Magnetic resonance assessment of coronary artery bypass grafts

The increasingly widespread use of myocardial revascularization by aortocoronary bypass grafts and the frequent need for their angiographic control require noninvasive imaging procedures able to provide reliable information on their performance. After an overview of angiography as gold standard and the different imaging procedures of aortocoronary bypass grafts alternative to MRI, echocardiography, nuclear cardiology, X-ray or electron beam ultrafast CT, main MRI procedures for the study of aortocoronary bypass, are illustrated together with the results of the personal experience as those of navigator echo technique provided with cardiac and respiratory synchronization (91% sensitivity for aortocoronary bypass occlusion and 97% specificity for patency). In the near future, hardware and software refinements, intravascular contrast media and the application to aortocoronary bypass grafts of flowmetric techniques of phase-velocity mapping will enable the evaluation of bypass stenosis and distal coronary arteries as well as a complete functional graft assessment.