Cook's Zenith Fenestrated EVAR Graft Compares Favorably to Open Repair for Complex AAA in Multicenter Registry
February 27, 2019—In Journal of Vascular Surgery (JVS), Rens R.B. Varkevisser, BS, et al published findings from a comparison of perioperative outcomes after elective repair of complex abdominal aortic aneurysms (AAAs) using the Zenith fenestrated endovascular graft (ZFEN; Cook Medical), open repair of complex AAAs, and infrarenal endovascular aneurysm repair (EVAR) in a nationwide multicenter registry.
In JVS, the investigators concluded that ZFEN EVAR is associated with lower perioperative morbidity and mortality compared with open complex AAA repair, and outcomes are comparable to those of infrarenal EVAR. Long-term durability of ZFEN compared with open complex AAA repair warrants future research, advised the investigators in JVS.
As the investigators explained in JVS, the background of the study is that, although ZFEN has expanded the anatomic eligibility of EVAR for patients complex AAAs, current data on ZFEN mainly consist of single-institution experiences and show conflicting results. Therefore, they conducted this multicenter registry.
For the study, all patients undergoing elective AAA repair using ZFEN, open complex AAA repair, and standard infrarenal EVAR between 2012 and 2016 were identified within the American College of Surgeons National Surgical Quality Improvement Program targeted vascular module. Open complex AAA repairs were defined as those with a juxtarenal or suprarenal proximal AAA extent in combination with an aortic cross-clamping position above at least one renal artery.
The primary outcome was perioperative mortality, which was defined as death within 30 days or within the index hospitalization. Secondary outcomes included postoperative renal dysfunction (creatinine concentration increase of > 2 mg/dL from preoperative value or new dialysis), occurrence of any complication, procedure times, blood transfusion rates, and length of stay. The investigators identified 6,825 AAA repairs: 220 ZFENs, 181 open complex AAA repairs, and 6,424 infrarenal EVARs.
As summarized in JVS, the investigators reported that when compared by univariate analysis with open complex AAA repair, ZFEN demonstrated lower rates of:
- Perioperative mortality (1.8% vs 8.8%; P = .001)
- Postoperative renal dysfunction (1.4% vs 7.7%; P = .002)
- Overall complications (11% vs 33%; P < .001)
In addition, fewer patients undergoing ZFEN received blood transfusions (22% vs 73%; P < .001), and median length of stay was shorter (2 vs 7 days; P < .001).
After adjustment, open complex AAA repair compared with ZFEN was associated with higher odds of the following:
- Perioperative mortality (odds ratio [OR], 4.9; 95% confidence interval [CI], 1.4–18)
- Postoperative renal dysfunction (OR, 13; 95% CI, 3.6–49)
- Overall complication rates (OR, 4.2; 95% CI, 2.3–7.5)
ZFEN versus infrarenal EVAR presented comparable rates of the following:
- Perioperative mortality (1.8% vs 0.8%; P = .084)
- Renal dysfunction (1.4% vs 0.7%; P = .19)
- Any complication (11% vs 7.7%; P = .09)
After adjustment, there was no significant difference between the odds of perioperative mortality, postoperative renal dysfunction, or any complication between infrarenal EVAR and ZFEN, reported the investigators in JVS.