Autonomic involvement, including cardiac denervation, may precede the motor
symptoms of Parkinson’s disease by several years. L-3,4-dihydroxy-6-[18F]
fluoro-phenylalanine is a positron emitter and a true analog of L-dopa, used in
clinical practice to assess striatal dopaminergic integrity. The present study
aimed to assess the feasibility of evaluating cardiac sympathetic denervation in
Parkinson’s disease patients using L-3,4-dihydroxy-6-[18F] fluoro-phenylalanine
positron emission tomography/computed tomography. Patients referred for an
L-3,4-dihydroxy-6-[18F] fluoro-phenylalanine positron emission
tomography/computed-tomography between July 2015 and May 2017 to evaluate
striatal presynaptic dopaminergic integrity underwent a heart positron emission
tomography scan following a brain positron emission tomography scan.
L-3,4-dihydroxy-6-[18F] fluoro-phenylalanine uptake in the left ventricle was
quantified using Carimas software and compared between patients with and
without Parkinson’s disease. The area under the receiver operating characteristic
curve was used to evaluate the ability of the left ventricular mean standardized
uptake value to discriminate between patients with Parkinson’s disease and those
with other extrapyramidal syndromes. Seventy-six patients were included, of whom
52 were diagnosed with Parkinson’s disease. The mean L-3,4-dihydroxy-6-[18F]
fluoro-phenylalanine left ventricular mean standardized uptake value was lower in
the Parkinson’s disease patients compared to the non- Parkinson’s disease
patients (1.08 0.21 vs. 1.24 0.32, P = 0.015). The left
ventricular mean standardized uptake value was able to discriminate between
Parkinson’s disease and non- Parkinson’s disease patients (the area under the
receiver operating characteristic curve = 0.641, P = 0.049). In conclusion,
quantification of cardiac L-3,4-dihydroxy-6-[18F] fluoro-phenylalanine uptake may
be able to differentiate between patients with and without Parkinson’s disease.
Validation of this finding in more substantial, prospective trials are warranted.