Lewy bodies in the sinoatrial nodal ganglion: clinicopathological studies

Lewy bodies (LB) are characteristic pathological findings for idiopathic Parkinson disease, and extracranial organs have also been known to exhibit these structures. Clinically, the possible involvement of LB in cardiac dysfunction has attracted attention based on the findings of studies using [123I] metaiodobenzyl guanidine (MIBG) scintigraphy. The purpose of the present study was to investigate the possible involvement of LB in heart disease. A total of 40 autopsy cases consisting of Lewy body disease and Parkinson syndrome were examined. The former were cases with intracranial LB regardless of clinical symptoms, and the latter were cases with parkinsonism but without intracranial LB. The presence of heart disease or an atrial arrhythmia and the results of an MIBG scintigraphy study were clinically examined. The sinoatrial node was examined microscopically and immunohistochemically. The results showed that heart disease and atrial arrhythmia complications were more frequent in cases with Lewy body disease than in cases with Parkinson syndrome and that LB were frequently found in extracranial organs, especially in the sinoatrial nodal ganglion, in cases with Lewy body disease. In the current report, we hypothesized that neuronal changes involving LB in the sinoatrial nodal ganglion may cause arrhythmia and ischemic heart disease as a result of vasoconstriction.