Visualisation of presence, location, and transmural extent of healed Q-wave and non-Q-wave myocardial infarction

Background A technical advance in contrast-enhanced magnetic resonance imag ing (MRI) has significantly improved image quality. We investigated whether healed myocardial infarction can be visualised as hyperenhanced regions wi th this new technique, and whether assessment of the transmural extent of i nfarction yields new physiological data. Methods 82 MRI examinations were carried out in three groups: patients with healed myocardial infarction; patients with non-ischaemic cardiomyopathy; and healthy volunteers. Patients with healed myocardial infarction were pro spectively enrolled after enyzmatically proven necrosis and imaged 3 months (SD 1) or 14 months (7) later. The MRI procedure used a segmented inversio n-recovery gradient-echo sequence after gadolinium administration. Findings were compared with those of coronary angiography, electrocardiogra phy, cine MRI, and creatine kinase measurements. Findings 29 (91%) of 32 pa tients with infarcts imaged at 3 months (13 nonQ-wave) and all of 19 imaged at 14 months (eight non-Q-wave) showed hyperenhancement. In patients in wh om the infarct-related-artery was identified by angiography, 24 of 25 image d at 3 months and all of 14 imaged at 14 months had hyperenhancement in the appropriate territory. None of the 20 patients with non-ischaemic cardiomy opathy or the 11 healthy volunteers showed hyperenhancement. Irrespective o f the presence or absence of Q waves, the majority of patients with hyperen hancement had only non-transmural involvement. Normal left-ventricular cont raction was shown in seven patients examined at 3 months and three examined at 14 months, but in these cases hyperenhancement was limited to the suben docardium. Interpretation The presence, location, and transmural extent of healed Q-wa ve and non-Q-wave myocardial infarction can be accurately determined by con trast-enhanced MRI.