[Cardiopulmonary exercise testing in patients with pectus excavatum]. / Exploration fonctionnelle à l'exercice des patients présentant un pectus excavatum.

ABSTRACT

The functional consequences of physiologic impairments due to pectus excavatum (PE) are not known. This study was conducted to determine the exercise performance in patients with this condition. This prospective study included all patients presenting for PE during a 5-year period. Patients had a chest CT scan to measure the PE severity index, resting pulmonary function tests, cardiopulmonary exercise testing (CPET) with gas exchange analysis and echocardiography. Thirty-two patients were included, with a mean age of 25.9 years. The mean PE severity index was 3.72 ± 0.87. The maximal oxygen uptake (VO(2-max)) was 78.6 ± 22.1% predicted. Only four out of the 32 patients had a normal CPET. In the remaining patients, we observed three main patterns of limitation: 18 patients had a marked limitation in increasing their tidal volume (41 ± 5% of FVC at VO(2-max) versus 51 ± 7.5%); five patients had abnormal gas exchange with increased P(A-a)O(2) at VO(2-max) (47 ± 23 mmHg versus 20 ± 7.5 mmHg) associated with a patent foramen ovale without elevation of right pressure. The five last patients had cardiovascular impairment with a decreased oxygen pulse at VO(2-max) (57 ± 9% versus 90 ± 20%). They exhibited the most severe limitation (VO(2-max) = 55 ± 10%; P = 0.003). CPET abnormalities were predicted by neither PE index severity nor the results of resting pulmonary function tests. PE is associated with abnormal CPET, including impairments in ventilatory, cardiovascular responses and/or gas exchange, which may be of importance in disease management.