The occurrence of an acute coronary syndrome (ACS) with an anomalous connection of coronary artery (ANOCOR) identified as a culprit artery is very rare. This association may lead in some anatomical forms to a delay in coronary reperfusion. We report the clinical case of a patient admitted for high-risk Non ST elevation myocardial infarction (NSTEMI) in whom coronary angiography accidentally discovers an anomalous connection of the left coronary network from the right anterior. In light of this case and a review of literature, we discuss the peculiarities of these anomalous connections.