement was present in all patients. Median values of the infarct area, infarct volume, and transmurality for gadobutrol and gadobenate dimeglumine showed good to excellent concordance (rc = 0.85, rc = 0.95, and rc = 0.71, respectively). The mean signal-to-noise ratio values for infarct, remote myocardium, and ventricular blood were 18.6 ± 6.5, 4.1 ± 3.7, and 14.6 ± 7.5, respectively, for gadobutrol and 18.8 ± 8.9, 4.9 ± 4.5, and 17.8 ± 10.1, respectively, for gadobenate dimeglumine (P = 0.93, P = 0.48, and P = 0.149, respectively). The mean values of CNRinfarct/myocardium and CNRinfarct/blood were 14.5 ± 5.9 and 4.0 ± 4.6, respectively, for gadobutrol and 13.9 ± 6.1 and 0.9 ± 4.5, respectively, for gadobenate dimeglumine (P = 0.69 and P = 0.02, respectively).

Conclusion: Both gadobutrol and gadobenate dimeglumine allow for successful late gadolinium enhancement imaging of chronic myocardial infarction after a single-dose application (0.1 mmol/kg) at 3 T. Gadobutrol provides a higher CNR between infarct and blood. The CNRs between infarct and normal myocardium, infarct size, and transmural extent were similar for both contrast agents.

FIGURE 1

Comparison of the infarct size on MR images, acquired after application gadobutrol and after application of gadobenate dimeglumine. A, The scatter diagram reveals the concordance of the infarct area determined on a selected plane. B, The Bland-Altman plot reveals the limits of agreement and percentage of the mean differences of the infarct areas determined on selected slices. C, The scatter diagram reveals the concordance of the entire infarct volume. D, The Bland-Altman plot reveals the limits of agreement and percentage of the mean differences of the infarct volumes. E, The scatter diagram reveals the concordance of the transmurality of the myocardial infarction. F, The Bland-Altman plot reveals the limits of agreement and the percentage of the mean differences of the transmural extent of the myocardial infarctions.

FIGURE 2

Overall evaluation of 20 patients. Bulls-eye plots show the number of segments affected by LGE according to the 17-segment American Heart Association model. The number, how often a certain segment is affected in the 20 patients, is encoded in gray colors indicated on the right. A, Bulls-eye plot of MR images acquired after application of gadobutrol. B, Bulls-eye plot of MR images acquired after application of gadobenate dimeglumine.

FIGURE 3

The box plots (horizontal lines by increasing order: minimum, 25%, 50% (median), 75% percentile, maximum) show the distribution of SNR and CNR values for gadobutrol and gadobenate dimeglumine. A, Median values of SNR for myocardial infarction (P = 0.93). B, Median values of SNR of normal myocardium (P = 0.48). C, Median values of SNR for left ventricular blood (P = 0.15). D, Median values of CNR_{infarct/myocardium} for myocardial infarction and normal myocardium (P = 0.67). E, Median values of CNR_{infarct/blood} for myocardial infarction and left ventricular blood (P = 0.02). *Statistically significant difference.

FIGURE 4

A 65-year-old male patient with myocardial infarction after occlusion of the right coronary artery and successful percutaneous coronary intervention 2 years ago: LGE MR images in short-axis orientation reveal a myocardial infarction in the inferior, inferoseptal, and inferolateral segments. The myocardial infarction reveals a nontransmural extent (arrowhead). A, MR image acquired after administration of 0.1 mmol/kg gadobutrol. B, MR image acquired after administration of 0.1 mmol/kg gadobenate dimeglumine. The nontransmural infarct scar shows a similar infarct area and transmural extent as well as affection of myocardial segments compared with panel A. The contrast between infarct and normal myocardium appears similar on both images; the contrast of infarct and left ventricular blood appears lower after application of gadobenate dimeglumine.

FIGURE 5

A 54-year-old male patient with myocardial infarction after occlusion of the left circumflex artery and successful bypass surgery 3 years ago: LGE MR images in short-axis orientation reveal a myocardial infarction in the lateral and inferolateral segments. The myocardial infarction reveals a nontransmural extent (arrowhead). A, MR image acquired after administration of 0.1 mmol/kg gadobutrol. B, MR image acquired after administration of 0.1 mmol/kg gadobenate dimeglumine. The nontransmural infarct scar shows a similar infarct area and transmural extent as well as affection of myocardial segments compared with panel A. The contrast between infarct and normal myocardium appears similar on both images; however, the contrast of infarct and left ventricular blood appears weak after application of gadobenate dimeglumine.

FIGURE 6

A 69-year-old female patient with myocardial infarction after occlusion of the left circumflex coronary artery and a high-grade stenosis in the right coronary artery: LGE MR images in short-axis orientation reveal a myocardial infarction in the lateral, inferoseptal, and inferior segments. The myocardial infarction reveals a nontransmural extent (arrowhead). A, MR image acquired after administration of 0.1 mmol/kg gadobutrol. B, MR image acquired after administration of 0.1 mmol/kg gadobenate dimeglumine. The nontransmural infarct scar shows a similar infarct area and transmural extent as well as affection of myocardial segments compared with panel A. The contrast between infarct and normal myocardium appears better after gadobutrol. The contrast of infarct and left ventricular blood appears weak after application of gadobenate dimeglumine.