Ultraflex stents for the management of airway complications in lung transplant recipients

Abstract

Respirology 2003;8:59–64. Chhajed PN, Malouf MA, Tamm M, Glanville AR. Comments: In this study, Chhajed and coworkers report their experience with the use of an uncovered Ultraflex (nitinol) stent in the management of airway stenosis in 9 lung transplant recipients. The indications for stent placement were stenosis of the large airway in 4 patients, combined stenosis and bronchomalacia in 3 patients, and tracheomalacia and bronchomalacia in 1 patient each. A total of 11 stents were deployed in 9 patients. Stents were placed using a flexible bronchoscope with fluoroscopy guidance under conscious sedation. Proximal release stents were used in 6 patients and distal release stents in 3 patients. The mean ± standard deviation increase in forced expiratory volume in 1 second (FEV1) after insertion of the procedure was 522 ± 391 mL (range, 120–1150 mL). Successful stent deployment led to improvement in dyspnea in all patients. In 2 patients, initial placement of the stent was unsatisfactory as a result of proximal displacement of the stent delivery device. This problem occurred with the proximal release stent delivery device in both cases. Stricture resulting from excessive growth of granulation tissue formed in 1 patient, and it was treated with balloon dilatation and laser resection. Stent migrated in 1 patient from its original position, and it had to be removed. No patient developed stenosis at the stent extremities or mucus plugging during the follow-up period of 263 ± 278 days after the procedure. Airway complications are common after lung transplantation. Common complications include anastomotic stenosis, bronchomalacia, or a combination of stenosis and malacia, granulation tissue, and anastomosis dehiscence. The majority of patients with symptomatic airway stenosis after lung transplantation require interventional bronchoscopic treatment (Chest 2001;120:1894–9). The choice of treatment depends on endoscopic findings. For stenosis, balloon dilatation is the first-line treatment. However, despite its high initial success, the majority of patients eventually require airway stent as a result of recurrence of stenosis or as a result of development of bronchomalacia. There is no single ideal stent for this purpose. Recent reports indicate successful deployment of self-expandable metal stents in these patients. Uncovered wall stents have been considered more suitable than prior designs of metallic stents (such as Gianturco and Palmaz stents) for this purpose. However, in a prior study, Chhajed and coworkers reported granulation tissue and mucus plugging in 27% patients each after placement of uncovered wall stents in lung transplant recipients (Chest 2001;120:1894–9). The present study by Chhajed and coworkers suggests that the Ultraflex stent could be better than uncovered wall stents for managing airway stenosis after lung transplantation as a result of the very low risk of secretion accumulation, mucus plugging, and development of granulation tissue at the ends of the stent. Although the sample size was small, the results indicate that the Ultraflex stent is presently the most useful metal stent for management of airway stenosis in lung transplant recipients.