title: Incidence and outcomes after infolding or collapse of thoracic stent grafts.
abstract: OBJECTIVE
  Device-related complications in the thoracic aorta are partly due to the unavoidable proximal angulation and increased flow-related forces. The present study evaluated the incidence, predictors, and outcome of the complication of infolding with the GORE TAG thoracic endoprosthesis (TAG device) to better understand the factors that might help predict these events.
  
  
  METHODS
  We reviewed all complaints reported to W. L. Gore and Associates (Flagstaff, Ariz) related to device infolding after the use of the GORE TAG device on or before December 2008. Events related to device infolding were evaluated. Reporting physicians and local company representatives were contacted, when necessary, to assemble all available imaging, data, and outcomes related to these case reports. When available, computed tomography images were reviewed to confirm aortic landing zone diameters, which were subsequently compared with the implanted device size.
  
  
  RESULTS
  From 1998 through December 2008, device infolding was reported in 139 patients (mean age, 40 ± 17 years; 73.4% men) from 33,289 device implants (reported incidence, 0.4%). Events were noted in implants for trauma (60%), dissection (19%), aneurysm (10%), and other (9%) and unknown (2%) etiologies. In 77 patients with available imaging, the average minimum aortic diameter was 21.4 ± 4.4 mm. The mean device diameter was 28.5 ± 3.5 mm, with an average oversizing of nearly 33%. Of reported patients, 51% were asymptomatic, with the diagnosis being made on routine chest imaging. Time to diagnosis was 76 ± 222 days (median, 9.5 days). Only 16 patients received no intervention after the diagnosis of device infolding, all of whom were asymptomatic. The other 123 patients underwent 135 interventions. Of these, 30 patients (24%) underwent open surgical conversion and complete or partial endograft removal. The other interventions included a variety of endovascular techniques, such as large balloon-expandable stent(s) in 40%, relining with additional endograft(s) in 31%, and repeat ballooning in seven patients. Ten patients died after device infolding, all after one or more attempts to repair the infolded device: five died of symptoms related to the infolding and five secondary to the intervention undertaken to correct the device infolding.
  
  
  CONCLUSIONS
  TAG device infolding appears to be an infrequent event, primarily occurring in young trauma patients secondary to excessive oversizing and severe proximal aortic angulation. However, there clearly exists a need for devices that treat such patients. As a result, future device designs should consider the compression failure mode when being designed in order to help prevent such events.
authors.affiliation: East Bay Cardiovascular Associates, 2485 High School Ave, Ste 312, Concord, CA 94520, USA. kasi@ebcvt.com
authors.forename: Karthikeshwar
authors.initials: K
authors.lastname: Kasirajan
authors.forename: Michael D
authors.initials: MD
authors.lastname: Dake
authors.forename: Alan
authors.initials: A
authors.lastname: Lumsden
authors.forename: Joseph
authors.initials: J
authors.lastname: Bavaria
authors.forename: Michel S
authors.initials: MS
authors.lastname: Makaroun
mesh_terms: D000328:Adult; D000368:Aged; D001013:Aorta, Thoracic / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D001027:Aortography / Q000379:methods; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation* / Q000401:mortality; D057510:Endovascular Procedures / Q000009:adverse effects / Q000295:instrumentation* / Q000401:mortality; D005260:Female; D006439:Hemodynamics; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000209:etiology* / Q000401:mortality / Q000503:physiopathology / Q000601:surgery; D011237:Predictive Value of Tests; D011474:Prosthesis Design; D011475:Prosthesis Failure; D012086:Reoperation; D018570:Risk Assessment; D012307:Risk Factors; D015607:Stents; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D055815:Young Adult