Cardiopulmonary Exercise Testing: Reference Values in Adolescent and Adult Patients with Congenital Heart Diseases

pp. 99-104

Abstract

Background: The interpretation of cardiopulmonary exercise testing (CPET) in congenital heart diseases represents a challenge, since they constitute a large group of anomalies with different degrees of severity.

Objectives: The aim of this study was to obtain reference values of CPET variables in adolescents and adults with congenital heart diseases in our center, to compare between peers the expected results of CPET according to age, gender and the same pathology.

Methods: A total of 799 tests were performed in 473 patients older than 17 years with different congenital heart diseases. Variables studied were peak VO2 (ml/kg/min), percent-predicted peak VO2, test duration in seconds (discriminated by gender), VE/VCO2 slope and R coefficient for all the tests. Statistical analyses were conducted using mean and standard deviation for each variable and Student’s t test for those studied by gender.

Results: Peak VO2 (ml/kg/min), percent-predicted peak VO2, and test duration decreased as the severity of heart diseases increased. The percent-predicted peak VO2 corrects VO2 ml/kg/min values for age and sex, so it becomes a more useful variable for evaluation. An R coefficient greater than 1.1 indicates that patients performed a maximal test. The VE/VCO2 slope is increased in severe heart diseases.

Conclusions: Reference CPET values for the different congenital heart diseases are essential, since they allow us to compare patients with the same pathology. The percent-predicted peak VO2 seems to be the most useful variable for this purpose.