Sudden unexpected death in early Parkinson's disease: neurogenic or cardiac death?

We present two cases of sudden unexpected death (SUD) in elderly individuals in whom autopsy unexpectedly showed Lewy pathology, a hallmark of Parkinson's disease. Both individuals were 68-year-old men who were found dead in their homes without lethal trauma or poisoning. Inquests into their deaths suggested that nonmotor cardiovascular signs of Parkinson's disease might have appeared just before their deaths, although few typical motor signs were present. Autopsy showed Lewy pathology in the heart and peripheral autonomic nervous system in addition to lesser involvement of the brainstem that was consistent with Braak stage 3. In case 1, an atrial septal defect of the secundum type with advanced fibrosis of the atrium was present. In case 2, severe stenosis of the atrioventricular node artery with some microscars and diffuse interstitial fibrosis of the basilar ventricular septum were found. These two cases show some premotor Parkinson's disease with a symptom suggestive of autonomic dysregulation which may be a risk of SUD. In addition, coexistence of structural change of the heart with possibly arrhytthmogenic potential may increase the risk of SUD with Parkinson's disease. Present two cases showed neuropathological examination to detect Lewy pathology in the peripheral nervous system may be important for revealing the cause of some cases of SUD in the elderly, even if typical motor signs were not evident before death.