Pulmonary artery stent implantation in children with single ventricle malformation before and after completion of partial and total cavopulmonary connections.

OBJECTIVES

Relief of pulmonary artery stenosis before and after cavopulmonary connections (CPC) in patients with single ventricle malformation is essential to optimize pulmonary hemodynamics. We evaluated the risk factors for pulmonary artery stenosis and assessed the outcome after stent implantation.

INTERVENTIONS

Seventeen stents in twelve patients were implanted for pulmonary artery stenosis before and after CPC at a mean age of 4.5 (0.1-17.6) years.

RESULTS

Fourteen stents were placed in the left pulmonary artery (82%) and three stents in the right pulmonary artery (18%). One stent was implanted intraoperatively. Mean time between surgery and stent implantation was 28 (1-132) months. The mean (SD) size of the pulmonary artery stenosis was 3.1 +/- 2.1 mm before and 8.1 +/- 3.3 mm (P < 0.001) after stent implantation. Six out of seventeen stents (35.2%) had to be redilated after a mean time interval of 19 (5-48) months. Two patients' stents were removed during the next surgical procedure; both needed an early restenting of the affected vessel. There were no procedure-related complications for stent implantation or redilatation. Anatomical risk factors for pulmonary artery stenosis were right aortic arch and hypoplastic pulmonary arteries, whereas dilatation of the ascending aorta for LPA stenosis and Blalock-Taussig shunt for RPA stenosis were surgical risk factors.

CONCLUSIONS

Stent implantation to treat pulmonary artery stenosis in pediatric patients with CPC is effective and can be realized safely. Close follow-up is recommended in patients with risk for pulmonary artery stenosis. During total cavopulmonary connection, previously implanted stents at that site should be left in place or be changed in a hybrid procedure to a larger diameter, because the etiology of stenosis may persist after surgery and the surgical removal could result in vessel injury that promotes restenosis.