Session Information
Date: Wednesday, September 25, 2019
Session Title: Neuroimaging
Session Time: 1:15pm-2:45pm
Location: Les Muses Terrace, Level 3
Objective: Describe long-term trends in indices of cardiac sympathetic innervation and function in synucleinopathies.
Background: A group of neurodegenerative diseases including Parkinson disease (PD), pure autonomic failure (PAF), and multiple system atrophy (MSA) are characterized by cytoplasmicdeposition of the protein alpha-synuclein in the brain and are termed synucleinopathies. Lewy body forms of synucleinopathy also involve decreased cardiac sympathetic innervation and a vesicular storage defect in residual noradrenergic nerves. Long-term trends in indices of cardiac sympathetic innervation and function have not been described in these synucleinopathies.
Method: Patients with PD (N=31), PAF (N=9), or MSA (N=9) underwent initial and follow-up 18F-dopamine positron emission tomography (median follow-up 3.5 years). Interventricular septal 18F-dopamine-derived radioactivity 8 minutes after tracer injection (8’ radioactivity) was used to indicate sympathetic innervation and the slope of mono-exponential decline of radioactivity between 8 and 25 minutes (k8’-25’) to indicate intraneuronal vesicular storage. Healthy volunteers (HVs) were controls (N=33).
Results: PD and PAF patients had lower 8’ radioactivity and higher k8’-25’ values than did HVs (p<0.0001 each); values in MSA patients did not differ from HVs. In PD 8’ radioactivity decreased between the initial and last follow-up visit (> 30% decrease, p<0.0001) but did not decrease in MSA. In all groups k8’-25’values did not change during follow-up. Eight subjects with normal 8’ radioactivity (>6,000 nCi-kg/cc-mCi) and subsequently decreased radioactivity had initial k8’-25’ values higher than in HVs (p=0.026).
Conclusion: Neuroimaging evidence of decreased vesicular uptake in cardiac sympathetic nerves is present upon initial evaluation of patients with Lewy body diseases and may provide a biomarker of catecholaminergic dysfunction early in the disease process.
To cite this abstract in AMA style:
G. Lamotte, C. Holmes, T. Wu, D. Goldstein. Long-term changes in myocardial sympathetic innervation and function in synucleinopathies [abstract]. Mov Disord. 2019; 34 (suppl 2). https://www.mdsabstracts.org/abstract/long-term-changes-in-myocardial-sympathetic-innervation-and-function-in-synucleinopathies/. Accessed November 21, 2024.« Back to 2019 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/long-term-changes-in-myocardial-sympathetic-innervation-and-function-in-synucleinopathies/