title: Medtronic Freestyle aortic bioprosthesis: a potential option for haemodialysis patients†.
abstract: OBJECTIVE
  End-stage renal disease patients on regular haemodialysis are at higher risk of calcification. Therefore, many surgeons have concerns regarding the implantation of bioprostheses in such patients. The haemodynamic advantages of stentless aortic bioprostheses support their use; however, these have not been studied yet in end-stage renal disease patients. We studied accordingly the early and mid-term outcomes of aortic valve replacement (AVR) using Medtronic Freestyle stentless aortic bioprostheses in this subset of patients in comparison with stented aortic bioprostheses.
  
  
  METHODS
  We retrospectively studied two groups of consecutive patients on regular haemodialysis who required AVR between 2007 and 2013. Non-Freestyle (NFS) group received stented aortic bioprostheses (36 patients) and Freestyle (FS) group received Medtronic Freestyle aortic bioprostheses (48 patients). Follow-up ranged from 2 to 76 months with a mean follow-up of 36.3 ± 25 months.
  
  
  RESULTS
  Patients in both groups showed similar demographic characters regarding age (76.4 ± 8.1 vs 74.9 ± 7.2 years; P = 0.35), male gender (58 vs 60%; P = 0.57) and diabetes mellitus (42 vs 48%; P = 0.57). Smaller aortic bioprostheses were implanted in the NFS (23.3 ± 1.2 vs 25.4 ± 2.1; P < 0.001) with consequently higher postoperative mean gradients (14.1 ± 4.1 vs 11.9 ± 5.3 mmHg; P = 0.004). No significant differences were noted regarding postoperative neurological disorder (8 vs 12%; P = 0.73), deep sternal wound infection (3 vs 4%; P = 0.68), re-exploration (8 vs 8%; P = 0.91) and in-hospital mortality (6 vs 4%; P = 0.92). Mid-term follow-up showed higher prosthetic valve calcification and/or sclerosis in NFS group (25 vs 6%; P = 0.015), whereas no significant differences were noticed between the two groups regarding stroke (0 vs 8%; P = 0.13), endocarditis (0 vs 4%; P = 0.50), 36- and 72-month survival (51 ± 2%, 14 ± 4% vs 55 ± 2%, 19 ± 3%, respectively; P = 0.45).
  
  
  CONCLUSIONS
  Aortic bioprostheses are a good option for haemodialysis patients requiring AVR, offering acceptable mid-term survival. The Medtronic Freestyle aortic bioprostheses could allow the implantation of larger bioprostheses inferring consequently lower mean gradients, with a potentially higher resistance to calcification and sclerosis in haemodialysis patients.
authors.affiliation: Department of Cardiac Surgery, Heart Institute Lahr, Lahr, Germany Department of Cardio-Thoracic Surgery, Faculty of Medicine, Alexandria University, Alexandria, Egypt yasserhegazy@yahoo.com.
authors.forename: Yasser Y
authors.initials: YY
authors.lastname: Hegazy
authors.affiliation: Department of Cardiac Surgery, Heart Institute Lahr, Lahr, Germany Department of Cardio-Thoracic Surgery, Faculty of Medicine, Alexandria University, Alexandria, Egypt.
authors.forename: Amr
authors.initials: A
authors.lastname: Rayan
authors.affiliation: Department of Cardiac Surgery, Heart Institute Lahr, Lahr, Germany.
authors.forename: Ralf
authors.initials: R
authors.lastname: Sodian
authors.affiliation: Department of Cardio-Thoracic Surgery, Faculty of Medicine, Alexandria University, Alexandria, Egypt.
authors.forename: Wael
authors.initials: W
authors.lastname: Hassanein
authors.affiliation: Department of Cardiac Surgery, Heart Institute Lahr, Lahr, Germany School of Medicine, Faculty of Health, University of Witten Herdecke, Witten, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Ennker
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000503:physiopathology / Q000601:surgery*; D001022:Aortic Valve Insufficiency / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D001024:Aortic Valve Stenosis / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D001705:Bioprosthesis; D004696:Endocarditis / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications / Q000175:diagnosis / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D011474:Prosthesis Design; D006435:Renal Dialysis / Q000009:adverse effects; D012189:Retrospective Studies; D012307:Risk Factors; D015607:Stents; D013997:Time Factors; D016896:Treatment Outcome
keywords: Aortic bioprosthesis; Calcification; Freestyle; Haemodialysis