AbstractBackgroundThe anomalous origin of the left circumflex artery from the pulmonary artery (ACXAPA) is a very rare coronary anomaly. Only a few cases have been reported until today, from incidental findings to autopsy reports after sudden cardiac death.Case summaryWe report here for the first time the case of a man, previously monitored for asymptomatic left ventricular non-compaction cardiomyopathy, who presented with non-ST myocardial infarction and was diagnosed with ACXAPA. Complementary tests confirmed ischaemia in the corresponding territory, and the patient was referred to surgery for reimplantation of the circumflex artery.DiscussionLeft ventricular non-compaction cardiomyopathy is a rare congenital cardiomyopathy whose association with coronary anomalies, not with ACXAPA, had previously been described until now. A related embryological origin could potentially explain this association. The management of a coronary anomaly should indicate dedicated multimodality cardiac imaging in order to not disregard the association with underlying cardiomyopathy.