Seventeen patients underwent MRI spin-echo imaging (Magniscan 5000) 7 to 21 days after acute myocardial infarction (10 anterior, 7 inferior--average 13.1 +/- 3.7 days). The success rate of visualisation of AMI evaluated independently by a qualitative score (from 0 to 4) based on the brilliance of the myocardial signal after taking steps to eliminate the brillance of pericardial fat and subendocardial flow signals, was 3.1 +/- 0.87 in anterior AMI (10 out of 10) and 1.28 +/- 1.25 (4 out of 7) in inferior AMI (p less than 0.007). The diagnostic sensitivity was increased when images of the third echo were used (13 out of 17) compared to those of the second echo (8 out of 17, p less than 0.016). The value of the 3rd echo is explained and emphasised. Abnormal intramyocardial signals were not recorded in a control group of 10 patients under similar conditions of multi-echo imaging. Finally, significant correlations were observed between peak CPK concentrations and the MRI score (r = 0.62; p less than 0.01) and between peak CPK and the number of sections in which the hyperbrilliant signal was observed (r = 0.74; p less than 0.001): this may open the day to quantification of myocardial necrosis by MRI.