Evaluation of cardiovascular autonomic dysfunction according to heart rate turbulence and variability in patients with relapsing remitting multiple sclerosis

Abstract

Background/aim: Multiple sclerosis MS is an autoimmune disease characterized by neurodegeneration or demyelination; the relapsing-remitting phase of MS is characterized by acute exacerbation of disease activity. The most commonly used noninvasive approach to assess autonomic function is the determination of heart rate turbulence HRT and heart rate variability HRV . The aim of this study was to evaluate the presence of cardiovascular autonomic dysfunction using HRT and HRV parameters determined via 24-h Holter ECG monitoring in patients with relapsing-remitting MS without known heart disease. Materials and methods: The study included 26 patients diagnosed with relapsing-remitting MS and 22 age- and sex-matched healthy controls. HRT and HRV parameters were analyzed via 24-h Holter ECG monitoring. Magnetic resonance imaging findings were reevaluated to identify any demyelinating lesions in the brain stem. Results: The HRV parameters of SDNNI mean of the standard deviations of all normal sinus RR intervals in all 5-min segments , rMSSD root-mean-square successive difference , and sNN50 percentage of successive normal sinus RR intervals >50 ms were significantly lower in the MS group than in the control group P