Late neointimal proliferation following implantation of stents for relief of pulmonary arterial stenosis

Successful dilatation of left pulmonary artery stenosis by stent implantation through a modified Blalock-Taussig shunt in an infant with pulmonary atresia and ventricular septal defect

We successfully implanted a coronary stent via a modified Blalock-Taussig shunt to relieve stenosis of the left pulmonary artery in an infant with pulmonary atresia and ventricular septal defect. The placement of a flexible coronary stent via a modified Blalock-Taussig shunt is a safe and feasible catheter intervention for the treatment of infants with hypoplastic pulmonary arteries.

Stent implantation and subsequent dilatation for pulmonary vein stenosis in pediatric patients: maximizing effectiveness

The outcome of stent implantation and redilatation was investigated in 4 pediatric patients with 7 stenotic lesions of the pulmonary vein (PV), paying particular attention to late neointimal proliferation. The minimal diameter of the lesions increased from 0.8-3.6 (2.3+/-1.1) mm to 3.6-8.4 (5.1+/-1.6) mm immediately after stent implantation. Although the pressure gradient across the lesion was not measured in patient 4, in patients 1-3, it decreased from 4-34 (18+/-13) mmHg to 3-15 (7+/-4) mmHg. Except for case 4, who achieved a lesion diameter of 8.4 mm after initial stent dilatation, the other 6 lesions all restenosed within a few months, with an increasing pressure gradient. One patient with multiple PV stenoses associated with persistent severe pulmonary hypertension died suddenly. However, repeat dilatations were effective in all other lesions. Furthermore, in one lesion in patient 1, no serious restenosis developed for 20 months after the lesion was dilated up to 5.6 mm. Although further follow-up is mandatory, the final stent diameter within a vessel may determine long-term patency, and aggressive redilatation may be crucial for successful therapy of such a difficult disease.