Higher Risk for Morbidity and Non-Aortic Related Mortality in Type 2 Endoleak Patients Treated Outside of Instructions for Use

Objective To evaluate outcomes in patients with type 2 endoleak (T2E) and the impact of treatment outside the device instructions for use (IFU). Methods This retrospective single-center study included abdominal aortic aneurysms (AAA) patients who underwent EVAR (2011- 2024). Primary outcomes were 30-day and mid-term complications, reintervention, and mortality by T2E status. Propensity score matching was applied and secondary analysis stratified outcomes by IFU compliance, comparing within ( in IFU) or outside( out IFU) IFU in each T2E group. Results Among 154 EVAR patients (137 men (89.1%) and 17 women (11.0%); mean age 77.5 ± 7.6 years), 77 were T2E(−), and 77 were T2E(+). Baseline characteristics were similar. Thirty-day complications were comparable (T2E(−): 5, 6.4% vs T2E(+): 2, 2.56%, P = 0.72). The mean follow-up duration was 2.7 ± 2.4 years. Sac diameter change (Δ) decreased in the T2E(−) (7.7 ± 8.4 mm) and enlarged in the T2E(+) (1.79 ± 12.5 mm; P < 0.01). Mid-term graft-related complications (T2E(−): 3, 3.8% vs T2E(+): 49, 62.8%, P < 0.01) and reinterventions (T2E(−): 3, 3.8%, vs T2E(+): 20, 25.6% P < 0.01) were higher in the T2E(+) with no difference in mortality ( P = 1.00). These findings remained after excluding type 1 endoleaks. Among the T2E(+), those treated out IFU had longer hospital stays ( out IFU: 3.0 ± 2.8 days vs in IFU: 1.8 ± 2.0 days, P = 0.03), higher T1E ( out IFU: 3, 33.3% vs in IFU: 1, 4.34%, P < 0.01), higher rates of reintervention ( out IFU: 9, 100.0% vs in IFU:17; 24.6%, P < 0.01) and higher all-cause mortality than those within IFU criteria ( out IFU: 5, 55.0% vs in IFU: 13, 18.8%, P < 0.01). IFU status did not significantly affect outcomes in T2E(−) patients. Conclusions T2E is associated with sac growth and increased reinterventions, but not higher mortality. On subgroup analysis, those T2E(+) treated out IFU had longer hospitalizations, higher T1E rates, more reinterventions, and higher all-cause; but not aneurysmal-related mortality.