Background: Six minute walk test (6MWT) is one of the most widely used tests to assess the functional capacity of a patient especially those with cardiopulmonary disease. Most of the studies on 6MWT were performed among adult patients. This study focused on the correlation of the hemodynamic parameters such as the arterial blood gas and pulmonary artery pressure with the six minute walk test particularly in a group of pediatric patients with congenital acyanotic heart disease.
Methods: We prospectively studied patients with congenital acyanotic heart disease with pulmonary arterial hypertension. All subjects had 2D Echo to determine pulmonary arterial pressure (PAP), arterial blood gas (ABG) analysis, 6MWT and Borg scale. We also classified them using the WHO functional classification for patients with pulmonary hypertension at the begging of the study.
Results: A total of 30 patients were enrolled in the study. Patients were classified in the WHO functional class I and II. No correlation was seen between ABG parameters and distance (all p value>0.05). A higher proportion of patients in WHO class II severe pulmonary hypertension compared to class I but was not significant (p 0.64). No correlation was found with the severity of pulmonary hypertension and 6MWT distance.
Conclusion: No correlation noted with ABG, pulmonary pressure and distance walked in the 6MWT.
Keywords: 6 minute walk test; congenital heart disease; arterial blood gas; pulmonary areterial pressure
Abbreviations: ABG = arteial blood gas; PAP = pulmonary arterial pressure; 6minute walk test = six minute walk test; PAH = pulmonary arterial hypertension