Fate of the Stented Arterial Duct

Abstract

Background-The technical aspects of ductal stenting have been reported, but little is known of the fate of the duct after stent implantation. Methods and Results-Nineteen patients underwent stent implantation to maintain ductal patency. Eight had hypoplastic left heart (HLH) syndrome, 10 had pulmonary atresia, and 1 had tricuspid atresia. Median survival with HLH was 57 (12 to 907) days. Stent implantation was successful in all cases of HLH, but there were no long-term survivors. Two well-palliated infants died at transplantation. Median survival with duct-dependant pulmonary flow was 183 (0 to 1687) days, with 3 patients well at latest follow-up (56, 55, and 9 months, respectively). There were 2 operative deaths due to ductal spasm and 4 late deaths, 1 due to duct thrombosis, 1 due to chronic lung disease, and 2 of unknown cause. Stent implantation failed in 4 of the 11 cases. Assessment of endothelialization was possible in 13 cases; the stent was partially covered in 3 and fully endothelialized in all 10 cases assessed Ͼ8 weeks after implantation. In patients stented for inadequate pulmonary flow, ductal intimal hyperplasia occurred by 9 months in all 3 survivors but responded to repeated dilation. Conclusions-Ductal stenting cannot be recommended. In patients with HLH, it provides only short-term palliation even when combined with pulmonary artery banding. With duct-dependent pulmonary blood flow, the procedure carries high risk, and duration of palliation is poor. In patients with bilateral ducts and absent central pulmonary arteries, good palliation may be achieved, but repeated angioplasty is necessary to counteract intimal hyperplasia. (Circulation. 1999;99:2621-2625.)

Stenting the Ductus Arteriosus

“…Limited animal experience 9 indicates that severe neointimal proliferation occurs within 14 months of the implant. This finding agrees with those reported by Gibbs et al 8 We agree that the placement of stents in infants with ductus-dependent pulmonary blood flow anomalies is far more technically demanding than stenting in infants with ductus-dependant systemic blood flow lesions. For instance, the ductal anatomy in infants with ductusdependent pulmonary blood flow is longer, more tortuous, and more complex than the anatomy usually seen in HLHS patients.…”

“…Thus, it might frequently be necessary to implant multiple devices to cover all of the ductal tissue, and the diameter needed may not be the one that the stent was designed for. Therefore, we are in full agreement with the conclusion reached by Gibbs et al 8 : stenting the ductus in congenital cardiac malformations to ensure adequate pulmonary blood flow should not be universally attempted using the presently available technology. That is not to say that we should abandon further efforts at developing a safe, durable, nonsurgical, artificial, BlalockTaussig shunt.…”

“…The use of stents to maintain the patency of the ductus arteriosus in neonates with ductal-dependent systemic blood flow and infants with ductal-dependent pulmonary blood flow congenital anomalies, one of the subjects of the present report in Circulation, 8 is of particular interest. The authors of the present report have shown the courage and skills required of interventionists to develop the notion of a nonsurgical, artificial, Blalock-Taussig shunt.…”

“…It would be highly desirable if we could conquer the obstacles that face us at the present time, as reported by Gibbs et al 8 Ideally, a catheter-directed approach would provide a more natural distribution of blood flow to the pulmonary vasculature. It might avoid surgical injury to the pulmonary arteries, a complication known to increase the risk during further, more definitive surgery.…”

Nova bandagem ajustável das artérias pulmonares na Síndrome de Hipoplasia de Câmaras Esquerdas

“…However, fine adjustments of the amount of pulmonary blood flow, which is a critical issue, has proved to be a particularly difficult aspect of the procedure. This can be readily explained when it is recalled that Poiseuille's law predicts that blood flow is related to the fourth power of the radius of the vessel [9,10].…”