RS17 - Differences in Renal Artery Outcomes Between Fenestrations Versus Directional Branches In Patients Treated for Complex Abdominal and Extent IV Thoracoabdominal Aortic Aneurysms

Friday, June 12, 2026

9:01 AM - 9:08 AM ET

Location: Hynes CC, Third Level, Ballroom B

Presenting Author only(s)

Jesus Porras, MD

Aortic Clinical Research Fellow
Utsouthwestern
Dallas, Texas

Co-Author(s)

YH

Ying Huang

Associate Professor of Surgery
Baylor College of Medicine
Andres Schanzer, MD (he/him/his)

Professor
Division of Vascular and Endovascular Surgery, University of Massachusetts Chan Medical School, Worcester, MA
Worcester, Massachusetts
Darren B. Schneider, MD

Chief of the Division of Vascular Surgery and Endovascular Therapy
University of Pennsylvania Perelman School of Medicine
Philadelphia, Pennsylvania
Adam W. Beck, MD

Professor of Surgery
University of Alabama at Birmingham
Birmingham, Alabama
Matthew J. Eagleton, MD (he/him/his)

Chief, Vascular and Endovascular Surgery
Massachusetts General Hospital
Boston, Massachusetts
Mark A. Farber, MD

Professor
University of North Carolina
Chapel Hill, North Carolina
WL

W. Anthony Lee, MD (he/him/his)

Chief, Vascular Surgery
Baptist Health South Florida
Boca Raton, Florida
Sara L. Zettervall, MD

Associate Professor of Surgery
Division of Vascular Surgery, Department of Surgery, University of Washington, Seattle, WA
University of Washington, Seattle WA, Washington
Matthew P. Sweet

Professor of Surgery
University of Washington
Seattle, Washington
WG

Warren J. Gasper, MD

Chief, Vascular Surgery Section
San Francisco VA Health Care System
San Francisco, California
MB

Mirza S. Baig

Associate Professor, Division of Vascular and Endovascular Surgery
University of Texas Southwestern Medical Center
Dallas, Texas
GO

Gustavo Oderich

Professor of surgery
Michael E. DeBakey Department of Surgery, Division of Vascular and Endovascular Surgery, Baylor College of Medicine, Houston, TX

Senior Author Discussant(s)

Carlos H. Timaran, MD, MS

Professor of Surgery
University of Texas Southwestern Medical Center Dallas
Dallas, Texas

Objectives: Off-the-shelf multibranched stent-grafts have been increasingly utilized to treat complex abdominal (CAAAs) and extent IV thoracoabdominal aortic aneurysms (TAAAs). Although fenestrations and directional branches (DBs) are both used during fenestrated-branched endovascular aortic repair (FB-EVAR), DBs have been associated with increased risk of renal artery occlusion. The purpose of this study is to analyze renal artery outcomes of fenestrations versus DBs in patients with CAAAs and Extent IV TAAAs.

Methods: The clinical data of 3,693 consecutive patients enrolled in ten prospective, nonrandomized, sponsor-investigator investigational device exemption studies (2005-2025) were reviewed. We included in the analysis 2,044 patients (75% men, mean age 75+/-7 years-old) treated by FB-EVAR for CAAAs and Extent IV TAAAs, defined by aneurysm extension up to the level of the celiac axis. The primary endpoint was freedom from renal target-vessel instability (TVI), defined as a composite of target-vessel occlusion, type Ic/IIIc endoleak, kinking or stenosis >50%, or any target-vessel–related reintervention, death or rupture. Secondary endpoints included individual components of TVI and primary patency. Kaplan-Meier analysis and multivariable Cox regression models were performed.

Results: Among 7,645 targeted vessels incorporated by 5,656 (74%) fenestrations and 1,989 (26%) DBs, 3858 renal arteries were incorporated using 2,938 (76%) fenestrations and 920 (24%) DBs. Fenestrations were more frequently selected for CAAAs (68%) and for renal arteries (63%), whereas DBs were predominantly used for Extent IV TAAAs (77%) and mesenteric arteries (85%). Five-year estimate of freedom from renal TVI was 83% (95 confidence interval [CI], 82-84%) for fenestrations and 74% (95% CI, 72-76%) for DBs (Figure 1); DBs had a 1.69-fold increased unadjusted risk of TVI (95% CI, 1.39-2.05; P<.001). At 5-years, renal fenestrations were associated with lower rates of occlusion (7% vs. 18% [95% CI, 6-7 % vs. 16-20%]; P<.001) and type Ic endoleak (2% vs. 4% [95% CI, 2-3% vs. 3-5%]; P=.010). Primary renal artery patency was higher for fenestrations (92% vs 82% [95% CI, 91-92% vs. 80-84%]; P<.001). In the multivariable analysis, DBs, number of anticoagulants, and aneurysm size were independently associated with increased risk of renal TVI, whereas older age was protective (each P<.05).

Conclusions: Among patients treated for CAAAs and Extent IV TAAAs, the risk of renal TVI is lower for fenestrations compared to DBs. Despite FDA-approval of only branch-based designs, these findings suggest that fenestrations should remain the preferred renal incorporation strategy for aneurysms confined to the abdominal aorta whenever feasible.