Clinical Impact of Residual Shunts after Septal Defect Closure: Do Small Residual Defects under 2 mm Really Matter?

Objectives: Surgery for septal defect repair is a common low-risk procedure. Reports about residual septal defects (RSD) are rare, although RSD seem to be common. We retrospectively analyzed pediatric patients that underwent surgery to repair septal defects in our center with focus on RSD, RSD-related complications, and their impact on repeated intervention.

Methods: Data of 611 pediatric patients who had surgery to repair a variety of atrial and/or ventricular septal defects were retrospectively analyzed. Ostium primum defect (ASD I) (n = 73), ostium secundum defect (ASD II) (n = 182), partial anomalous pulmonary vein connection (PAPVC) with or without sinus venosus defect (n = 85), ventricular septal defect (VSD) (n = 115), Fallot (TOF) (n = 75) and complete atrioventricular septal defect (cAVSD) (n = 81) were repaired. Transthoracic echocardiography (TTE) was performed daily during intensive care stay, short before discharge and in routine follow-up.

Result: The overall incidence of RSD seen at discharge was 6.87% (n = 42). The incidence was significantly higher in patients with any kind of VSD (13.6%, 37/271) and very low in patients with any kind of ASD (1.47%, 5/340). From the five patients with atrial RSD (all ASD II) two patients had to be reoperated during the same hospital stay because of a hemodynamic relevant RSD. In the other three patients, spontaneous closure of RSD was reported in TTE within the first three postoperative months. Among 81 patients with cAVSD one patient (1.2%) needed reoperation during hospital stay due to a large ventricular RSD. At discharge 28% of the patients (23/81) presented with small ventricular RSD < 2 mm. None of the RSD was hemodynamically relevant. In follow-up (cAVSD patients) the incidence, due to spontaneous closure, reduced to 11%. After TOF-repair only one patient was reported to have a ventricular RSD of 2 mm at discharge and it was reported as closed in the cardiologist follow-up 14 months after surgery. The incidence of ventricular RSD at discharge, after isolated VSD closure, was 10.4%. Two years after, all residual defects, except from two patients with Swiss cheese VSD, were reported from cardiologist as closed. There were no reported complications relevant to a residual defect like endocarditis, valve tear, etc.

Conclusion: Atrial RSD are very rare (1.47%). Ventricular RSD are more common (13.6%) especially in the repair of CAVSD. Except from rare cases of reoperation because of a hemodynamic relevant RSD, there were no other implications throughout the follow-up. The vast majority of RSD <2 mm closes within the first 2 years after the operation.

No conflict of interest has been declared by the author(s).

Publication History

Article published online:
19 February 2021