Early Outcomes for Fenestrated and Chimney Endografts in the Treatment of Pararenal Aortic Pathologies Are Not Significantly Different: A Systematic Review With Pooled Data Analysis

Purpose To compare short-term outcomes between fenestrated and chimney endografts for pararenal aortic pathologies.Methods An English-language literature search up to January 2012 found 129 articles evaluating the immediate outcomes of endovascular repair of degenerative juxta-/suprarenal aortic aneurysms, type I endoleaks, and para-anastomotic aneurysms using the chimney technique or fenestrated endografts. Data concerning thoracoabdominal aortic aneurysms, ruptured aneurysms, and reports with <5 cases were excluded (n=84). An additional 28 articles were excluded for insufficient data, leaving 17 articles for review: 5 dealing with chimney grafts in 123 patients with pararenal aortic pathologies and 12 presenting data on 631 patients undergoing fenestrated stent-grafting. The composite endpoints were 30-day mortality, deterioration of renal function, new postoperative dialysis dependence, and endoleak rate.Results Cumulative 30-day procedure-related mortality was 0.58% (95% CI 0.0% to 2.93%) for the chimney group (n=3) and 1.17% (95% CI 0.26% to 2.09%, p=0.645) for the f-EVAR group (n=9). In the f-EVAR group, 86 (9.67%;95% CI 4.77% to 14.57%) patients suffered from postoperative renal impairment vs. 16 (12.43%) patients in the chimney group (95% CI 2.39% to 22.48%, p=0.628). In the chimney group, 4 (0.57%;95% CI 0.0% to 2.94%) patients required persistent postoperative dialysis in contrast to the 1.33% (95% CI 0.29% to 2.37%, p=0.567) rate (n=9) in patients undergoing f-EVAR. There were also no significant differences recorded in the endoleak rate: 1.93% (95% CI 0.0% to 4.82%) of the chimney patients had a persistent type Ia endoleak vs. 2.06% (95% CI 0.69% to 3.43%) for the f-EVAR group (p=0.939). For type II endoleaks, the rates were 2.16% (95% CI 0.0% to 10.77%) for the chimney group vs. 6.88% (95% CI 1.92% to 11.83%) for the f-EVAR group (p=0.352). No patient in the chimney group had a type III endoleak, and the rate was low in the f-EVAR group (0.32%,95% CI 0.0% to 0.91%, p=0.079).Conclusion No statistically significant differences were found between the two endovascular approaches for pararenal aortic pathologies in terms of 30-day mortality, renal impairment, or endoleak. These findings support the assumption that chimney grafts may be a reliable alternative in the treatment of pararenal aortic pathologies.