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

BACKGROUND: 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. METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.