Figure.

Schematic representation of potential mechanisms of acute MI in patients found to have only mild obstruction or “normal coronary arteries” at coronary angiography. In this figure, a non-obstructive plaque is seen in the proximal left anterior descending coronary artery with apical left ventricular MI. The upper insets demonstrate potential mechanisms of MI, specifically transient thrombotic occlusion with or without embolization of plaque contents, and coronary artery spasm. Final inset (lower) shows restoration of normal flow with minimal residual luminal stenosis.