Early and midterm outcomes of bare metal stenting in small children with recurrent aortic coarctation

Aims: The aim of this study was to report our experience with the Cook Formula stent in the treatment of (recurrent) coarctation of the aorta in children below 12 kg. Methods and results: In vitro study of the Cook Formula 418 (8 mm) and 535 (8 and 10 mm) stents demonstrated successful down-crimping on smaller balloons and predictable fracturing patterns. Between November 2012 and January 2019, one patient with native, one patient with post-interventional and thirteen patients with post-surgical coarctation of the aorta underwent implantation of a Cook Formula stent. Patient and procedural characteristics were obtained as well as procedural success, complications, and follow-up. Median age was 4.3 months and median weight 5.5 kg. Arterial sheath size ranged from 5 to 7 Fr. In-stent diameters of 3.7 to 8.8 mm were obtained with a median residual gradient of 0 mmHg. Major complications consisted of periprocedural haemodynamic instability (n=1), dissection of the iliac artery (n=1) and non-deployment with surgical removal (n=1). Re-dilations were performed after a median interval of 24.3 months. Median follow-up was 31.7 months. Conclusions: The bare metal Cook Formula stent provides a durable and effective alternative to reoperation and balloon dilatation for native as well as post-surgical aortic coarctation in children below 12 kg.