[Early alterations of adrenergic cardiac function in Parkinson's disease]. / Alteración precoz de la función adrenérgica cardíaca en la enfermedad de Parkinson.

INTRODUCTION: Myocardial sympathetic (adrenergic) function is significantly affected in patients with idiopathic Parkinson's disease (PD) as is deduced from the cardiac scintigraphy evaluation with 123I-metaiodobenzylguanidine (123I-MIBG). PATIENTS AND METHODS: In the present study, 60 patients with PD were studied compared to 17 normal subject without neurological disease. The clinical parameters evaluated were severity of the condition (measured by Hoehn and Yahr Scale), vegetative manifestations, development time and use and type of medication taken. Myocardial adrenergic function was analyzed by imaging with 123I-MIBG. Early (15 min) and delayed (4 h) images of the anterior view were obtained after injection of 123I-MIBG. Qualitative and semiquantitative 123I-MIBG uptake was quantified by calculating a heart-to-mediastinum (H/M) ratio. RESULTS: We found a significant decrease of H/M ratio in patients with PD as compared with controls (p < 0.01) independently of development time, severity of the condition, use of medication or vegetative manifestations. CONCLUSIONS: There is an important noradrenergic alteration in PD, that can be detected from early stages and does not exist in other parkinsonisms caused by a different pathogenic mechanism.