３．MRI：①心臓診断

Cardiac magnetic resonance(MR)imaging has been recognized as reliable means for accurate evaluation of cardiac anatomy and ventricular function. Late gadolinium-enhanced MR imaging can clearly delineate subendocardial infarction, and the assessment of transmural extent of infarction on late enhanced MR imaging has proved to be useful in predicting functional recovery of dysfunctional myocardium in patients after myocardial infarction. Stress first-pass contrast enhanced myocardial perfusion MR imaging can detect subendocardial ischemia, and recent studies demonstrated the high diagnostic accuracy of stress myocardial perfusion MR imaging in detecting significant coronary artery diseases. By combining stress perfusion MR imaging and late gadolinium MR imaging, infarcted myocardium and ischemic but viable myocardium can be differentiated. Free breathing, whole heart coronary MR angiography has recently been introduced as a method that can detect coronary artery stenosis, with the diagnostic accuracy comparable to 16-slice computed tomography (CT). MR flow measurement is useful in quantifying valvular regurgitation volume, shunt volume in congenital heart diseases, and blood flow in coronary artery bypass grafts. Cardiac MR imaging can play a pivotal role in managing patients with ischemic heart diseases.