Suprarenal versus infrarenal stent graft fixation on renal complications after endovascular aneurysm repair

Abstract

Objective: The effect of stent graft fixation type on renal function after endovascular aneurysm repair (EVAR) remains controversial. This systematic review and meta-analysis was conducted to determine whether suprarenal (SR) or infrarenal (IR) fixation influences the risk of renal complications after EVAR.

Methods: We searched MEDLINE and EMBASE with no date or language restrictions for comparative studies evaluating EVAR with SR vs IR fixation on renal dysfunction, renal artery stenosis, renal artery occlusion, renal infarction, and new need for hemodialysis. For each outcome, we calculated the absolute risk difference (RD) with a random effects meta-analysis and performed assessments of heterogeneity and publication bias. Post hoc subgroup analyses explored the influence of individual moderator variables.

Results: A total of 21 nonrandomized studies comparing SR vs IR fixation representing 4474 unique patients (SR, 1949; IR, 2525) were included. Baseline patient characteristics were similar between the SR and IR groups. Median patient follow-up was 12 months in each group. There were no statistically significant differences in the risk of any renal complication between SR and IR fixation groups. The absolute RD between the SR and IR fixation groups was <1%, with no evidence of heterogeneity or publication bias for renal dysfunction, renal artery stenosis, renal artery occlusion or new need for hemodialysis after EVAR. Renal infarction occurred in 6.4% of SR patients and in 2.5% of IR patients (P = .09), with evidence of heterogeneity (I(2) = 85%) and publication bias (Egger P = .08). Subgroup analyses revealed that older studies (median treatment period before 2000) reported greater risks of renal infarction with SR fixation (RD, 6.2%; P = .01). However, more contemporary studies (median treatment period after 2000) demonstrated no difference between SR and IR fixation on renal infarction risk (RD, 0.2%; P = .75).

Conclusions: There is no difference in the risk of postoperative renal complications when comparing stent grafts using SR vs IR fixation, particularly with newer-generation devices. Contemporary comparative studies with longer-term follow-up are warranted to further elucidate the influence of SR and IR fixation on renal complications.