Results of stenting for aortic coarctation.

E stents have been widely used in peripheral and coronary arteries, postsurgical stenosis of the pulmonary arteries, and in the superior vena cava and conduits in congenital heart diseases.1–8 Several reports support the use of balloon-expandable stents for aortic coarctation (AC) in humans.9–13 This study reports the results obtained with stent implantation in young and adult patients with AC. • • • Between September 1996 and August 2000, 56 stents were implanted in 54 patients with AC (35 male, 19 female; age range 8 to 49 years, mean 22 6 9). AC was defined as a stenosis with a peak-to-peak gradient of $20 mm Hg at rest. Fourteen patients had associated malformations: subaortic stenosis (2), ventricular septal defect (2), patent ductus arteriosus (1), coronary disease (2), and aortic valve disease (7). Four patients had undergone balloon angioplasty 2.5 to 7 years before the study. Two had restenosis and 2 had small saccular dilations. One case had surgical endto-end repair with restenosis. All patients had localized AC, but 1 had a long tubular stenosis. Clinical success was defined as a peak-to-peak pressure gradient of #20 mm Hg after stenting with no major complications. Technical success was defined as successful stent deployment without complications. Clinical and Doppler examinations were performed at 1 month and every 6 months. Pressure gradients before and after stenting were compared using Student’s t test (paired, 2-tail). A p value of ,0.05 was considered significant. All cases were sedated. Antibiotic prophylaxis was not used. After arterial access, all patients received 100 U/kg of heparin. Activated clotting time values were not measured. Gradient and arch angiography were assessed. We used 55 Johnson & Johnson stents (41 P-308, 12 P-4014, and 2 P-5014, Warren, New Jersey) and one 60-mm-long Wallstent (Boston Scientific Corporation, Natick, Massachusetts). Stents were selected for the diameter of the proximal aorta. The Wallstent was used for a long stenosis. Predilation was performed in only 3 patients. A stiff Amplatz guidewire was used with a 80-cm-long transseptal 9Fr sheath (Cook, Bloomington, Indiana) with a P-308 stent, or a 11Fr sheath with the P-4014 or P-5014 stents. A dilator with a sheath was advanced across the AC. The dilator was removed, leaving the sheath and wire. Afterward, the stent was manually crimped on a balloon with a balloon-to-isthmus ratio of approximately 1.0 to 1.2. Maximum balloon size was 25 mm. The stent was advanced to the stenosis and the sheath was withdrawn, exposing the stent. The balloon was inflated to 3 to 6 atm using a 20-ml inflator. Pressures and angiography were repeated. Heparin was restarted 4 hours after sheath removal and infused for 24 hours. Postprocedure heparin infusions were used to minimize femoral thrombotic complications, not for stent anticoagulation. 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 mm Hg after stenting for restenosis after prior surgical repair. Although no high-pressure balloon was available to us, there was no fluoroscopic calcification of the AC. This patient underwent a successful reoperation. Mean pressure gradient significantly decreased, from 50 6 20 mm Hg (range 11 to 110) to 5 6 8 mm Hg (range 0 to 30, p ,0.001). In 29 patients there was no gradient after stent placement (Figure 1). In the patient with long tubular AC (17 years old, 57 kg), the stenotic site was predilated with an 8-mm balloon to place a Wallstent (16 3 60 mm length). The stent did not totally expand, moving to the distal side of the AC. It was thus necessary to place a P-308 stent, which resulted in expansion of the Wallstent. Fourteen months later, a small aneurysm was seen around the Wallstent. The aneurysm did not involve the stent ends, and may have been due to overdilation of the balloon (Figure 2). Magnetic resonance images showed no growth of the aneurysm 9 months later. In the 2 cases in which an aneurysm occurred after previous balloon angioplasty, stent implantation was enough to resolve the problem (Figure 3). One patient experienced vagal bradycardia that required atropine. Two patients had paradoxical hypertension immediately after positioning the stent, which was treated with oral b blockers for 3 weeks. In 1 case the stent was not delivered because balloon inflation moved the stent distally before the stent expanded. In this patient, the stent was trapped in the femoral artery when pulled back to the sheath. It was removed by surgery a few days later, and the AC was surgically corrected. Two cases had stent migration during balloon inflation. In the first, the stent deployed 2 mm below the AC site. There was complete resolution of the AC as a result of the balloon dilation and nothing further was done. This patient developed an aneurysm of the unstented site. In the second patient, we implanted a second stent to cover the dilation site after the first stent moved distally. There were no cases where balloon rupture caused stent migration. From the Cardiology Hospital, National Medical Center 21st Century, Mexican Institute of Social Security, Mexico City, Mexico; and University of Chicago Hospitals, Chicago, Illinois. Dr. Ledesma’s address is: Privada de Corregidora #5, San Jerónimo Lı́dice. C.P. 10200, Mexico D.F. E-mail: [email protected]. Manuscript received December 4, 2000; revised manuscript received March 13, 2001.