- Oral presentation
- Open Access
- Published:
Overestimation of infarct size following acute myocardial infarction is related to extent of myocardial edema
Journal of Cardiovascular Magnetic Resonance volume 16, Article number: O21 (2014)
Background
Late gadolinium enhancement (LGE) is an accurate and reproducible method to delineate nonviable myocardium following myocardial infarction (MI). However, in the early stages following acute MI, LGE has been shown to overestimate the size of the infarct zone by up to 30%. The causes for this are unclear, and may be related to tissue remodelling, intracellular contrast uptake, or expansion of the interstitial space. Myocardial edema is a feature of reperfused acute MI, and edematous myocardium has been associated with early contrast enhancement [1]. We hypothesised that the presence of tissue edema is also related to late enhancement, and contributes to overestimation of infarct size in acute MI.
Methods
46 patients received CMR examination at 3.0T at 2 days following reperfused ST-elevation acute MI, with follow-up imaging at 10 days and 3 months. Short-axis T2-weighted imaging and cine imaging were performed, as well as LGE imaging 16-20 minutes following administration of 0.1 mmol/kg gadolinium DTPA. Edema volume was measured on T2-weighted imaging and scar volume measured on LGE imaging, both quantified using a semi-automated histogram-based thresholding method (Otsu method). The change in scar volume was compared to the change in edema volume between day 2 and day 10, and between day 2 and 3 months.
Results
Of the 46 patients studied, 27 (59%) completed imaging at day 10 and 39 (85%) at 3 months. Mean scar volume decreased by 7 ml (23%, p < 0.01) at 10 days and 9 ml (28%, p < 0.01) at 3 months. There was significant correlation between change in edema volume and change in scar volume from day 2 to day 10 (r = 0.62, p < 0.01) and day 2 to 3 months (r = 0.66, p < 0.01) (Figure 1). Stratifying patients into two groups based on mean change in edema volume, patients with more change in edema had significantly higher change in scar volume (Figure 2).
Conclusions
LGE CMR overestimates scar volume acutely following acute reperfused MI. This overestimation correlates with the volume of myocardial edema detected acutely.
Funding
JPG and SP receive a research grant from Philips Healthcare. SP is funded by British Heart Foundation fellowship (FS/10/62/28409).
References
Matsumoto, et al: JACC Cardiovasc Imaging. 2011
Author information
Authors and Affiliations
Rights and permissions
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. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
About this article
Cite this article
Kidambi, A., Uddin, A., Ripley, D.P. et al. Overestimation of infarct size following acute myocardial infarction is related to extent of myocardial edema. J Cardiovasc Magn Reson 16 (Suppl 1), O21 (2014). https://doi.org/10.1186/1532-429X-16-S1-O21
Published:
DOI: https://doi.org/10.1186/1532-429X-16-S1-O21
Keywords
- Myocardial Infarction
- Acute Myocardial Infarction
- Infarct Size
- Late Gadolinium Enhancement
- Late Enhancement