Fig. 3.

Top panel: This 37 year-old male was found to have an acute thrombotic 90% lesion in the proximal LAD with TIMI 3 flow at the time of cath. cTnI rose from undetectable to 5.80 ng/mL within three hours with no further serial cTns measured. Bottom Panel: This 46 year-old male was found to have an acute thrombotic 90% lesion in the mid-LAD with TIMI 3 flow at the time of cath; cTnI peaked at 4.44 ng/mL. Both interpreters diagnosed both patients as OMI of the LAD using only the ECG and age (no other history provided). Both cases were counted as “false positives” because the TIMI flow of the lesions and the peak recorded cTns were insufficient according to our primary outcome definition. Neither case had any ECG (out of 7 total) meeting STEMI criteria (bottom panel measurements at J-point, relative to QRS onset per 4th Universal Definition of MI: V1 0 mm, V2 1.2 mm, V3 1.6 mm, V4 1.1 mm, V5 0.8 mm V6 0.7 mm). In both cases, serial ECGs evolved in confirmation of abnormal subtle STE.