Post-endograft abdominal aortic aneurysm shrinkage varies among hospitals: observations from multicenter trials.
OBJECTIVE
To evaluate differences in abdominal aortic aneurysm (AAA) shrinkage among hospitals following protocol-driven patient selection and using endografts from a single manufacturer.


METHODS
Standardized inclusion criteria for the Talent endograft multicenter trials included AAA diameter >/=40 mm and proximal neck limits of length >/=5 mm, diameter 14 to 32 mm, and angle </=60 degrees. AAA reporting standards categories were used to classify distal aorta and common iliac artery involvement. Serial computed tomographic scans through 12-month follow-up were examined by independent core laboratory review. Significant shrinkage was defined as a >/=5-mm decrease in the AAA largest minor axis diameter. Trial sites with >10 complete study cases were selected for stepwise logistic regression analysis. In the 13 trial sites meeting this criterion, 323 patients (mean age 74; 93% men) were treated for aneurysms with a mean pretreatment diameter of 53 mm.


RESULTS
At 12 months, significant AAA shrinkage occurred in 192 (59%) cases. The AAA shrinkage rate was 71% to 82% at 3 sites, 60% to 64% at 4 sites, 45% to 50% at 4 sites, and 35% and 27% at the 2 remaining sites. In the multivariate analysis, the hospital site showed a strong, independent association with aneurysm shrinkage (p<0.04). Neck and pretreatment AAA diameters were also found to be important factors (p<0.04). Age, gender, AAA classification, neck length, and angle were not significant correlates. Sixty-four (20%) endoleaks (29 type I, 34 type II, and 1 type III) were observed. The incidence of proximal endoleak was significantly different among sites (p<0.001) and highest in the 3 sites with the lowest AAA shrinkage rate.


CONCLUSIONS
AAA shrinkage rates vary significantly among hospitals using the same endograft and protocol-defined patient selection criteria. Site-specific factors appear to be an important variable leading to successful endograft repair, as defined by post-endograft aneurysm shrinkage.
Kritpracha
Boonprasit
B
Jobst Vascular Center, Toledo, Ohio 43606, USA.
Beebe
Hugh G
HG
Criado
Frank J
FJ
Comerota
Anthony J
AJ
D000368:Aged; D000369:Aged, 80 and over; D017130:Angioplasty; D017544:Aortic Aneurysm, Abdominal / Q000000981:diagnostic imaging / Q000601:surgery*; D001807:Blood Vessel Prosthesis / Q000009:adverse effects; D002985:Clinical Protocols; D005260:Female; D005500:Follow-Up Studies; D005548:Foreign-Body Migration / Q000209:etiology; D006761:Hospitals; D006801:Humans; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D011475:Prosthesis Failure; D011859:Radiography; D012074:Remission Induction; D015607:Stents / Q000009:adverse effects; D016896:Treatment Outcome