PurposeAnomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital anomaly of the origin of the coronary arteries. The prevalence of this anomaly in the adult patient population is low, and therefore there is virtually no original research on this topic. Reports are limited to case reports.Material and methodsWe evaluated 16,264 computed tomography (CT) exams (cardiac and chest) performed in our heart imaging department between 2015 and 2022 on a dual source 128-slice CT scanner (SOMATOM Definition Flash, Siemens Healthineers, Forchheim, Germany) and established a retrospective registry of adult patients (> 18 years old) with ALCAPA. The study included 7 cases. Next, we collected clinical and echocardiographic data, which could be assessed retrospectively.ResultsWe found 7 cases of ALCAPA in adult patients (0.043%). Three of them were female, and 4 were male. The age varied between 20 and 60 years. Echocardiographic findings, as well as the clinical course, varied widely.ConclusionsALCAPA is an extremely rare anomaly, which nonetheless must be taken into clinical consideration. This lesion may be fatal during infancy. Data regarding adult patients is scarce. Multicentre registries are needed to establish a more detailed clinical profile of adults with this anomaly.