The protein binding substance ibuprofen does not affect the T1 time or partition coefficient in contrast-enhanced cardiovascular magnetic resonance.
BACKGROUND
Contrast enhanced cardiovascular magnetic resonance (CMR) with T1 mapping enables quantification of diffuse myocardial fibrosis. Various factors, however, can interfere with T1 measurements. The purpose of the current study was to assess the effect of co-medication with a typical protein binding drug (ibuprofen) on T1 values in vitro and in vivo.


METHODS
50 vials were prepared with different concentrations of gadobenate dimeglumine, ibuprofen and human serum albumin in physiologic NaCl solution and imaged at 1.5T with a spin echo sequence at multiple TRs to measure T1 values and calculate relaxivities. 10 volunteers (5 men; 31 ± 6.3 years) were imaged at 1.5T. T1 values for myocardium and blood pool were determined for various time points after administration of 0.15 mmol/kg gadobenate dimeglumine using a modified look-locker inversion-recovery sequence before and after administration of ibuprofen over 24 hours. The partition coefficient was calculated as ΔR1myocardium/ΔR1blood, where R1=1/T1.


RESULTS
In vitro no significant correlation was found between relaxivity and ibuprofen concentration, neither in absence (r=-0.15, p=0.40) nor in presence of albumin (r=-0.32, p=0.30). In vivo there was no significant difference in post contrast T1 times of myocardium and blood, respectively and also in the partition coefficient between exam 1 and 2 (p>0.05). There was good agreement of the T1 times of myocardium and blood and the partition coefficient, respectively between exam 1 and 2.


CONCLUSIONS
Contrast enhanced T1 mapping is unaffected by co-medication with the protein binding substance ibuprofen and has an excellent reproducibility.
Department of Radiology, University Hospital Basel, Basel, Switzerland. nadine.kawel@gmx.de
Nadine
N
Kawel
Francesco
F
Santini
Tanja
T
Haas
Johannes M
JM
Froehlich
Jens
J
Bremerich
D000328:Adult; D003287:Contrast Media / Q000008:administration & dosage / Q000378:metabolism*; D005260:Female; D006321:Heart / Q000033:anatomy & histology*; D006801:Humans; D007052:Ibuprofen / Q000097:blood*; D007089:Image Enhancement; D007275:Injections, Intravenous; D016014:Linear Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008536:Meglumine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood; D009206:Myocardium / Q000378:metabolism*; D009942:Organometallic Compounds / Q000008:administration & dosage / Q000097:blood*; D011237:Predictive Value of Tests; D011485:Protein Binding; D015203:Reproducibility of Results; D012709:Serum Albumin / Q000378:metabolism*; D000075462:Serum Albumin, Human; D013997:Time Factors
C422455:ALB protein, human; D003287:Contrast Media; D009942:Organometallic Compounds; D012709:Serum Albumin; C064572:gadobenic acid; D008536:Meglumine; D007052:Ibuprofen; D000075462:Serum Albumin, Human