Spontaneous coronary artery dissection (SCAD) is a rare disease, occurring most often in young women, around 40 years of age. Usually there is the presence of several predisposing factors. Diagnosis is made using coronary angiography, optical coherence tomography (OCT) or autopsy. Optical coherence tomography allows a precise diagnosis to be made, identifying as it can, a coronary artery intramural haematoma prior to the occurrence of a dissecting lesion. The case of a 52-year-old woman with SCAD of unknown etiology is reported.