<p>In this case report, sudden cardiac death caused by intussusception of a coronary artery is discussed. A 47-year-old man was found dead in the nursing home where he lived, following an episode of polyphagia and two of vomiting. Upon cadaveric dissection, an overdistention of the large intestine was noted. Re-evaluation of the formalin-fixed whole heart revealed occlusion of the circumflex branch of the left coronary artery, which was not macroscopically attributable to vascular thrombosis or an atheromatous plaque. Histological investigations revealed ischaemic-type histological changes of the left ventricular wall in a hyperacute phase of evolution and, in the occluded coronary branch, extensive intraluminal invagination of the intima and media, as occurs in vascular intussusception. Further stains revealed the presence of fibromuscular dysplasia of the wall of the affected vessel. The subject’s death was ascribable to an acute cardiovascular failure secondary to acute ischaemic myocardial injury induced by intussusception of a coronary artery affected by dysplastic degeneration. These findings fully account for death by a mechanism sustained both by a mechanical deficit of the cardiac pump and by the possible onset of arrhythmias. Arterial intussusception is a rare complication of spontaneous coronary artery dissection. It is assumed that a combination of predisposing factors, which weaken the arterial wall, and trigger events, such as Valsalva-like activities, underlie the onset of the latter condition. This case highlights the importance of considering rare causes of sudden cardiac death. Greater awareness of these conditions can contribute to a more accurate identification of causes of death, with significant implications in both forensic and clinical settings.</p>