Acute occlusion of the left main trunk presenting as ST-elevation acute coronary syndrome.

Acute obstruction of the left main coronary artery (LMCA) is not frequently encountered. Electrocardiographic findings are important to early diagnosis in determining an acute obstruction of the LMCA, which requires immediate aggressive treatment, in this extremely unstable condition. However, there is no single typical electrocardiographic pattern representing acute occlusion of the LMCA. We describe a rare electrocardiographic finding that suggested ST-elevation acute coronary syndrome of the anterior zone due to left main trunk total occlusion.