Symptomatic pectus deformities of the chest.

Aspects of pulmonary mechanics and exercise tolerance were investigated in 8 young male patients with pectus deformities, 5 of whom presented with the chief complaint of exercise limitation. Results of pulmonary mechanics studies did not adequately explain patient symptoms. Lung volumes were only mildly reduced. There was no evidence of airway obstruction. Measures of lung compliance were normal in 6 patients studied. Results of exercise studies did reveal significant abnormalities in symptomatic and asymptomatic patients; tidal volume at maximal effort expressed as a percentage of vital capacity was diminished, suggesting restriction of ventilation. Oxygen uptakes in the 4 symptomatic patients were normal at lesser work loads but progressively exceeded predicted values at greater work loads, suggesting an abnormally elevated work of breathing during vigorous exertion. Three asymptomatic patients demonstrated a normal linear pattern of increase in oxygen uptake with increasing work load. Respiratory symptoms in some patients with pectus deformities appear to have a physiologic basis. Our data suggest a dynamic restrictive pulmonary process as an explanation for these symptoms.