The BNP concentrations and exercise capacity assessment with cardiopulmonary stress test in patients after surgical repair of Fallot's tetralogy

Adult patients after surgical repair of Fallot's tetralogy usually present with satisfactory exercise capacity years after the original procedure, though they never tolerate as high levels of exercise as their healthy counterparts. The aim of the study was to assess exercise capacity with cardiopulmonary stress test and BNP levels in adult survivors of surgical repair of Fallot's tetralogy. We studied 60 patients with no or only mild symptoms (including 29 males), at the mean age of 27.6 ± 8.2 years at the time of follow-up screening, operated on at the age of 7.5 ± 5.3 years. In 34 patients moderate to severe pulmonary regurgitation (PR+) was observed. Control group consisted of 28 healthy volunteers (13 males), aged 28.7 ± 5.1 years. Peak oxygen uptake (VO2) in studied group was found to be significantly lower than in control group (24.7 ± 5.5 vs. 36.6 ± 7.6 ml/kg/min, p = 0.00001), VE/VCO2 slope, the marker of respiratory effort, was higher in surgical treatment group as compared to the control group (36.5 ± 6.3 vs. 29.7 ± 4.7, p = 0.004). In patients with PR+, peak VO2% was higher than in PR− individuals (69.6 ± 11.8% vs. 58.5 ± 12.1%, p = 0.0005). The BNP concentration in the studied group (34.8 ± 27.1 pg/ml) was higher than in healthy subjects (11.5 ± 6.5 pg/ml, p = 0.00001). Levels of BNP correlated inversely with peak VO2 (r = − 0.286, p = 0.03), FVC (r = − 0.265 p = 0.04) and positively with VE/VCO2 (r = 0.361, p = 0.005). Additionally the levels of BNP correlated positively with the age of patients at the time of surgical repair (r = 0.250, p = 0.04). We concluded that exercise capacity in adults after repair of Fallot's tetralogy, especially those PR+, was lower than in healthy volunteers. Concentrations of BNP in surgical treatment survivors were higher and correlated well with cardiopulmonary stress study parameters.