[Therapeutic effect of Cheatham-Platinum stent implantation for vessel stenosis associated with congenital heart disease in children and adolescents].

OBJECTIVE: Although NuMED Cheatham-Platinum (CP) stent was specifically designed to treat vascular obstructions associated with congenital heart disease (CHD), its application in pediatric patients is relatively uncommon, especially in the pulmonary artery stenosis. The aim of this study was to evaluate the immediate-, early- and intermediate-term results of CP stent implantation in the treatment of vessel stenosis associated with CHD in children and adolescents. METHODS: From August 2005 to May 2007, 5 consecutive patients (3 boys and 2 girls) diagnosed as vascular stenosis associated with CHD underwent CP stent implantation in our institution. One patient had native coarctation of the aorta (CoA) and four patients had pulmonary artery stenosis. The median age and weight of patients were 12 years (range 4 - 15 years) and 24 kg (range 20 - 51 kg), respectively. The CP stent and NuMED Balloon-in-Balloon catheter were selected according to digital subtracted angiography measurements. After checking for correct position by angiography, the inner balloon and outer balloon inflated successively to expand the stent to desired diameter. RESULTS: Totally 6 stent placement procedures were performed and 8 CP stents (8-zig, 22 - 39 mm in length) were implanted in these 5 patients. All stents but one in a case of right pulmonary artery stenosis were immediately successfully placed in the target lesions without displacement during the procedures. For this case, a repeat procedure was performed and a second CP stent was reimplanted successfully 11 months later. After the procedure, the systolic pressure gradient across the stenosis decreased from (43.43 +/- 25.61) mm Hg (1 mm Hg = 0.133 kPa) to (3.29 +/- 3.09) mm Hg (t = 4.320, P < 0.01) and the narrowest diameter of the stenotic vessels increased from (6.86 +/- 2.04) mm to (13.44 +/- 4.02) mm (t = -4.508, P < 0.01). The percentage of pulmonary artery flow to the ipsilateral lung increased from 11.0% and 13.0% to 47.5% and 52.2% after the procedure in 2 cases of unilateral pulmonary artery branch stenosis, respectively. The ratio of right ventricular to aortic systolic pressure decreased from 62.3% and 72.2% to 27.0% and 33.3% in 2 cases of bilateral branch pulmonary artery stenosis, respectively. Upper limb blood pressure of one case of native CoA dropped greatly from 206/133 mm Hg to 156/95 mm Hg. During a median follow-up of 20 months (range 13 - 34 months), the results have been stable without complications except 2 stents which developed intrastent restenosis 6 months after the procedure. CONCLUSION: Our experience suggests that the CP stent implantation is safe and feasible for the treatment of vessel stenosis associated with CHD in children and adolescents. The immediate-, early- and interim results are encouraging, but long-term results remain to be further evaluated and demand many more cases to be studied.