Felipe David Gómez

Results of Stenting for Aortic Coarctation

Thisstudy reports the results obtained with stent implanta-tion in young and adult patients with AC.•••Between September 1996 and August 2000, 56stents were implanted in 54 patients with AC (35male, 19 female; age range 8 to 49 years, mean 22 69). AC was defined as a stenosis with a peak-to-peakgradient of

Balloon angioplasty in aortic coarctation: a multicentric study in Mexico.

20 mm Hg at rest. Fourteen patients hadassociated malformations: subaortic stenosis (2), ven-tricular septal defect (2), patent ductus arteriosus (1),coronary disease (2), and aortic valve disease (7). Fourpatients had undergone balloon angioplasty 2.5 to 7years before the study. Two had restenosis and 2 hadsmall saccular dilations. One case had surgical end-to-end repair with restenosis. All patients had local-ized AC, but 1 had a long tubular stenosis. Clinicalsuccess was defined as a peak-to-peak pressure gradi-ent of #20 mm Hg after stenting with no majorcomplications. Technical success was defined as suc-cessful stent deployment without complications. Clin-ical and Doppler examinations were performed at 1month and every 6 months. Pressure gradients beforeand after stenting were compared using Student’s t test(paired, 2-tail). A p value of ,0.05 was consideredsignificant.All cases were sedated. Antibiotic prophylaxis wasnot used. After arterial access, all patients received100 U/kg of heparin. Activated clotting time valueswere not measured. Gradient and arch angiographywere assessed. We used 55 Johnson & Johnson stents(41 P-308, 12 P-4014, and 2 P-5014, Warren, NewJersey) and one 60-mm-long Wallstent (Boston Sci-entific Corporation, Natick, Massachusetts). Stentswere selected for the diameter of the proximal aorta.The Wallstent was used for a long stenosis. Predila-tion was performed in only 3 patients. A stiff Amplatzguidewire was used with a 80-cm-long transseptal 9Frsheath (Cook, Bloomington, Indiana) with a P-308stent, or a 11Fr sheath with the P-4014 or P-5014stents. A dilator with a sheath was advanced across theAC. The dilator was removed, leaving the sheath andwire. Afterward, the stent was manually crimped on aballoon with a balloon-to-isthmus ratio of approxi-mately 1.0 to 1.2. Maximum balloon size was 25 mm.The stent was advanced to the stenosis and the sheathwas withdrawn, exposing the stent. The balloon wasinflated to 3 to 6 atm using a 20-ml inflator. Pressuresand angiography were repeated. Heparin was restarted4 hours after sheath removal and infused for 24 hours.Postprocedure heparin infusions were used to mini-mize femoral thrombotic complications, not for stentanticoagulation.Successful deployment was achieved in 53 patients(98%). Fifty-two patients (96%) had clinical success.The 1 failure was due to a residual gradient of 30 mmHg after stenting for restenosis after prior surgicalrepair. Although no high-pressure balloon was avail-able to us, there was no fluoroscopic calcification ofthe AC. This patient underwent a successful reopera-tion. Mean pressure gradient significantly decreased,from 50 6 20 mm Hg (range 11 to 110) to 5 6 8mmHg (range 0 to 30, p ,0.001). In 29 patients there wasno gradient after stent placement (Figure 1). In thepatient with long tubular AC (17 years old, 57 kg), thestenotic site was predilated with an 8-mm balloon toplace a Wallstent (16 3 60 mm length). The stent didnot totally expand, moving to the distal side of the AC.It was thus necessary to place a P-308 stent, whichresulted in expansion of the Wallstent. Fourteenmonths later, a small aneurysm was seen around theWallstent. The aneurysm did not involve the stentends, and may have been due to overdilation of theballoon (Figure 2). Magnetic resonance imagesshowed no growth of the aneurysm 9 months later. Inthe 2 cases in which an aneurysm occurred afterprevious balloon angioplasty, stent implantation wasenough to resolve the problem (Figure 3).One patient experienced vagal bradycardia thatrequired atropine. Two patients had paradoxical hy-pertension immediately after positioning the stent,which was treated with oral bblockers for 3 weeks. In1 case the stent was not delivered because ballooninflation moved the stent distally before the stentexpanded. In this patient, the stent was trapped in thefemoral artery when pulled back to the sheath. It wasremoved by surgery a few days later, and the AC wassurgically corrected.Two cases had stent migration during balloon in-flation. In the first, the stent deployed 2 mm below theAC site. There was complete resolution of the AC asa result of the balloon dilation and nothing further wasdone. This patient developed an aneurysm of the un-stented site. In the second patient, we implanted asecond stent to cover the dilation site after the firststent moved distally. There were no cases where bal-loon rupture caused stent migration.