Introduction
Cardiac Magnetic Resonance (CMR) is the gold standard technique for evaluating acute myocardial infarction. It primarily uses T2 STIR sequences for myocardial edema assessment, Late Gadolinium Enhancement (LGE) sequences with Contrast Agent (CA) for infarct core evaluation, and balanced Steady-State Free Precession (bSSFP) sequences for functional heart assessment by visualizing cardiac motion throughout the cycle.

Objectives
To assess whether variations in Flip Angle (FA) within bSSFP sequences can be used to identify signs of acute myocardial damage using a new technique called “Flip Angle Mapping”, which does not require CA administration.

Materials and Methods
Eleven consecutive patients with Myocardial Infarction with Non-Obstructive Coronary Arteries (MINOCA) underwent standard CMR with CA and the new technique. Flip Angle Mapping was performed by acquiring two bSSFP image datasets with FA values of 15° and 60°, respectively. FA maps were generated through mathematical calculation, applying the following relationship to each voxel to derive signal intensity: . These maps were created in both color and grayscale scales, with areas of acute myocardial damage identified as those exhibiting the highest ΔSi.

Results and Conclusions
A strong correlation was observed between regions with higher ΔSi in the new technique’s maps and both myocardial edema and infarct damage identified in LGE sequences. These findings suggest that FA Mapping can serve as a valid alternative to LGE sequences for evaluating patients with acute myocardial infarction.