Effect of Thoracic Sympathectomy on Exercise Tolerance and Cardio- Pulmonary Responses to Exercise

Abstract

PURPOSE: Sympathetic denervation may limit exercise performance capacity by reducing cardiac output and/or by negatively affecting skeletal muscle metabolic behavior. To test this hypothesis, we studied the effect of endoscopic thoracic sympathectomy (ETS) for palmar and/or axillary hyperhidrosis on physiological responses at rest, and during submaximal and maximal exercise in 10 healthy patients (7 females and 3 males 18-40 years old) with idiopathic palmar and/or axillary hyperhidrosis. METHODS: T2-T3 thoracoscopic sympathicolysis was performed using a simplified one stage bilateral procedure. Physiological variables were recorded at rest and during sub-maximal (steady-state) and maximal treadmill exercise before and 70 (±7.5, SD) days after bilateral ETS. RESULTS: Palmar and/or axillary hyperhidrosis was relieved in every patient, confirming the T2- T3 denervation. After bilateral ETS exercise performance capacity (peak work rate reached) and peak VO2 were not different than prior to the ETS. However, heart rate was significantly reduced at rest 14%), at sub-maximal exercise (12.3%) and at peak exercise (5.7%) together with a significant increase in oxygen pulse (11.8%, 12.7% and 7.8%, respectively).The rate Pressure Product (RPP) was also significantly reduced following the surgical procedure at all three study stages. All other physiological variables measured remained unchanged during the three study's stages. CONCLUSIONS: It is suggested that sympathetic denervation of the upper limb do not affect exercise performance or mechanical/physiologic efficiency despite a significant reduction in heart rate (at rest and during exercise) which was, most likely, fully compensated by an increase in stroke volume and/or by an improved muscle O2 extraction and/or utilization (as indicated by the increased O2pulse), keeping the cardiac output and oxygen uptake unaffected.