We report the case of a middle-aged man, without medical history, who suddenly died at his workplace. The autopsy highlighted a pathological heart macroscopically, with multiple small white areas on the left myocardium. Coronary dissection revealed a pseudotumoural fibromyxoid aspect within the anterior interventricular artery (AIVA) and the left main coronary trunk, including reduction in their diameter with tight stenosis. Microscopic examination of these arteries showed fibroinflammatory wall destruction. In the left myocardium, there were multiple focal ischemic areas at different stages of recovery. Our case is an illustration of primary ischemic heart disease due to coronary arteritis, with a pseudotumoural presentation, which was revealed by sudden death. We discuss the cause of death and the etiological diagnosis preceding coronary arteritis.