Cardiac magnetic resonance spectroscopy in Parkinson’s disease

Scientific Background Parkinson`s disease is a neurodegenerative disorder presenting with characteristic motor symptoms including bradykinesia, tremor, rigidity and postural instability. The umbrella term parkinsonian syndromes embrace a group of disorders with overlapping clinical presentations which frequently hamper an early differential diagnosis. Multiple system atrophy belongs to the latter group of disorders. In contrast to multiple system atrophy, Parkinson`s disease is accompanied by reduced sympathetic innervations of the myocardium an observation that is commonly used in clinical practice to differentiate the two entities by nuclear medicine diagnostics (123I- Metaiodobenzylguanidine scintigraphym, MIBG). Novelty of the study Despite being utilized for many years in the early differential diagnosis between Parkinson`s disease and multiple system atrophy, 123 I-MIBG scintigraphy has some pitfalls which limits its employment in clinical routine: (i) several commonly used medications (e.g., anti-depressants and Calcium-antagonists) can interfere with MIBG uptake; (ii) MIBG scintigraphy imply a radiation exposure; (iii) nuclear medicine diagnostics have high operational costs (both radiopharmaceutical agent and infrastructures); (iv) the availability of MIBG scintigraphy is limited to academic and research centers. Therefore, cardiac magnetic resonance spectroscopy might represent a valuable and cost-effective alternative tool in the early differential diagnosis between PD and MSA. However, in parkinsonian syndromes, disease-specific metabolic patterns of sympathetic denervation have not been established using cardiac magnetic resonance spectroscopy. Thus, we will cross-sectionally study cardiac magnetic resonance spectroscopy in Parkinson`s disease, multiple system atrophy as well as healthy controls and relate the findings to the current gold standard, i.e. MIBG scintigraphy.

Scientific BackgroundParkinson's disease is a neurodegenerative disorder presenting with characteristic motor symptoms including bradykinesia, tremor, rigidity and postural instability. The umbrella term parkinsonian syndromes embrace a group of disorders with overlapping clinical presentations which frequently hamper an early differential diagnosis. Multiple system atrophy belongs to the latter group of disorders. In contrast to multiple system atrophy, Parkinson's disease is accompanied by reduced sympathetic innervations of the myocardium an observation that is commonly used in clinical practice to differentiate the two entities by nuclear medicine diagnostics (123I-Metaiodobenzylguanidinescintigraphy, MIBG).Novelty of the studyDespite being utilized for many years in the early differential diagnosis between Parkinson's disease and multiple system atrophy, 123 I-MIBG scintigraphy has some pitfalls which limits its employment in clinical routine: (i) several commonly used medications (e.g., anti-depressants and Calcium-antagonists) can interfere with MIBGuptake; (ii) MIBG scintigraphy imply a radiation exposure; (iii) nuclear medicine diagnostics have high operational costs (both radiopharmaceutical agent and infrastructures); (iv) the availability of MIBG scintigraphy is limited to academic and research centers. Therefore, cardiac magnetic resonance spectroscopy might represent a valuable and cost-effective alternative tool in the early differential diagnosis between PD and MSA. Key resultsIn the present project, we were able to demonstrate that cardiac magnetic resonance spectroscopy can be performed easily in patients with neurodegenerative parkinosnism. Unfortunately, thus far, we were unable to establish disease-specific metabolic patterns; however, post-study refinements of read-outs are still pending. In addition, the present project prompted the conduct of numerous follow-up projects that are currently underway.