P318 Heart rate variability is not able to detect cardiovascular autonomic dysfunction in patients with clinically isolated syndrome

Abstract

Objectives To determine differences in heart rate variability (HRV) in a large cohort of patients with clinically isolated syndrome (CIS) compared to healthy controls (HC). Methods Two hundred CIS patients (134 females, mean age 32.67 ± 9.17 years) and 58 HC (38 females, mean age 30.93 ± 9401 years) were enrolled. In all participants ECG was recorded during 10 min in both supine and 70° tilt-up position. HRVanalysis was performed by Kubios HRV 2.2. Following HRV parameters were compared between groups: total power of low (LF) and high frequency domain components (HF), normalized HF (HFnu), low-to-high frequency ratio (LF/HF), standard deviation of normal-to-normal intervals (SDNN). Results No differences were found between groups in LF (733.41 ± 820.45 vs 617.69 ± 516.17, p = 0.592), HF (829.54 ± 1373.34 vs 890.33 ± 1055.49, p = 0.929), HFnu (45.93 ± 18.80 vs 48.43 ± 20.93, p = 0.397), LH/HF (1.66 ± 1.65 vs 1.62 ± 1.51, p = 0.616) and SDNN (37.66 ± 19.94 vs. 37.61 ± 18.35, p = 0.991) in the supine position. No differences were found between groups in LF (638.44 ± 786.26 vs 648.86 ± 537.22, p = 0.321), HF (184.74 ± 291.09 vs 179.07 ± 208.27, p = 0.556), HFnu (22.67 ± 14.67 vs 23.08 ± 16.81, p = 0.895), LH/HF (5.65 ± 4.71 vs 5.84 ± 4.85, p = 0.669) and SDNN (27.46 ± 13.03 vs 28.13 ± 10.40, p = 0.719) in the tilt-up position. Discussion Recent studies have shown that autonomic dysfunction measured with Composite autonomic scoring scale (CASS) is present in half of CIS patients. The results of the present study suggest that CASS is superior compared to HRV analysis in the detection of autonomic dysfunction in CIS. Conclusion No differences were observed in HRV analysis between CIS patients and healthy controls during supine and tilt-up position. Significance HRV analysis is normal in patients with clinically isolated syndrome.