Neurally adjusted ventilatory assist (NAVA) is a new mode of mechanical ventilation that delivers ventilatory assist in proportion to neural effort. It was a controlled randomized single-center prospective study in order to explore the efficacy of this new mode of mechanical ventilation after corrective open-heart surgery for congenital heart disease.

1. To evaluate the effect of the patient-ventilator interaction in children underwent open-heart surgery when ventilated with NAVA, compared with conventional mechanical ventilation.
2. To verify the benefits of NAVA in improving the gas exchange and hemodynamics after biventricle repair for CHD.

Inclusion Criteria:

• patients underwent cardiac surgery with biventricle repaired
• patients need mechanical ventilation more than 24hrs after cardiac surgery

Exclusion Criteria:

• age >18 years
• inappositely of catheter insertion
• hemodynamic instability
• coagulation disorders or bleeding
• inclusion in other research protocol