OBJECTIVE The purpose of the present case report is to describe an extremely rare and unusual coronary interarterial communication. METHODS A 65-year-old female patient admitted with acute coronary syndrome underwent a coronary angiography performed with Judkins technique to obtain standard angiographic views. RESULTS We have demonstrated a very rare interarterial communication traversing an unusual retroaortic path between the body of left circumflex artery and the conus branch of the right coronary artery. CONCLUSIONS Coronary interarterial communications are rarely encountered; however, may fulfill important tasks in the coronary circulation. Therefore, invasive cardiologists and cardiovascular surgeons should be aware of their presence.