Is the coast clear for stent angioplasty of coarctation?

C oarctation and recoarctation of aorta have been treated successfully with endovascular therapy, including balloon angioplasty or stent angioplasty, for >3 decades. 1–4 After successful surgical repair reported by Craafoord and Nylin, 5 the concept of angioplasty in the coronary arteries reported by Gruntzig et al 6 opened up a new strategy of treatment of native and recoarctation. Balloon angioplasty was successful in relieving the obstruction, but the long-term results were disappointing, with the recurrence of obstruction and incidence of aneurysm formation in the earlier studies. 7,8 This was soon abandoned in infants and young children to make way for improved short-term and intermediate outcomes from surgery that included techniques such as end-to-end anastomosis, extended end-to-end anastomosis, subclavian flap repair, patch angioplasty, and interposition grafts for complex coarctation. 9 The basic principle of disruption of the aortic wall with a tear in the intima extending to the media remains the mechanism of relief of coarctation. 10 Over time, stent angioplasty became a natural progression of an endovascular interventional strategy. The stent, apart from reducing the risk of recoarcta-tion, also arguably reduces the risk of aneurysm formation by apposing the disrupted intima at the site of the coarctation. 11 With the advent of stent angioplasty, the material properties, designs, and advantages and disadvantages of stents became important topics for discussions, publications, and research. The balloon-expandable, stainless steel, slotted-tube stents were the first to be used as off-label devices in aorta when designed primarily for renal and peripheral interventions. 12 Although the short-term hemodynamic results were acceptable , the risk of aortic aneurysm formation, early or late, and of aortic disruption or rupture remained a major risk. In addition, at larger diameters, these stents shorten by >20%. The double-strut design was then considered to be a better design that would not shorten and would be flexible to go around curves. The strength of this design, however, was not good enough to withstand the compressive stresses. The Cheatham-Platinum (CP) stent has a unique design with platinum-iridium wires welded together rather than slotted stainless steel tubes. The rounded edges of these wires are less traumatic to the edges of the vessel that is stented. It was designed to be used in large vessels such as the aorta and to allow dilatation to larger dimensions with limited shortening. 11 Against this background, the accompanying report by Meadows and colleagues 13 in this issue of Circulation …