Kyunghee Lee MD, Abstract Co-Author: Nothing to Disclose

Eun Ju Chun, Abstract Co-Author: Nothing to Disclose

Sang Il Choi MD, Presenter: Nothing to Disclose

Jeong A Kim, Abstract Co-Author: Nothing to Disclose

To describe MR imaging features specific for aborted myocardial infarction in patients with ST-segment elevation.

Among the MRI data of 57 consecutive patients with STEMI between Feb. 2006 and Dec. 2008, we prospectively reviewed and included 11 patients who finally revealed aborted MI in this study. Initial MRI including T2-weighted spin-echo imaging (T2WI), cine MRI, first-pass perfusion and delayed enhancement MRI (DE-MRI) was performed in 5 ± 2 days after revascularization. We determined the location, homogeneity, signal intensity of abnormal area on T2WI and enhancement pattern of DE-MRI. For quantitative analysis, we calculated the signal intensity ratio (SR) of the diseased myocardium compared to remote myocardium on T2WI and DE-MRI. Besides, we evaluated the regional systolic function on cine MRI and perfusion abnormality on first-pass perfusion imaging. After six months, MRI was repeated to see changes in enhancement pattern and functional indices over time.

On T2WI, all patients showed homogenous high signal intensity along the vascular territory of culprit lesion. There was no difference in T2 signal intensity between aborted MI and overt MI groups. On DE-MRI, enhancement pattern showed as diffuse fuzzy enhancement (n=3), spotty discrete enhancement (n=2), and mixed type (n=3). In quantitative analysis, mean value of SR on T2WI and DE-MRI images is 1.50 and 2.45, respectively. All cases showed hypokinesia and subendocardial perfusion defect at the corresponding vascular territory, except one. On 6-month F/U images, characteristic delayed enhancement and cardiac function indices normalized in most of the cases.

On MRI, both aborted MI and overt MI showed diffuse homogeneous high signal intensity along the vascular territory on T2WI. However, comparing with overt myocardial infarction, we suggest that diffuse fuzzy or spotty enhancement be the specific finding of aborted myocardial infarction on DE-MRI. Furthermore, cardiac MRI can enable the differentiation of aborted MI from masquerading MI.

Cardiac MRI can enable the differentiation of aborted MI from masquerading MI.

Lee, K, Chun, E, Choi, S, Kim, J, Aborted Myocardial Infarction in Patients with ST-Segment Elevation: Evaluation of Comprehensive MR Imaging  .  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9014558.html