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Abstract Cardiovascular magnetic resonance (CMR) imaging is a great advancement in the field of health care, which has emerged as an important clinical technique in the diagnosis, therapeutics and prognostication of IHD. Early and accurate diagnosis of acute myocardial infarction (MI) is necessary for optimizing management of patients with acute MI and for improving outcome. Magnetic resonance (CMR) new pulse sequences have got the inherently superior soft tissue contrast provided by MR, so that it now provides the reference standard for in vivo viability imaging as well as the assessment of regional and global systolic function, the detection of myocardial infarction and viability and the evaluation of pericardial disease and cardiac masses. Evaluation of AMI (acute myocardial infarction) with magnetic resonance imaging, allows detection of reversible and irreversible injury of the myocardium. Cardiovascular Magnetic Resonance (CMR) in one examination provides an accurate assessment of myocardial function and morphology (edema, impaired microcirculation, hemorrhage, and necrosis). Therefore, CMR has great potential as a diagnostic method in the acute phase of myocardial infarction, providing information on the degree and extent of reversible and irreversible myocardial damage. STIR sequences are commonly applied to detect myocardial edema, combined with Late Gadolinium Enhancement (LGE); STIR images allow the quantification of myocardial salvage index and to distinguish between acute and chronic injuries. Despite all the advantages of STIR imaging, this technique has some limitations; the main shortcomings of this technique are motion artifacts, Partial blood suppression in the area of slow flow leading to a “slow flow artifact” which is often confused with sub-endocardial edema. Moreover Dark-blood preparation pulse may also cause a significant signal loss and variations, which may result in an incorrect diagnosis. Diffusion weighted imaging is a new technique for edema detection in patients with acute myocardial infarction and has higher sensitivity in the detection of myocardial edema than STIR. The sensitivity of the DWI sequence, in contrast to the STIR, does not depend on the infarct location, provides total suppression of the blood signal and reduces the occurrence of motion artifacts. So it may be recommended for the diagnosis of acute injuries, especially in patients with “slow-flow” artifacts in STIR images. As early and accurate diagnosis of acute myocardial infarction (MI) is necessary for optimizing management of patients with acute MI and for improving outcome. DWI was able to show myocardial involvement in 78% of MI patients in less than 1 min acquisition time, with a similar extent assessment as late-gadolinium enhancement sequence. The most important issue is that MI detection with DWI rose to 97% for recent MIs, despite not discriminating from subacute MIs. The earlier is the MR examination after the cardiac event, the better should be the sensitivity of DWI. Diffusion tensor magnetic resonance imaging (DT-MRI) has emerged as a candidate method for nondestructive reconstruction of the fiber structure of the left ventricle and reflect the structural integrity of underlying tissues. It is crucial to investigate the sequential changes of myocardial microstructure and its relationships with changes of macrostructure and function of the left ventricle post-MI; this can be achieved by Diffusion tensor magnetic resonance imaging (DT-MRI). Diffusion spectrum MRI tractography (DSI tractography), is a novel complex technique that was experimented ex-vivo to image myofiber architecture in normal and infarcted myocardium. It resolves multiple myofiber populations per voxel, with the ability to describe fiber crossings. DSI tractography reveals a complex network of orthogonal myofibers within infarcted myocardium which may resist mechanical remodeling but also probably increase the risk for lethal reentrant arrhythmias. Diffusion based MRI sequences had some limitations as it is not yet able to discriminate between MI and acute myocarditis , it did not focus on transmurality of the DWI hypersignal . It cannot be excluded that DWIs provided some false positive results due to the bulk motion artifact. CMR has great potential and as a diagnostic method in the acute phase of myocardial infarction, providing information on the degree and extent of reversible and irreversible myocardial damage. Diffusion weighted imaging (DWI) sequence are sensitive to the increase of water content in the myocardium and may be used as an alternative or in addition to the standard T2- STIR weighted sequences as it raised the MI detection to 97% for recent MIs. The new MR acquisition technique reducing substantially diagnostic imaging times by allowing prompt diagnosis of cardiac ischemic disease should help a better triage of emergency patients, by comparison with biochemical markers such as troponin, the raise of which being frequently delayed by 8 h. Understanding the altered tissue integrity and fiber architecture in diseased myocardium such as myocardial infarction (MI) is critically important because it might shed light on the mechanism of structure-function remodeling after MI. this can be assessed by using DWI . Cardiac DT-MRI can is used to estimate infarct size and a high-resolution viability map is used for zonal segmentation of the infarct, adjacent, and remote zones. It reflects the structural integrity of underlying tissues. |