Is the six-minute walk test still reliable compared to cardiopulmonary exercise test for exercise capacity in children with congenital heart disease?

Abstract

ObjectivesWe aimed to assess the validity of the six-minute walk test (6MWT) to reflect the functional capacity of children with congenital heart disease (CHD), evaluate a possible correlation between the 6MWT distance with cardiopulmonary exercise test (CPET) variables, as well as to find a cutoff value to stratification the physical fitness in this population.MethodsWe enrolled 459 children with CHD, 6–18 years old, who performed a complete CPET and 6MWT on the same day in a cross-sectional observational study. Correlations between variables of CPET and six-minute walking distance (6MWD) were analyzed and cutoff values of 6MWD were identified for the classification of the physical fitness in the population.ResultsThe mean distance ambulated during the 6MWT was 578 ± 65 m, 590 ± 65 m for boys, and 562 ± 62 m for girls (p < 0.001). Both VO2max and %predicted VO2max showed a correlation with the 6MWT distance (r = 0.35, p < 0.001 and r = 0.51, p < 0.001, respectively), and an inverse correlation was found between VE/VCO2 slope and the 6MWT distance (r = −0.31; p < 0.001). There appeared to be a linear association between 6MWD and VO2max up to a 6MWD of approximately 600 m. We divided the population into 4 subgroups (boys <130 cm; boys ≥130 cm; girls <130 cm; girls ≥130 cm), and get the cutoff values (554 m, 617 m, 549 m, 587 m) respectively equivalent to 80% of predicted VO2max. The 6MWT distances of another 102 patients were applied for external verification of the cutoff values.ConclusionsOur study provided evidence on when a 6MWT should be considered as a convincing complementary test in the pediatric population with CHD and explored the classification of exercise tolerance using a 6MWD value. The cut-off values for 6MWD may be qualified as an intervention target for exercise rehabilitation.

Ergospirometric testing: a modern approach to the diagnosis of physical health

“…These findings may be due to particular group or due to more stress associated with ergospirometric testing like treadmill [40]. In addition, another study conducted to evaluate the accuracy of the six-minute walk test in children with congenital heart disease determined specific values that can be used to categorize physical fitness and found connections with variables from the cardiopulmonary exercise test stressing on the use of the traditional testing like 6-minute walk testing as compared to treadmill Ergospirometric testing [41]. In addition, a cross-sectional study was conducted to compare the performance of obese/overweight children and normal-weight children in the 6-minute walk test and their hemodynamic parameters and found that OW&OB children had lower performance and experienced higher hemodynamic stress and, in this way, highlighting the significance of early intervention in order to reduce future health risks using more latest Ergospirometric testing [42].…”