title: Hemolysis parameters of St. Jude Medical: Hemodynamic Plus and Regent valves in aortic position.
abstract: BACKGROUND
  Elevated plasma lactate dehydrogenase (LDH) concentration may reflect hemolysis due to mechanical heart valve dysfunction. Thus, knowledge of LDH levels in patients with properly working prostheses is required. Because hemolysis parameters for the SJM Hemodynamic Plus (HP) and Regent series are currently not available, the purpose of our study was to determine these data.
  
  
  METHODS
  At 12-19 months follow-up after isolated aortic valve replacement with SJM HP(R) or Regent prostheses, we examined 102 patients by transthoracic echocardiography and determined plasma LDH, haptoglobin, bilirubin and hemoglobin.
  
  
  RESULTS
  Five patients with properly working prostheses were excluded because of increased LDH due to non-cardiac reasons. In four patients with paravalvular leakage, LDH was 244, 307, 446 and 628 U/l, respectively. In patients with properly working prostheses, LDH was 287+/-52 (range: 163-374) U/l for HP(R) (n=33) and 274+/-48 (151-386) U/l for Regent valves (n=60, p=0.2). Haptoglobin was <1g/l in all patients; in 91% of HP and 75% of Regent valves, haptoglobin was below detection limit. Bilirubin and hemoglobin as well as red blood cell count (RBC) were normal in all patients except for five patients with renal anemia, two patients with paravalvular leakage and four patients with macrocytosis due to alcohol abuse. There was no correlation between LDH and transvalvular gradient (r=-0.02) or valve size (r=0.25).
  
  
  CONCLUSIONS
  In patients with SJM HP(R) or Regent valves in aortic position, LDH values > 400 U/l indicate valvular dysfunction or leakage if non-cardiac causes for hemolysis are excluded. However, paravalvular leakage can be present without substantially increased LDH. Haptoglobin has no diagnostic value as it is almost always markedly reduced. Hemolysis does not correlate with transvalvular gradient or prosthesis size.
authors.affiliation: Department of Cardiothoracic Surgery, University of Cologne, Joseph-Stelzmann-Str. 9, 50924 Cologne, Germany. michael.suedkamp@medizin.uni-koeln.de
authors.forename: Michael
authors.initials: M
authors.lastname: Suedkamp
authors.forename: Aurelia J
authors.initials: AJ
authors.lastname: Lercher
authors.forename: Falk
authors.initials: F
authors.lastname: Mueller-Riemenschneider
authors.forename: Karl
authors.initials: K
authors.lastname: LaRosee
authors.forename: Paschalis
authors.initials: P
authors.lastname: Tossios
authors.forename: Uwe
authors.initials: U
authors.lastname: Mehlhorn
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000378:metabolism* / Q000601:surgery*; D001024:Aortic Valve Stenosis / Q000378:metabolism / Q000601:surgery; D001663:Bilirubin / Q000097:blood; D015415:Biomarkers / Q000097:blood; D002315:Cardiopulmonary Bypass; D004912:Erythrocytes / Q000378:metabolism; D005260:Female; D005500:Follow-Up Studies; D006242:Haptoglobins / Q000378:metabolism; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation; D006454:Hemoglobins / Q000378:metabolism; D006461:Hemolysis / Q000502:physiology*; D006801:Humans; D019934:International Normalized Ratio; D007770:L-Lactate Dehydrogenase / Q000097:blood; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000209:etiology / Q000378:metabolism; D011474:Prosthesis Design; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D006242:Haptoglobins; D006454:Hemoglobins; D007770:L-Lactate Dehydrogenase; D001663:Bilirubin