title: Randomized comparison of exercise haemodynamics of Freestyle, Magna Ease and Trifecta bioprostheses after aortic valve replacement for severe aortic stenosis.
abstract: OBJECTIVE
  The purpose of this study was to compare haemodynamics at rest and during exercise after clinically indicated aortic valve replacement (AVR) for aortic stenosis among patients randomly assigned to one of three haemodynamically excellent bioprostheses.
  
  
  METHODS
  In a single-centre, prospective trial, 60 patients undergoing clinically indicated AVR were randomly assigned to Freestyle, Magna Ease or Trifecta bioprostheses. Six months after surgery, patients underwent supine bicycle stress echocardiography for the assessment of aortic valve haemodynamics.
  
  
  RESULTS
  There were 5 protocol deviations from random valve assignments, and 4 patients did not return for follow-up stress echo, yielding a study group of 56 patients {17 Freestyle, 21 Magna Ease, 18 Trifecta; median age 70 [interquartile range (IQR) 63-78 years], 37 (66%) men}. There were no statistically significant differences between groups in valve size, concomitant procedures or exercise variables. Resting haemodynamics revealed significant differences between groups in mean gradient [Freestyle 7 (IQR 5-9) mmHg, Magna Ease 9 (IQR 7-11) mmHg, Trifecta 5 (IQR 4-8) mmHg; P = 0.04], effective orifice area (EOA) [2.5 (IQR 2.2-2.7), 2.1 (IQR 1.7-2.3) and 2.6 (IQR 2.3-2.8), respectively; P = 0.02] and EOA index [1.22 (IQR 1.11-1.32), 1.02 (IQR 0.89-1.14) and 1.31 (IQR 1.00-1.42), respectively; P = 0.03]; in each case, Trifecta had better haemodynamics compared with Magna Ease. With exercise, significant differences between groups were evident in peak velocity at 50 watts and peak exercise; mean gradient at 25 watts, 50 watts and maximal exercise; and EOA at 25 watts and at peak exercise; all with haemodynamic superiority of Trifecta compared with Magna Ease. There were no statistically significant differences between Trifecta and Freestyle haemodynamics at rest or with exercise.
  
  
  CONCLUSIONS
  In a prospective, randomized study comparing haemodynamics after Freestyle, Magna Ease and Trifecta, all three valves exhibited good haemodynamics at rest and with exercise. There were small but significant differences between groups, with favourable haemodynamics associated with Trifecta compared to Magna Ease, and no significant differences between Trifecta and Freestyle. The Trifecta valve appears to offer haemodynamics similar to a stentless valve without the technical complexity of stentless valve implantation.
  
  
  BACKGROUND
  NCT01635244.
authors.affiliation: Division of Cardiovascular Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA dbach@med.umich.edu.
authors.forename: David S
authors.initials: DS
authors.lastname: Bach
authors.affiliation: Division of Adult Cardiac Surgery, Department of Cardiac Surgery, University of Michigan, Ann Arbor, MI, USA.
authors.forename: Himanshu J
authors.initials: HJ
authors.lastname: Patel
authors.affiliation: Division of Cardiovascular Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA.
authors.forename: Theodore J
authors.initials: TJ
authors.lastname: Kolias
authors.affiliation: Division of Adult Cardiac Surgery, Department of Cardiac Surgery, University of Michigan, Ann Arbor, MI, USA.
authors.forename: G Michael
authors.initials: GM
authors.lastname: Deeb
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000000981:diagnostic imaging / Q000601:surgery*; D001024:Aortic Valve Stenosis / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D001705:Bioprosthesis; D015150:Echocardiography, Doppler; D025401:Echocardiography, Stress; D015444:Exercise / Q000523:psychology*; D005080:Exercise Test; D005260:Female; D005500:Follow-Up Studies; D006350:Heart Valve Prosthesis; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D011446:Prospective Studies; D011474:Prosthesis Design; D012720:Severity of Illness Index
keywords: Aortic valve replacement; Bioprosthesis; Echocardiography/Doppler; Exercise testing; Haemodynamics