Infra-stellate upper thoracic sympathectomy results in a relative bradycardia during exercise, irrespective of the operated side.
OBJECTIVE
Removal of accessory fibres coming from the sub-stellar thoracic chain to the heart during infra-stellate surgical upper thoracic sympathectomy (ISS) may be responsible for a decreased heart rate to workload relationship during exercise following surgery. We hypothesised that heart rate would decrease not only following right ISS.


METHODS
We performed repeated bicycle incremental exercise tests in 11 control subjects (26.9+/-9.5 years, 61.4+/-12.4 kg, 167+/-10 cm), and 11 patients (29.8+/-10 years, 59.3+/-12.0 kg, 168+/-7 cm) referred for bilateral ISS: results are mean+/-standard deviation. Surgery was performed at two distinct times allowing to study the consequences of unilateral and bilateral sympathectomy to confirm whether a significant relative bradycardia was constant and dependent on the operated side.


RESULTS
For control subjects, test durations were 13.55+/-3.29, 14.09+/-4.01 and 13.00+/-3.26 min and heart rates were 187+/-7, 187+/-8 and 186+/-7 beats min(-1) at the first, second and third test, respectively. Although time to exhaustion was comparable to controls and unchanged between tests: 12.32+/-2.87, 12.3+/-2.90, 12.33+/-3.76 min, heart rate at maximum exercise decreased significantly from 176+/-16 to 164+/-15, and 148+/-15 beats min(-1), before, following unilateral and bilateral ISS, respectively. The operated side did not allow for the prediction of the effect of unilateral sympathectomy.


CONCLUSIONS
Patients should be informed of the exercise bradycardia resulting from ISS, although clinical tolerance seems excellent in endurance exercise. Contrary to previous reports at rest, during exercise no right-sided dominance was observed. These findings are consistent with reports of random distribution of sub-stellate cardiac fibres from anatomical studies.
Abraham
P
P
Department of Vascular Investigations and Sports Medicine, University Hospital, 49033 Angers cedex 01, France. explovasc@chu-angers.fr
Picquet
J
J
Bickert
S
S
Papon
X
X
Jousset
Y
Y
Saumet
J L
JL
Enon
B
B
D000328:Adult; D001919:Bradycardia / Q000209:etiology*; D005080:Exercise Test; D017079:Exercise Tolerance; D005260:Female; D007839:Functional Laterality; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D013233:Stellate Ganglion; D013562:Sympathectomy / Q000009:adverse effects* / Q000379:methods