Stent implantation for recurrent interatrial obstruction in an infant with hypoplastic left heart syndrome

Atrioventricular block following implantation of a stent in the oval fossa

A neonate weighing 2.8 kilograms underwent the staged hybrid procedure for palliation of hypoplastic left heart syndrome. Within 6 hours following placement of a stent to retain patency of the interatrial communication, the infant developed second degree atrioventricular block, which resolved within 24 hours. Four days later, the patient developed complete atrioventricular dissociation. Removal of the stent was followed by recovery of atrioventricular conduction.

Implantation of stents to ensure an adequate interatrial communication in patients with hypoplastic left heart syndrome

AIMS

To assess the feasibility of interatrial stenting for left atrial decompression in infants with hypoplastic left heart syndrome treated by a "hybrid-approach", with bilateral surgical banding of the pulmonary arteries and percutaneous stenting of the arterial duct.

PATIENTS AND METHODS

We stented the atrial septum in 5 infants aged from 21 to 77 days, making the intervention as an elective procedure in 4, but as a rescue procedure in the fifth patient, who had a restrictive foramen. The stents, comprising 2 Jo-stents of 17 millimetres hand-crimped on a balloon catheter with dimensions of 10 by 20 millimetres, and 3 premounted Genesis stents with dimensions of 10 by 19 millimetres, were placed using a 6 French long or short sheath by femoral venous access. The stents were expanded under fluoroscopic guidance to create a slightly diabolo-shaped form that fitted the septum.

RESULTS

The percutaneous interventions were successfully performed in all cases, producing significant improvement in clinical condition after placement. The saturations of oxygen increased from an average of 64% plus or minus 18% to 88% plus or minus 7%, (p < 0.05). During a mean follow up of 2.5 months, without any anticoagulant therapy, there were no complications related to the stenting. Surgical removal of the stents was uneventful during reconstruction of the aortic arch and creation of a bidirectional cavopulmonary connection in 4 patients, and during cardiac transplantation in one.

CONCLUSION

In the context of the hybrid approach, definitive decompression of the left atrium can be achieved by stenting the atrial septum in infants with hypoplastic left heart syndrome. Placement of the stents is safe and effective, with insertion in the form of a diabolo reducing the risk of dislocation, as well as embolisation of the stent.