Trial Results
Endovascular vs Open Aortic Repair in the UK
EVAAR-UK
Published 1 May 2026
Primary Outcome
At 5 years, all-cause mortality was 11.7% in the EVAR group compared with 12.4% in the open repair group (absolute difference −0.7%, 95% CI −5.2 to 3.8). There was no statistically significant difference in all-cause mortality between endovascular and open repair of infrarenal abdominal aortic aneurysms at 5 years.
Statistical Summary
Primary endpoint (all-cause mortality at 5 years): HR 0.94 (95% CI 0.62–1.43), p = 0.77. 30-day operative mortality: EVAR 1.4% vs open 3.9%, p = 0.08. Kaplan-Meier survival curves converged between 2 and 3 years post-randomisation.
Secondary Outcomes
30-day operative mortality was lower with EVAR (1.4% vs 3.9%) though this did not reach statistical significance (p = 0.08). Re-intervention rates were significantly higher in the EVAR group (22.1% vs 9.8%, p < 0.001). Aneurysm-related mortality was similar between groups (3.2% EVAR vs 3.8% open, p = 0.72). Quality of life (EQ-5D-5L) favoured EVAR at 1 month (mean difference 0.12, p < 0.001) but was equivalent from 6 months onwards. Mean length of index hospital stay was 4.2 days for EVAR vs 8.7 days for open repair (p < 0.001). EVAR was associated with an incremental cost-effectiveness ratio of £18,400 per QALY gained at 5 years.
Safety & Adverse Events
Serious adverse events occurred in 34.2% of EVAR patients and 38.6% of open repair patients. In the EVAR group, the most common complications were endoleak (type II in 18.3%, type I or III in 4.2%), graft migration (2.1%), and limb occlusion (3.5%). In the open group, common complications included wound infection (8.4%), incisional hernia (6.3%), and cardiac events (5.6%). There were 2 cases of aortic graft infection in the open group (1.4%) and none in the EVAR group. No aneurysm ruptures occurred in either group during follow-up.
Clinical Conclusion
Modern EVAR and open repair of infrarenal AAA produce equivalent long-term survival at 5 years. EVAR offers advantages in early recovery and short-term quality of life but carries a significantly higher re-intervention burden. The choice between EVAR and open repair should be individualised based on patient anatomy, fitness, and informed preference.
Discussion
The EVAAR-UK trial provides contemporary evidence that third-generation stent-grafts have not altered the fundamental survival equivalence between EVAR and open repair observed in earlier landmark trials (EVAR-1, DREAM, OVER). The convergence of survival curves between 2 and 3 years is consistent with historical data, suggesting a persistent late hazard in EVAR patients, though the mechanism remains debated. The re-intervention rate of 22.1% in the EVAR arm, while concerning, is lower than the 29% reported in EVAR-1 at 4 years, suggesting iterative device improvement. However, most re-interventions were for type II endoleaks, whose clinical significance remains uncertain. The cost-effectiveness analysis suggests EVAR falls within conventional willingness-to-pay thresholds for the NHS when the quality of life benefit in the first 6 months is accounted for. Limitations include the relatively short follow-up period for a disease with implications beyond 10 years, and the exclusion of emergency presentations which represent a substantial proportion of AAA workload. Extended follow-up to 10 years is planned and will be critical for definitive guidance.
Publication
Endovascular versus Open Aortic Repair in Patients Fit for Both Procedures: Five-Year Results of the EVAAR-UK Randomised Controlled Trial
European Journal of Vascular and Endovascular Surgery — May 2026
Video Summary
EVAAR-UK 5-Year Results — Presentation at the Vascular Society Annual Meeting 2026
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