title: Geometric Alteration of Renal Arteries After Fenestrated Grafting and the Impact on Renal Function.
abstract: BACKGROUND
  This study aims to investigate the degree of geometric change on renal arteries and its impact on renal function after fenestrated endovascular aortic repair (fEVAR).
  
  
  METHODS
  Twenty-five patients with fEVAR were included. There were 47 renal arteries target vessels, and 43 of these (22 left and 21 right vessels) stented successfully. Their preoperative and first postoperative follow-up computed tomography (CT) images were reconstructed using the Aquarius workstation (TeraRecon, San Mateo, CA, USA). The superior mesenteric artery (SMA) or celiac axis (if SMA was stented) was appointed as reference origin. The longitudinal orientation of a renal artery or a stent was represented by a takeoff angle (ToA) between the renal artery or stent and the distal abdominal aorta. The postoperative stent ToAs were compared with those of preoperative renal arteries. Preoperative and short-term postoperative serum creatinine levels were measured. Renal function impairment was indicated as a >30% or >2.0 mg/dL rise in serum creatinine compared to the preoperative level. The relationship between postoperative renal function impairment and the stent orientation or geometric changes in renal arteries was correlated.
  
  
  RESULTS
  The patency rate of renal arteries was 100% at the first postoperative CT review. The average ToAs of both renal arteries were significantly enlarged after stenting (P < 0.05). Seven stent deformations (16.3%) in four patients (16.0%) were observed. They were attributed to caudal misalignment of the fenestrated stent graft (n = 6) or inaccurate graft sizing (n = 1). There was no stent fracture or target vessel loss. Postoperatively, nine patients (36.0%) at day 1 and 10 patients (41.7%) after 3 months suffered the renal function impairment. This was found not to be associated with the stent angulation or angular change of the renal arteries (both P > 0.05). The three patients with stent deformation due to misalignment suffered postoperative renal function impairment and continuing deterioration in renal function.
  
  
  CONCLUSIONS
  Implanted renal stents could angulate renal arteries more cephalad after fenestrated stenting. Postoperative renal function impairment was not associated with the stent orientation and changes in vessel orientation. Accurate fenestrated alignment is important to maintain stent performance and preserve renal function.
authors.affiliation: Division of Vascular Surgery, Department of Surgery, Queen Mary Hospital, The University of Hong Kong, Hong Kong, China.
authors.forename: Jiale
authors.initials: J
authors.lastname: Ou
authors.affiliation: Division of Vascular Surgery, Department of Surgery, Queen Mary Hospital, The University of Hong Kong, Hong Kong, China.
authors.forename: Yiu-Che
authors.initials: YC
authors.lastname: Chan
authors.affiliation: Division of Vascular Surgery, Department of Surgery, Queen Mary Hospital, The University of Hong Kong, Hong Kong, China.
authors.forename: Crystal Yin-Tung
authors.initials: CY
authors.lastname: Chan
authors.affiliation: Division of Vascular Surgery, Department of Surgery, Queen Mary Hospital, The University of Hong Kong, Hong Kong, China. Electronic address: wkcheng@hku.hk.
authors.forename: Stephen W K
authors.initials: SWK
authors.lastname: Cheng
mesh_terms: D000368:Aged; D001011:Aorta / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D001027:Aortography / Q000379:methods; D015415:Biomarkers / Q000097:blood; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D000072226:Computed Tomography Angiography; D003404:Creatinine / Q000097:blood; D016208:Databases, Factual; D057510:Endovascular Procedures / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D005260:Female; D006801:Humans; D007668:Kidney / Q000098:blood supply* / Q000503:physiopathology*; D007674:Kidney Diseases / Q000209:etiology / Q000503:physiopathology; D008297:Male; D011474:Prosthesis Design; D011475:Prosthesis Failure; D012077:Renal Artery / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D012079:Renal Circulation; D012307:Risk Factors; D015607:Stents; D013997:Time Factors; D016896:Treatment Outcome; D014654:Vascular Patency
chemical_list: D015415:Biomarkers; D003404:Creatinine