Twenty-four hour heart period variability in systemic sclerosis

Objective. In patients with systemic sclerosis (SSc), an autonomic dysfunction has been implicated in the pathogenesis of Raynaud's phenomenon and gastrointestinal symptoms. To evaluate cardiovascular autonomic function we analyzed the heart rate variability (HRV) on 24 h electrocardiogram recordings. Methods. In 50 patients diagnosed with SSc and 24 control subjects HRV was analyzed for both frequency and time domain. Results. Frequency domain analysis showed reduction of low frequency and high frequency values in the patients with SSc compared to controls (5.52 +/- 0.74 vs 6.04 +/- 0.78 In (ms(2)), p = 0.007; and 4.17 +/- 0.97 vs 4.14 +/- 0.97 In(ms(2)), p = 0.021, respectively). Analysis in the time domain showed no significant differences in any variable between groups. There were no significant differences between the diffuse and the limited form of SSc, Number of ventricular ectopic beats, prevalence of frequent ventricular ectopy, and supraventricular tachycardia episodes were increased in the patients with SSc compared to controls. Conclusion. Spectral analysis of heart period variability suggests cardiovascular autonomic dysfunction in patients with SSc. Better understanding of this complication could help delineate new strategies for the treatment of SSc.