  Automated extraction of quantitative parameters from Cardiac Magnetic
Resonance Images (CMRI) is crucial for the management of patients with
myocardial infarct. This work proposes a post-processing procedure to jointly
analyze Cine and Delayed-Enhanced (DE) acquisitions in order to provide an
automatic quantification of myocardial contraction and enhancement parameters
and a study of their relationship. For that purpose, the following processes
are performed: 1) DE/Cine temporal synchronization and 3D scan alignment, 2) 3D
DE/Cine rigid registration in a region about the heart, 3) segmentation of the
myocardium on Cine MRI and superimposition of the epicardial and endocardial
contours on the DE images, 4) quantification of the Myocardial Infarct Extent
(MIE), 5) study of the regional contractile function using a new index, the
Amplitude to Time Ratio (ATR). The whole procedure was applied to 10 patients
with clinically proven myocardial infarction. The comparison between the MIE
and the visually assessed regional function scores demonstrated that the MIE is
highly related to the severity of the wall motion abnormality. In addition, it
was shown that the newly developed regional myocardial contraction parameter
(ATR) decreases significantly in delayed enhanced regions. This largely
automated approach enables a combined study of regional MIE and left
ventricular function.
