Effects of movement and work load in patients with congenital central hypoventilation syndrome.
BACKGROUND
Patients with congenital central hypoventilation syndrome lack ventilatory chemosensitivity and depend at least in part on the ergoreceptor function during exercise. In these patients a substantial increase of ventilation has been reported for passive movement during sleep as well as active movement on a treadmill.


OBJECTIVE
The aim of the study was to investigate ventilatory response to an increasing work load with constant movement.


RESULTS
Eighteen patients and 17 healthy volunteers performed a cardiopulmonary exercise test on a bicycle pedaling at a constant rate of about 60 revolutions per minute throughout the entire test. The patients were able to exercise adequately and showed normal peak oxygen uptake. There was a steep rise in minute ventilation in both groups at the start of exercise, yet there was only a minor increase in both groups during the increase of workload up to the anaerobic threshold. After the anaerobic threshold, there was again an increase in ventilation in both groups, but the increase was less prominent in the patient group.


CONCLUSIONS
Ventilation in patients with congenital central hypoventilation syndrome is increased during exercise caused both by movement (mechanoreceptors) and by anaerobic workload. This facilitates a normal ventilatory drive up to the anaerobic threshold and a normal exercise capacity in these patients.
Hager
Alfred
A
Department of Pediatric Cardiology and Congenital Heart Disease, German Heart Center Munich, Technical University of Munich, Munich, Germany. a-hager@web.de
Koch
Walter
W
Stenzel
Heike
H
Hess
John
J
Schöber
Johannes
J
D000293:Adolescent; D015308:Anaerobic Threshold; D016022:Case-Control Studies; D002648:Child; D005080:Exercise Test; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009068:Movement; D005082:Physical Exertion; D012119:Respiration; D020182:Sleep Apnea, Central / Q000151:congenital* / Q000503:physiopathology*; D013990:Tidal Volume