Increased Aortic Sac Regression and Decreased Infrarenal Aortic Neck Dilation After Fenestrated Endovascular Aneurysm Repair Compared With Standard Endovascular Aneurysm Repair

Abstract

Aortic neck dilation (AND) can occur in nearly 25% of patients after EVAR, resulting in loss of proximal seal and aortic rupture. Fenestrated endovascular aneurysm repair (FEVAR) affords increased treatment options for patients with shorter infrarenal aortic necks; however, AND has not been well characterized in these patients. This study sought to compare AND in patients undergoing FEVAR vs standard endovascular aneurysm repair (EVAR). Retrospective review was conducted of prospectively collected data of 20 consecutive FEVAR patients (Cook Zenith fenestrated; Cook Medical, Bloomington, Ind) and 20 EVAR patients (Cook Zenith). Demographic and anatomic characteristics, procedural details, and clinical outcome were analyzed. Preoperative, 1-month postoperative, and longest follow-up computed tomography scans were analyzed using a dedicated three-dimensional workstation. Abdominal aortic aneurysm (AAA) neck diameter was measured in 5-mm increments from the lowest renal artery. Standard statistical analysis was performed. Demographic characteristics did not differ significantly between the two cohorts. The FEVAR group had larger mean aortic diameter at the lowest renal artery, shorter infrarenal aortic neck length, increased prevalence of nonparallel neck shape, and longer AAA length (Table). On follow-up imaging, the suprarenal aortic segment dilated significantly more at all suprarenal locations in the FEVAR cohort, whereas the infrarenal aortic neck segment dilated significantly less compared with the EVAR group (Table). The FEVAR group demonstrated significantly greater sac regression vs the EVAR group. Positive aortic remodeling, as evidenced by increased distance from the celiac axis to the most cephalad margin of the AAA, occurred to a more significant degree in the FEVAR cohort. Device migration, endoleak occurrence, and need for reintervention were similar in both groups. Compared with EVAR, patients undergoing FEVAR had greater extent of suprarenal AND, consistent with a more diseased native proximal aorta. However, the infrarenal neck, which is shorter and also more diseased in FEVAR patients, appears more stable in the postoperative period compared with EVAR cases. Moreover, the FEVAR cohort had significantly greater sac shrinkage and improved aortic remodeling. The suprarenal seal zone in FEVAR may confer a previously undescribed increased level of protection against infrarenal neck dilation and lessen endotension, resulting in more rapid and dramatic sac shrinkage and contributing to a more durable aortic repair.TableDemographics, radiographic data, and outcomes of fenestrated endovascular aneurysm repair (FEVAR) vs endovascular aneurysm repair (EVAR)FEVAREVARP valueDemographics No. of patients20201 Longest CT follow-up, months29.3 ± 16.129.8 ± 16.1.922 Age at procedure, years75.4 ± 9.6775.35 ± 7.07.985 Male85100.231 CAD55501 COPD2510.407 DM1025.407 HTN80801 Active smoker2510.407 Preoperative creatinine level, mg/dL1.06 ± 0.191.07 ± 0.22.88Baseline radiographic data Diameter at lowest renal, mm29.2 ± 7.1924.6 ± 2.94.012 Mean device diameter, mm30.1 ± 3.728.1 ± 3.8.098 Mean device oversizing11.614.3.354 Infrarenal neck length, mm6.65 ± 5.0435.32 ± 14.77<.0001 Nonparallel neck shape8550.041 Severe neck thrombus2010.661 Severe neck calcification551 Length of proximal sealing, mm33.37 ± 9.4531.21 ± 9.19.496 AAA maximum diameter, mm60.44 ± 10.2358.95 ± 11.09.662 AAA length, mm97.12 ± 27.5173.96 ± 18.43.003Diameter changes CA42.22 SMA93.5.0098 +20 mm9.92.7.0008 +15 mm9.92.3.001 +10 mm12.46.2.002 +5 mm13.15.9.002 Lowest renal10.45.9.26 −5 mm9.911.1.77 −10 mm6.712.9.13 −15 mm1.714.3.0009 −20 mm2.116.6.03 AAA maximum diameter−15.7−4.9.04Distance changesCA to aneurysm29.93.4.0167CA to TOG11.713.4.85Outcomes Type IA endoleak on follow-up00N/A Type II endoleak on follow-up3545.748 Branch vessel occlusion00N/A Device-related reintervention1051 All-cause mortality10151 Aorta-related mortality00N/AAAA, Abdominal aortic aneurysm; CA, celiac artery; CAD, coronary artery disease; COPD, chronic obstructive pulmonary disease; CT, computed tomography; DM, diabetes mellitus; HTN, hypertension; N/A, not applicable; SMA, superior mesenteric artery; TOG, top of graft.Categorical variables are presented as percentage. Continuous variables are presented as mean ± standard deviation. Open table in a new tab