Noninvasive coronary imaging.
Noninvasive imaging of the coronary arteries is one of the most important but challenging goals in medical imaging. Recent methods being developed for visualization of the coronary arteries include transthoracic and transesophageal echocardiography, electron-beam computed tomography, and magnetic resonance imaging. Transesophageal echocardiography is a feasible noninvasive technique for imaging the left main coronary artery and detecting hemodynamically significant luminal obstruction. Recent technological advances in transthoracic Doppler echocardiography provide measurement of coronary flow velocity in the distal portion of left anterior descending artery, which is useful for the assessment of coronary flow reserve, and therefore coronary stenosis and restenosis after coronary intervention in left anterior descending artery lesions. Electron-beam computed tomography is a cross-sectional imaging technique with high spatial and temporal resolution. It is possible for image acquisition to be triggered by the patient's electrocardiogram and this technique is well suited to cardiac imaging. Electron-beam computed tomography might be useful to detect or rule out high-grade coronary artery stenoses and occlusions, when image quality is adequate. Recent improvements and progress in coronary magnetic resonance angiography stem from the use of respiratory motion compensation and fast imaging methods. The most commonly used breath-hold method was developed with a fast segmented two-dimensional sequence on thin sections oriented to capture the coronary vessel inplane. Sensitivity and specificity of coronary magnetic resonance angiography in detecting significant coronary artery disease are 90% and 92% using this method.
Kaji
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Division of Cardiology, Kawasaki Medical School, Matsushima 577, Kurashiki, Okayama 701-0192, Japan.
Akasaka
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Yoshida
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D001783:Blood Flow Velocity; D003326:Coronary Circulation; D003327:Coronary Disease / Q000175:diagnosis* / Q000000981:diagnostic imaging; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000473:pathology; D017548:Echocardiography, Transesophageal; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D014057:Tomography, X-Ray Computed