Not quite ready for prime time!

Abstract

Supravalvular aortic stenosis has been waiting in the wings for some therapeutic catheter intervention. Because of concerns about the proximity of the aortic leaflets and/or the coronary orifices to the area where an intravascular stent would be implanted, this lesion has not been considered applicable for intravascular stents by most interventional cardiologists. The patient in this case report is the third patient with supravalvular aortic stenosis reported by the group in Cordoba with the implant of intravascular stents in the supravalvular area. The first two patients were reported in 1996; they had no complications during the procedure [1] and presumably they are still doing well.The implant of the stent in the supravalvular area in the patient in this report was also ultimately successful and had a good outcome. However, it was only because of the very innovative and skillful, but at the same time perhaps somewhat fortuitous, actions by the operators that the result was not catastrophic.The temporary arrest of the heart with adenosine and the very selective simultaneous angiograms during the stent implant represent the maximum precautions available for the very precise and accurate positioning and implant of any intravascular stent. In spite of these precautions and implanting the stent exactly as planned, the leaflets of the aortic valve were trapped, held open between the expanded stent and the aortic wall, and resulted in massive aortic regurgitation.A technique for temporarily pulling part the stent away from the trapped leaflets without dislodging and/or removing the stent was carried out while the patient was being supported medically and prepared for immediate surgery. A loop of guidewire was passed through the end cells of the stent and grasped with a separate snare catheter catching the loose end of the wire. The end of the stent was then pulled partially away from the aortic wall (and the valve leaflets) with the snare catheter pulling on the grasping and pulling on the loop of the wire through the wires of the stent. This was all accomplished after the aortic leaflets became trapped and with the patient in near cardiovascular collapse.This very exciting recovery during the procedure apparently was not planned in advance, has never been described and/or tried previously, and, as a consequence, may or may not be effective again under the same circumstances. No matter how innovative the recovery procedure was during this particular procedure, it cannot be considered as a dependable bailout for releasing aortic leaflets trapped by a stent under the same circumstances until it is documented that this technique is repeatable and reliable. This technique hopefully could be tested in an experimental animal study and may be applicable for other malpositioned stent.In spite of the eventual good outcome for the patient in this report, the patient did have a potentially catastrophic complication during the procedure. With this complication, the authors who are the operators with the most experience at treati...

Stenting of the ascending aorta revisited

“…The only reported pediatric case of acquired ascending aorta stent placement is in a 15-year-old with transposition of the great vessels, post arterial switch operation [4]. Although, these authors share some of our conclusions, their patient had a bioprosthetic aortic valve, which they felt was somewhat protective for the valve cusps and coronary orifices.…”