title: Five-year outcomes of the PYTHAGORAS U.S. clinical trial of the Aorfix endograft for endovascular aneurysm repair in patients with highly angulated aortic necks.
abstract: Early and midterm outcomes of the Prospective Aneurysm Trial: High Angle Aorfix Bifurcated Stent Graft (PYTHAGORAS) trial in patients with highly angulated aortic necks (≥60 degrees) have already been published and shown comparable outcomes to other endografts in normal anatomy. Herein, we present the long-term outcomes of the PYTHAGORAS trial of Aorfix (Lombard Medical, Irvine, Calif) for patients with highly angulated aortic neck anatomy.
  
  
  
  The Aorfix endograft is a highly conformable nitinol/polyester device designed for transrenal fixation. The U.S. trial enrolled 218 patients and observed all patients at 1 month, 6 months, and 12 months and then annually for a total of 5 years. Endovascular aneurysm repair (EVAR)-specific complications were compared between the standard-angle (<60 degrees) and highly angulated (≥60 degrees) neck groups at 5 years using standard statistical methods. Kaplan-Meier analysis was performed to evaluate the overall 5-year survival and freedom from aneurysm rupture, aneurysm-related mortality, and reintervention.
  
  
  
  Of the 218 patients enrolled in the trial, there were 67 patients in the standard-angle neck group (I) and 151 patients in the highly angulated neck group (II). Mean proximal neck angle was 45 degrees in group I vs 83 degrees in group II (P < .001). At 5 years, 87% of surviving patients were followed up. The 5-year EVAR-specific results showed no type I or type III endoleak in either group, 4% migration in group I vs 3% in group II, and 4% sac expansion in group I vs 15.0% in group II (P ≥ .27). The 5-year freedom from all-cause mortality was 69% (73% in group I vs 68% in group II; P = .43); from aneurysm-related mortality, 96% (99% vs 95%; P = .44); from aneurysm rupture, 99% (99% vs 99%; P = 1.0); and from device-related secondary intervention, 83% (88% vs 80%; P = .18). None of these differed between groups.
  
  
  
  The U.S. PYTHAGORAS trial of the Aorfix endograft is the first EVAR clinical trial to include a majority of highly angulated (≥60 degrees) infrarenal aortic necks and is the first to produce evidence after 5 years of implantation. Despite predictors of worse short- and long-term outcomes, pertinent outcomes were better than or similar to those of trials with less severe anatomy. These results support the use of this "on-label" endovascular option, particularly in patients with highly angulated aortic neck anatomy.
authors.affiliation: Division of Vascular Surgery and Endovascular Therapy, Johns Hopkins University School of Medicine, Baltimore, Md. Electronic address: bmalas1@jhmi.edu.
authors.forename: Mahmoud B
authors.initials: MB
authors.lastname: Malas
authors.affiliation: Division of Vascular Surgery and Endovascular Therapy, Johns Hopkins University School of Medicine, Baltimore, Md.
authors.forename: Caitlin W
authors.initials: CW
authors.lastname: Hicks
authors.affiliation: Division of Vascular Surgery and Endovascular Therapy, Emory University School of Medicine, Atlanta, Ga.
authors.forename: William D
authors.initials: WD
authors.lastname: Jordan
authors.affiliation: Department of Vascular Surgery, Southern Illinois University School of Medicine, Springfield, Ill.
authors.forename: Kim J
authors.initials: KJ
authors.lastname: Hodgson
authors.affiliation: Division of Vascular Surgery and Endovascular Therapy, Baylor College of Medicine, Houston, Tex.
authors.forename: Joseph L
authors.initials: JL
authors.lastname: Mills
authors.affiliation: Division of Vascular Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pa.
authors.forename: Michel S
authors.initials: MS
authors.lastname: Makaroun
authors.affiliation: Division of Vascular and Endovascular Surgery, Brigham and Women's Hospital, Boston, Mass.
authors.forename: Michael
authors.initials: M
authors.lastname: Belkin
authors.affiliation: Section of Vascular Surgery, Dartmouth-Hitchcock Medical Center, Lebanon, NH.
authors.forename: Mark F
authors.initials: MF
authors.lastname: Fillinger
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001012:Aorta, Abdominal / Q000000981:diagnostic imaging / Q000601:surgery*; D017544:Aortic Aneurysm, Abdominal / Q000000981:diagnostic imaging / Q000401:mortality / Q000601:surgery*; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation* / Q000401:mortality; D018572:Disease-Free Survival; D057510:Endovascular Procedures / Q000009:adverse effects / Q000295:instrumentation* / Q000401:mortality; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D011183:Postoperative Complications / Q000209:etiology / Q000401:mortality / Q000628:therapy; D011446:Prospective Studies; D011474:Prosthesis Design; D019233:Retreatment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States