- Poster presentation
- Open Access
- Published:
Visualization and characterization of transmural gradients in high resolution first pass perfusion images
Journal of Cardiovascular Magnetic Resonance volume 12, Article number: P247 (2010)
Introduction
High spatial resolution imaging enables detailed assessments of the spatial variation of myocardial perfusion. Transmural gradients in myocardial perfusion are of particular interest, as the endocardium is more sensitive to ischaemia from a coronary stenosis than the epicardium. Gradients in myocardial perfusion are also seen in left ventricular hypertrophy and microvascular disease.
Purpose
We present a new method to visualize and characterize the temporal evolution, severity and extent of subendocardial to subepicardial gradients in myocardial contrast uptake on first-pass myocardial perfusion CMR.
Methods
Our new method relies on high spatial resolution imaging and an integrated motion compensation algorithm to enable extraction of signal intensity curves in layers within the myocardium. By subtracting signal intensities of the epicardial and endocardial layers, a so-called "gradientogram" is generated, in which the horizontal axis corresponds to time, the vertical axis corresponds to the angular position and the grey values correspond to the transmural gradient in contrast uptake. From each line in the gradientogram, the mean and peak gradient can be measured. Moreover, perfusion deficits causing a transmural gradient appear as dark blobs that can be segmented to allow for quantitative characterization, which can include measurements related to the gradient amplitude (i.e. intensities within the segmentation), the temporal persistence (i.e. the width of the segmentation) and the circumferential extent (i.e. the height of the segmentation) in which transmural gradients occur.
Results
We tested our method on a negative and a positive case. First-pass perfusion images were acquired using high resolution kt-accelerated imaging. Visualization of gradientograms after motion compensation and contour delineation revealed a clear distinction between the negative (figure 1ab, homogenous gradientogram) and positive case (figure 1cd, dark signal corresponding to an inferior perfusion defect). Measurements of the mean and peak gradient were visualized in a bull's eye plot (figure 2). Quantitative characterization of the segmented gradientogram at all slices of the positive case showed that the transmural gradient spanned 42.7-146.4 degrees, persisted for 6.4-15.7 seconds and had an average amplitude of 93.2-161.5.
Conclusion
We have developed a novel method to visualize and characterize transmural gradients in myocardial contrast uptake. More extensive validation experiments will be performed to establish the clinical value of our method.
Author information
Authors and Affiliations
Rights and permissions
Open Access This article is published under license to BioMed Central Ltd. This is an Open Access article is distributed under the terms of the Creative Commons Attribution 2.0 International License (https://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
About this article
Cite this article
Hautvast, G.L., Chiribiri, A., Breeuwer, M. et al. Visualization and characterization of transmural gradients in high resolution first pass perfusion images. J Cardiovasc Magn Reson 12 (Suppl 1), P247 (2010). https://doi.org/10.1186/1532-429X-12-S1-P247
Published:
DOI: https://doi.org/10.1186/1532-429X-12-S1-P247
Keywords
- Myocardial Perfusion
- Coronary Stenosis
- Motion Compensation
- Peak Gradient
- High Spatial Resolution Imaging