Cardiac Autonomic Changes After Thoracic Sympathectomy: A Prospective, Randomized Study

Abstract

We evaluated whether cardiac autonomic changes could be associated with different extent of sympathetic nerve resection in the management of essential palmar hyperhidrosis. Sixty patients with essential palmar hyperhidrosis were randomly allocated to undergo excision of T3 ganglia (sympathicectomy group; n= 30) or to interruption of sympathetic chain at the T2 to T3 level with ganglion sparing (sympathicotomy group; n= 30). Time and frequency domains were measured with a 24-Holter monitor during daytime, nighttime, and 24-hour periods at different interval points (7 days before operation; 24 hours; and 1, 3, and 6 months later), and the differences were statistically compared. Clinical outcomes were also evaluated. Twenty-eight of 30 patients of the sympathectomy and 29 of 30 patients of the sympathicotomy group completed the study. In both groups, we observed a significant increase (p < 0.05) of vagal activity measurements as root mean square of the successive differences of heart period; proportion of adjacent normal R-R intervals >50 ms; high frequency; and a significant decrease (p < 0.05) of adrenergic activity variables as heart rate, low frequency, and the ratio between low frequency and high frequency during daytime, nighttime, and 24-hour periods. These changes were significantly more evident (p < 0.05) in the sympathectomy group than in the sympathicotomy group. Clinical outcomes were similar between the two groups. Endoscopic thoracic sympathectomy caused a shift of sympathovagal balance toward parasympathetic tone that seems to be associated with the extent of denervation. This trial was registered at clinicaltrials.gov as NCT02733497.