Cardiopulmonary exercise test (CPET) has been gaining importance as a method of functional assessment in Brazil and worldwide. In its most frequent applications, CPET consists in applying a gradually increasing intensity exercise until exhaustion or until the appearance of limiting symptoms and/or signs. The following parameters are measured: ventilation; oxygen consumption (VO2); carbon dioxide production (VCO2); and the other variables of conventional exercise testing. In addition, in specific situations, pulse oximetry and flow-volume loops during and after exertion are measured. The CPET provides joint data analysis that allows complete assessment of the cardiovascular, respiratory, muscular and metabolic systems during exertion, being considered gold standard for cardiorespiratory functional assessment.1-6The CPET allows defining mechanisms related to low functional capacity that can cause symptoms, such as dyspnea, and correlate them with changes in the cardiovascular, pulmonary and skeletal muscle systems. Furthermore, it can be used to provide the prognostic assessment of patients with heart or lung diseases, and in the preoperative period, in addition to aiding in a more careful exercise prescription to healthy subjects, athletes and patients with heart or lung diseases.Similarly to CPET clinical use, its research also increases, with the publication of several scientific contributions from Brazilian researchers in high-impact journals.Therefore, this study aimed at providing a comprehensive review on the applicability of CPET to different clinical situations, in addition to serving as a practical guide for the interpretation of that test.

Nota: These guidelines are for information purposes and should not replace the clinical judgment of a physician, who must ultimately determine the appropriate treatment for each patient.

Background: Oxygen-uptake efficiency slope (OUES) is an objective measure of functional capacity that does not require a maximal effort but is considerably dependent on anthropometric variables and requires the generation of an appropriate reference value in children. This study aimed to establish normal reference values for OUES/kg in children with and without congenital heart diseases. Besides that, reference values are presented secondarily for OUES per body surface area (OUES/BSA). Design: Cross-sectional. Methods: Six hundred and seventy-six children and adolescents performed a maximal cardiopulmonary exercise test (305 healthy controls and 371 individuals with congenital heart defect), between four and 21 years old (481 males and 195 females, with a mean age of 12 years). Results: The OUES reference value for the classification of children and adolescents with normal functional capacity (>80% of predicted maximum oxygen uptake) was 34.63 (sensitivity 77% and specificity 83%, p < 0.05). Regarding the body surface area, considering healthy patients and those with heart disease, the cutoff value of the OUES/BSA was 1151 with sensitivity of 79% and specificity of 79%. Conclusions: OUES/kg may be an important marker tool in the differentiation between preserved or abnormal functional capacity in children and adolescents with and without congenital heart disease, even at the submaximal level of exercise.

Our results showed that exercise capacity long-term after ASO in TGA is well preserved although lower than in healthy children what might be explained by the presence of chronotropic incompetence in the TGA group.