Ck. Zarins et al., Endoleak as a predictor of outcome after endovascular aneurysm repair: AneuRx multicenter clinical trial, J VASC SURG, 32(1), 2000, pp. 90-107
Citations number
39
Categorie Soggetti
Cardiovascular & Respiratory Systems","Cardiovascular & Hematology Research
Objective: The purpose of this study was to determine whether evidence of b
lood flow in the aneurysm sac (endoleak) is a meaningful predictor of clini
cal outcome after successful endovascular aneurysm repair.
Methods: We reviewed all patients in Phase II of the AneuRx Multicenter Cli
nical Trial with successful stent graft implantation and predischarge contr
ast computed tomographic (CT) imaging. The clinical outcome of patients wit
h evidence of endoleak was compared with the outcome of patients without ev
idence of endoleak. The CT endoleak status before hospital discharge at 6,
12, and 24 months was determined by each clinical center as well as by an i
ndependent core laboratory. Endoleak status at 1 month was assessed with du
plex scanning examination or CT at each center without confirmation by the
core laboratory.
Results: Centers reported endoleaks in 152 (38%) of 398 patients on predisc
harge CT, whereas the core laboratory reported endoleaks in 50% of these pa
tients (P < .001). The center-reported endoleak rate decreased to 13% at 1
month. Follow-up extended to 2 years (mean, 10 +/- 4 months). One patient h
ad aneurysm rupture and underwent successful open repair at 14 months. This
patient had a Type I endoleak at discharge but no endoleak at 1 month or a
t subsequent follow-up times. There were no differences between patients wi
th and patients without endoleak at discharge in the following outcome meas
ures: patient survival, aneurysm rupture, surgical conversion, the need for
an additional procedure for endoleak or graft patency, aneurysm enlargemen
t more than 5 mm, the appearance of a new endoleak, or stent graft migratio
n. Despite a higher endoleak rate identified by the core laboratory neither
the endoleak rate reported by the core laboratory nor the endoleak rate re
ported by the center at discharge was significantly related to subsequent o
utcome measures. Patients with endoleak at 1 month were more likely to unde
rgo an additional procedure for endoleak than patients without endoleaks. P
atients with Type I endoleaks at discharge and patients with endoleak at 1
month were more likely to experience aneurysm enlargement at 1 year. Howeve
r, there was no difference in patient survival, aneurysm rupture rate, or p
rimary or secondary success rate between patients with or without endoleak.
Actuarial survival of all patients undergoing endovascular aneurysm repair
was 96% at 1 year and was independent of endoleak status. Primary outcome
success was 92% at 12 months and 88% at 18 months. Secondary outcome succes
s was 96% at 12 months and 94% at 18 months.
Conclusions: The presence or absence of endoleak on CT scan before hospital
discharge does not appear to predict patient survival or aneurysm rupture
rate after endovascular aneurysm repair using the AneuRx stent graft. Altho
ugh the identification of blood flow in the aneurysm sac after endovascular
repair is a meaningful finding and may at times indicate inadequate stent
graft fixation, the usefulness of endoleak as a primary indicator of proced
ural success or failure is unclear. Therefore, all patients who have underg
one endovascular aneurysm repair should be carefully followed up regardless
of endoleak status.