Progressive disturbance of cardiac sympathetic nerve in Parkinson's disease

Cardiac uptake of meta-iodobenzylguanidine (MIBG) is often decreased in patients with Parkinson's disease (PD) by [123I]MIBG myocardial scintigraphy, and indicates disturbance of cardiac sympathetic nerve. This imaging technique might provide a new diagnostic tool to differentiate PD from other movement disorders with similar symptomatology. The purpose of this study is to clarify whether or not disturbance of cardiac sympathetic nerve progresses over time in PD. [123I]MIBG myocardial scintigraphy was repeated after a mean of 2 years from the first scan in 18 patients with early disease stages of PD (Hoehn-Yahr stage I, II). The mean early and late phase of heart-to-mediastinum (H/M) ratio were 2.03±0.32 and 1.83±0.24 in the first scans, and 1.87±0.32 and 1.64±0.25 in the second scans. The mean early and late phase of H/M ratio in the second scans were significantly lower than those at the first scan (p<0.05 and p<0.001). These results suggest that disturbances of cardiac sympathetic nerve progresses over time in PD. (author)