Renal artery involvement (RAI) in endovascular aneurysm repair (EVAR) is “highly predictive of the need for postoperative and permanent dialysis,” Anastasia Plotkin (University of Southern California, Los Angeles, USA) and colleagues write in the Journal of Vascular Surgery (JVS). They also report that RAI without revascularisation is associated with lower overall survival.
Plotkin et al detail that revascularisation after intentional or unintentional renal artery coverage “is not always technically successful,” adding that loss of a single renal artery in this patient population may result in the need for postoperative dialysis. In the present study, the investigators aimed to compare outcomes after EVAR stratified by RAI.
The researchers analysed data from the EVAR and thoracic endovascular aortic repair (TEVAR)/complex EVAR modules in the Vascular Quality Initiative (VQI) registry from 2009–2018. The primary outcome was postoperative dialysis, and secondary outcomes were 30-day mortality, dialysis at follow-up, postoperative renal function, and two-year survival.
Plotkin and colleagues detail that repair type cohorts were defined as: 1) no RAI (NRAI); 2) renal artery involvement with revascularisation (RAI-R); and 3) RAI and no revascularisation (RAI-NR). They relay that 25,724 out of 54,020 patients in the EVAR and TEVAR/complex EVAR modules in the VQI met the criteria for inclusion—24,879 NRAI, 733 RAI-R, and 112 RAI-NR.
The investigators report that postoperative dialysis was higher in RAI-NR (0.7% NRAI vs. 2.2% RAI-R vs. 17% RAI-NR, p<0.0001), as were 30-day mortality and dialysis at follow-up. On multivariate analysis, they add, RAI-R (odds ratio [OR], 2.2; p=0.03) and RAI-NR (OR, 5.9; p<0.0001) were independent predictors of postoperative dialysis and remained so after excluding ruptures: RAI-R (OR, 3; p=0.003) and RAI-NR (OR, 22.3; p<0.0001).
Finally, Plotkin et al communicate that other independent predictors of postoperative dialysis were worse preoperative renal function, symptomatic presentation, any preoperative/intraoperative blood transfusion, and larger blood loss (≥200ml).
“These risks should be taken into consideration with planning and performing EVAR and should be weighed against the risks of open repair when considering treatment options,” the authors conclude.