Cardiac sympathetic denervation in bradykinesia-dominant Parkinson's disease

Cardiac iodine-123-labeled-metaiodobenzylguanidine uptake is reduced in early-stage Parkinson's disease, suggesting sympathetic nerve degeneration. The scintigraphic findings in patients with Parkinson's disease with different clinical features have, however, not been established. Iodine-123-labeled-metaiodobenzylguanidine myocardial scintigraphy was performed in 143 patients with Parkinson's disease. The early and delayed heart to mediastinum ratios were analyzed according to the dominant motor deficit (tremor, bradykinesia, rigidity, and postural instability), age, sex, age at onset, disease duration, and Hoehn and Yahr stage. Both ratios correlated with bradykinesia, age at disease onset, and disease duration; but not with sex, Hoehn and Yahr stage, tremor, rigidity, and postural instability. Our results suggest a close link between myocardial sympathetic degeneration and bradykinesia, age at onset and disease duration.