STEMI involving left main coronary artery

This code signifies an acute ST elevation myocardial infarction (STEMI) specifically affecting the left main coronary artery. This is a severe type of heart attack caused by a complete blockage in the primary artery supplying blood to a large portion of the heart muscle. It indicates an active, ongoing ischemic event requiring immediate intervention.

Apply this code when documentation clearly states an acute STEMI and explicitly identifies the left main coronary artery as the infarct-related artery. This typically occurs in emergency settings following diagnostic findings such as characteristic EKG changes (ST elevation) and elevated cardiac biomarkers, confirmed by angiography.

• Always verify the specific coronary artery involved; do not assume left main if not explicitly documented.
• Distinguish between initial and subsequent encounters for myocardial infarction using appropriate seventh characters.
• Code any associated complications, such as heart failure or arrhythmias, separately.