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Experience of stent implantation for recurrent aortic arch obstruction following Norwood or Damus–Kaye–Stansel operation over the last decade

Abstract Background: Recurrent aortic arch obstruction following the Norwood procedure is recognised as an important complication. Balloon arch angioplasty is associated with a high recoarctation rate. Methods: We sought to evaluate the prevalence and outcome of stent implantation for recoarctation in children following Norwood or Damus–Kaye–Stansel procedure over the past decade at a single national cardiology centre. Results: Of 114 children who underwent Norwood procedure or Damus–Kaye–Stansel procedure between January 2003 and June 2013, 80 patients survived. Of these 15 children underwent stent implantation for recoarctation. Six of these patients had previous balloon angioplasty. The median age at stent implantation was 4.4 months (range 2–82 months). The median peak aortic arch gradient at catheterisation decreased from 26mmHg (range 10–70mmHg) to 2mmHg (range 0–20mmHg). The median luminal diameter increased from 4.7 mm (range 3.2–7.9 mm) to 8.6 mm (range 6.2–10.9 mm). The median coarctation index increased by 0.49 (range = 0.24–0.64). A Valeo stent was employed in 11 children, a Palmaz Genesis stent in 2 patients, a MultiLink stent in 1 child, and a Jomed covered stent in 1 child. Two factors were associated with the need for stent placement: previous arch angioplasty (p valve < 0.001, χ-square 11.5) and borderline left ventricle (p = 0.04, χ-square = 4.1). Stent migration occurred in one child. There were two deaths related to poor right ventricular systolic function and severe tricuspid regurgitation. Six patients underwent redilation of the stent with no complications. Conclusions: The prevalence of recurrent aortic arch obstruction following Norwood/Damus–Kaye–Stansel procedure was 18%. Stent implantation is safe and reliably eliminates the aortic obstruction. Redilation can be successfully achieved to accommodate somatic growth or development of stent recoarctation.