Follow-up
Patients were followed up by routine echocardiography. Computed tomography examinations were performed when necessary. Cardiac catheterization was performed in patients with >20 mmHg echocardiographic gradients (with diastolic extension) and patients with gradient  >20 mmHg between upper and lower extremity arterial  pressures. During cardiac catheterization, >10 mmHg gradient for single ventricle patients and  >20 mmHg gradient for double ventricle patients were considered as indications for  reintervention. However, the decision to conduct a reintervention was made by the patient’s treating physicians based on the overall clinical picture. Patients with a significant gradient underwent reintervention by catheter balloon angioplasty and surgical intervention was performed if this was not sufficient or not suitable.