Right thoracoscopic sympathectomy alters indexes of the autonomic control of sino-artial node activity
Musialek P., Kardos A., Webb I., Collin J., Hands L., Casadei B., Hospital JR.
Background: Evidence in animals has indicated that right stellectomy can be arrhythmogenic by causing a paradoxical increase in sympathetic activity in the left ventricle. Aim: We evaluated effects of right thoracoscopic sympathectomy (RTS, for palmar/axillary hyperhydrosis) on heart rate variability (HRV), baroreflex sensitivity (BRS), and cardiac output (CO) at rest and during supine steady-state exercise (workrate equal 70% peak VO2) in n = 8 subjects (3 men and 5 women, age 23-42 years). Methods: ECGs (contrôlée breathing at 0.2 Hz) and noninvasive finger blood pressure (Finapress) were recorded before (baseline, B/L) and at least 3 weeks after RTS. Doppler-derived cardiac output was evaluated at rest and during exercise. Cardiac vagal activity was assessed by short-term measurements of HRV in time domain, and the spontaneous sequence method was used to measure BRS. Results are expressed as mean (SEM) HR CO HR CO rest rest exercise exercise SDNN pNNSO BRS (bpm) (a.u.) (bpm) (a.u.) (ms) (%) (ms/mmHg) B/L 69 75 133 142 52 28 14 (4) (10) (5) (17) (5) (7) (3) After RTS 64 69 122 153 70 43 17 (3) (2) (5) (9) (7) (6) (3) p .03 .57 .005 .47 .08 .08 .50 Conclusion: After RTS the autonomie control of sino-atrial activity appears to be shifted towards parasympatetic predominance. ©1998 Scandinavian University Press.