MRI?A of coronary artery can also show distinct plaque components i.e. calcification, fibrous, thrombotic core, and lipid core.
At present, achieving the best resolution on images of the coronary arteries requires catheterization, injection of an iodinated contrast agent, and use of an x-ray technique. As an alternative, multidetector-row CT (MDCT) or MRI may be used to clarify coronary anatomy and to determine whether a vessel is occluded. Stress imaging has a complementary role in depicting zones with inducible ischemia (blood supply inadequate for the demands of the tissue). Stress may be produced with exercise, an infusion of a medication that increases the strength of cardiac contractions (eg, dobutamine), or an infusion of a medication (eg, adenosine, dipyridamole) that dilates the vessels and thereby reduces the delivery of blood diseased branches.
More than a decade ago, MRI was shown to be capable of imaging the coronary arteries and demonstrating stenoses without catheterization or injection of contrast material.1 More recently, MDCT is proving to be a fast and accurate alternative for defining the coronary anatomy.2 MRI takes more time than MDCT and generally provides less detail of the coronary anatomy, but it avoids ionizing radiation and the use of iodinated contrast agent.
Advances in MRI and CT have markedly improved the speed and resolution of imaging, making these modalities useful in the clinical evaluation of CAD and improving their safety and convenience. In addition to defining the anatomy, both MRI and CT can be used to identify zones of impaired blood supply by timing of the arrival of contrast agent–labeled blood.
In addition, MRI is useful in identifying the location and thickness of myocardial scars. Although neither MRI nor CT has replaced x-ray angiography as the clinical standard for the diagnosis of coronary stenosis, interest in their use in determining if a vessel is open is increasing. Recently, 64-slice multidetector-row CT angiography (CTA) has shown promise as an alternative to x-ray angiography for the identification of coronary blockages.3
At present, achieving the best resolution on images of the coronary arteries requires catheterization, injection of an iodinated contrast agent, and use of an x-ray technique. As an alternative, multidetector-row CT (MDCT) or MRI may be used to clarify coronary anatomy and to determine whether a vessel is occluded. Stress imaging has a complementary role in depicting zones with inducible ischemia (blood supply inadequate for the demands of the tissue). Stress may be produced with exercise, an infusion of a medication that increases the strength of cardiac contractions (eg, dobutamine), or an infusion of a medication (eg, adenosine, dipyridamole) that dilates the vessels and thereby reduces the delivery of blood diseased branches.
More than a decade ago, MRI was shown to be capable of imaging the coronary arteries and demonstrating stenoses without catheterization or injection of contrast material.1 More recently, MDCT is proving to be a fast and accurate alternative for defining the coronary anatomy.2 MRI takes more time than MDCT and generally provides less detail of the coronary anatomy, but it avoids ionizing radiation and the use of iodinated contrast agent.
Advances in MRI and CT have markedly improved the speed and resolution of imaging, making these modalities useful in the clinical evaluation of CAD and improving their safety and convenience. In addition to defining the anatomy, both MRI and CT can be used to identify zones of impaired blood supply by timing of the arrival of contrast agent–labeled blood.
In addition, MRI is useful in identifying the location and thickness of myocardial scars. Although neither MRI nor CT has replaced x-ray angiography as the clinical standard for the diagnosis of coronary stenosis, interest in their use in determining if a vessel is open is increasing. Recently, 64-slice multidetector-row CT angiography (CTA) has shown promise as an alternative to x-ray angiography for the identification of coronary blockages.3
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