Effect of contrast dose in the quantification of myocardial extra-cellular volume in adenosine stress/rest perfusion cardiac magnetic resonance examinations
Caballeros M (1), Bartolomé P (1), Fernández González Ó (2), Greiser A (3), García Del Barrio L (1), Pueyo J (1), Bastarrika G (4).
(1) Cardiothoracic Imaging Division, Department of Radiology, Clínica Universidad de Navarra, Pamplona, Spain.
(2) Siemens Healthcare, Madrid, Spain.
(3) Siemens Healthcare GmbH, Erlangen, Germany.
(4) Cardiothoracic Imaging Division, Department of Radiology, Clínica Universidad de Navarra, Pamplona, Spain
Diffuse myocardial fibrosis can be quantified by calculating extra-cellular volume (ECV) from native and post-contrast T1 values using dedicated single bolus contrast medium injection protocols.
To evaluate differences in T1 maps and myocardial ECV measurements in routine stress/rest perfusion cardiovascular magnetic resonance (CMR) examinations after injection of single and double dose of contrast medium.
MATERIAL AND METHODS:
Thirty-seven consecutive patients (30 men; mean age, 62 ± 13 years) underwent clinically indicated adenosine stress/rest perfusion CMR examination to rule out myocardial ischemia following a conventional split-dose contrast medium injection strategy.
Native and post-contrast T1 mapping was performed 15 min after the first (0.1 mmol/kg) and second (0.1 mmol/kg) dose of contrast medium using a breath-held Modified Look-Locker Inversion recovery (MOLLI) sequence. Student's t-test for paired samples, Bland-Altman plots, and concordance-correlation coefficients (CCC) for agreement between T1 and ECV calculations after single and double dose of contrast medium were calculated. Intra- and inter-observer agreement for measurements was also analyzed.
Myocardial T1 values after single and double dose of contrast medium significantly differed (mean difference of 114.1 ± 19.9 ms, P < 0.01). A single dose of contrast agent provided slightly higher ECV values (mean difference of 2.3 ± 1.1%). CCC for ECV calculations was 0.66. Intra- and inter-observer agreement for all measurements was excellent (CCC ≥ 0.83).
Quantification of myocardial ECV on conventional stress/rest perfusion CMR examination is feasible. T1 maps obtained 15 min after 0.1 mmol/kg of contrast medium provide slightly higher myocardial T1 measurements and ECV values compared with T1 maps obtained after a total dose of 0.2 mmol/kg.
CITATION Acta Radiol. 2016 Oct 28. pii: 0284185116674501