Improved cardiopulmonary exercise function after modified Nuss operation for pectus excavatum

OBJECTIVES: Patients with pectus excavatum have compromised cardiac function during exercise. We hypothesized that the Nuss technique would improve cardiopulmonary function during exercise.

METHODS: We investigated 75 teenagers (49 patients and 26 controls) at rest and during bicycle exercise prior to surgery and 1 year postoperative.

RESULTS: Prior to surgery, patients had a lower cardiac index 6.6 ± 1.1 l/min/m(2) when compared with controls 8.1 ± 1.0 l/min/m(2) during submaximal exercise, P = 0.0001. There was no difference in heart rate or increase in heart rate between the two groups. One year after surgery, cardiac index had significantly increased in the pectus group, P = 0.0054 although cardiac index was still significantly lower 7.2 ± 1.0 l/min/m(2) when compared with the control subjects (8.5 ± 1.6 l/min/m(2), P = 0.0008). Both the patients and the controls increased their VO(2) max during the one-year study period although the controls increased most. Right ventricular diastolic dimension increased in both groups over the one-year study period and left ventricular dimensions increased in the patients. Before operation, the patients had lower forced expiratory capacity FEV(1) 86 ± 13% when compared with controls 94 ± 10%, P = 0.009. Patients increased FEV(1)/forced vital capacity over the one-year long study course although there were no differences between groups.

CONCLUSION: Patients with pectus excavatum have lower cardiac index at submaximal exercise when compared with healthy age-matched controls. Their cardiac index and FEV(1) are increased one year after the modified Nuss operation.