- Poster presentation
- Open Access
Three-compartment (3C) pharmacokinetic modeling is more accurate than two-compartment (2C) modeling of myocardial fibrosis gadolinium kinetics
© Goldfarb et al; licensee BioMed Central Ltd. 2012
- Published: 1 February 2012
- Myocardial Fibrosis
- Normal Myocardium
- Extracellular Volume
- Gadolinium Base Contrast Agent
- Chronic Myocardial Infarction
We observed significantly different curve shapes in healed chronic myocardial infarction when compared with normal myocardium and found that gadolinium kinetics was more accurately modeled (greater R2) with a 3C model rather than a 2C model. 2C Modeling of fibrotic and normal myocardium showed both a significant difference between the transport into the tissue and extracellular volumes while 3C modeling showed only a significant difference between the extracellular volumes of fibrotic and normal myocardium as well as the functional existence of a third compartment in fibrotic and not in normal myocardium.
There is increased interest in the quantitative assessment of myocardial gadolinium enhancement. There are a number of preclinical and clinical studies that have show the utility of MR derived variables for the assessment of dense as well as diffuse myocardial fibrosis. These studies use blood and myocardial T1 measurements followed by calculations of blood-tissue partition coefficients and tissue fractional volumes (gadolinium volume of distribution (Vd) and extracellular volume (Ve)). The typical assumption is that two-compartmental myocardial tissue modeling is sufficient. This assumes that the gadolinium based contrast agent (GBCA) freely passes into and out of and freely distributes within both normal and diseased myocardial tissue. Most publications assume a 2C model where only the volume of distribution changes in fibrotic myocardium. With this assumption, the GBCA time course curve shapes should remain the same and only the GBCA concentration and hence image signal should increase as there is increased GBCA per unit tissue of myocardium.
3C modeling of GCBA kinetics provides a more accurate fit to modeling of healed myocardial infarction. There may not be a physical third compartment, but the better fit could suggest trapping of GBCA in fibrotic myocardium, possibly due to GBCA binding.
American Heart Association Scientist Development Grant, 0635029N.
This article is published under license to BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.