Outcomes of Small Renal Artery Targets in Patients Treated by Fenestrated-Branched Endovascular Aortic Repair

Abstract

The aim was to evaluate renal related outcomes in patients who had incorporation of a small (<4.0mm) renal artery (RA) during fenestrated-branched endovascular aortic repair (F-BEVAR). A total of 215 consecutive patients enrolled in a prospective F-BEVAR trial were reviewed. Computed tomography angiography centreline of flow reconstruction was used to measure mean RA diameter. Patients who had at least one <4.0mm main or accessory RA incorporated by fenestration or directional branch (study group) were compared with patients who had incorporation of two≥5.0mm RAs (control group). Endpoints were technical success of RA incorporation, RA rupture and kidney loss, primary and secondary RA patency, RA branch instability and re-interventions, and renal function deterioration. Twenty-four patients with 28<4.0mm RAs (16 accessory and 12 main RAs) were compared with 144 patients with 288≥5.0mm incorporated RAs. Study group patients were significantly younger than controls (72±8 vs. 75±8 years, p=.04) and more often females (46% vs. 21%, p=.018); there were no differences in cardiovascular risk factors and aneurysm extent. Technical success was 92% for <4.0mm and 99% for ≥5.0mm RA incorporation (p=.05). Inadvertent RA rupture occurred in three patients in the study group (13%) and in one (1%) in the control group (p=.009) resulting in kidney loss in two study group patients (8%) and one (1%) control group patient (p=.05). At one year, primary patency was 79±9% vs. 94±1% (p<.001) and secondary patency was 84±8% vs. 97±1% (p<.001) for study vs. control group; freedom from branch instability was 79±9% vs. 93±2% (p=.005), respectively. There were no differences in re-intervention rates and renal function deterioration between the groups. The mean follow up time was 21±14 months. Incorporation of <4.0mm RAs during F-BEVAR is associated with lower technical success, higher risk of arterial disruption and kidney loss, and lower patency rates at one year.