Pediatric Cardiology and Cardiac Surgery
Vol.26 No.4 2010 (310-316)

Yumi Koike, Satoshi Yasukochi, Kiyohiro Takigiku, Ichige Kajimura, Satoshi Matsuzaki, Kohta Takei, and Gengi Satomi

Department of Cardiology, Nagano Children’s Hospital, Nagano, Japan


Background: While many reports describe the clinical usefulness of stent dilation of the pulmonary artery stenosis, only a few have evaluated the expandability or redilation feasibility of implanted stents within pulmonary vasculature that became stenotic again.
Patients and methods: Ten patients, age 1 to 14 (mean 7) years and weight 8.2 to 36.7 (mean 23) kg, underwent redilation of implanted stents in the pulmonary arteries either by balloon or additional stent-in-stent. Redilation procedures were performed 3 to 29 months (mean 21) after the original stent insertion. We measured the intraluminal diameters of the restenotic sites, originally implanted stents, and intact pulmonary arteries just distal to the stents as reference, before and immediately after redilation procedures. Expandability was calculated as the ratio of diameters before and after redilation.
Results: The reference diameter grew from 6.6±3.2 to 8.0±2.6 mm (119±23%). Therefore, appropriate sizes of balloon were employed. After the redilation procedure, the minimal intraluminal diameter at the restenotic site increased from 6.0±3.2 to 8.5±2.6 mm, making expandability 145±41% and the stent diameters from 7.7±3.2 to 9.5±2.6 mm (132±23%). No migration of the original stents was noted, but one stent fracture occurred after the procedure. Another case suffered a controllable pulmonary hemorrhage caused by a guide wire.
Conclusion: Redilation of the implanted stents with restenosis in the pulmonary arteries can be safely performed and achieves good results.