Chimney performance in complex abdominal aortic aneurysms compared to fenestrated endovascular aortic repair

The chimney technique may offer an alternative approach for managing juxta- and pararenal abdominal aortic aneurysms (AAA). This analysis presents the outcomes of the chimney technique and compares elective chimney and fenestrated endovascular aortic repair (FEVAR) findings in complex AAA.

The STROBE statement was followed to conduct a single-center retrospective analysis of patients who underwent chimney for complex AAA from January 1, 2016, to December 31, 2024. A comparison between elective chimney and FEVAR cases was also performed. Primary outcomes included technical success, mortality and survival.

Seventy-two patients underwent chimney (94.4% males); 60 elective cases. Regarding the total chimney cohort, technical success was 98.6% and 30-day mortality 11.1%. Gutter endoleaks were detected in 6.9%; all resolved at 30 days. The mean follow-up was 36.8±5.8 months. Survival was 48.2% (standard error [SE] 9.5%) and freedom from reintervention was 87.3% (SE 6.5%) at 60 months. Forty-one elective FEVARs were compared to 60 elective chimney cases. Elective chimney patients had significantly larger aortic diameters (63 [Q1:56, Q3:78] mm vs. 56 [Q1:54, Q3:66] mm, P=0.02). Technical success (P=0.79) and 30-day mortality (P=0.30) were similar. The mean follow-up in elective chimney was longer compared to FEVAR (40.0±6.3 vs. 27.5±6.3 months; P=0.03). The estimated survival was consistently significantly lower in elective chimney cases (log rank; P=0.003) while freedom from reintervention was similar (P=0.88).

The chimney technique demonstrated acceptable 30-day outcomes. Compared to elective chimney, 30-day FEVAR outcomes were similar, but FEVAR survival was significantly higher. The need for reintervention was equal.