title: Early in vivo experience with the Hemodynamic Plus St. Jude Medical heart valves in patients with narrowed aortic annulus.
abstract: BACKGROUND
  Small aortic orifice primarily resulted in heart prosthesis mismatch in a significant number of patients. The Hemodynamic Plus (HP) series of St. Jude Medical heart valves represents an interesting innovation, allowing a larger valve orifice area with an equivalent tissue annulus diameter.
  
  
  METHODS
  Hemodynamic characteristics of the 21-mm HP St. Jude Medical valve were prospectively compared with those of the standard 21-mm and 23-mm St. Jude Medical valves in three groups of 22 patients. Patients were selected from a database to be rigorously matched for age, sex, body surface area, functional class, underlying lesion, native valve opening area, left ventricular function, and preoperative peak and mean valve gradients. Postoperative evaluation (follow-up ranging from 3 to 24 months; mean, 11.5 months) included clinical examination and echocardiographic studies.
  
  
  RESULTS
  There was no operative mortality or significant perioperative complications. Short-term clinical follow-up was marked by a complete absence of valve-related complications. Presently, all but 1 patient in the 21-mm HP group and 2 in the 21-mm standard group are in New York Heart Association functional class I. Doppler echocardiography-derived mean and maximal pressure gradients were significantly lower in the 21-mm HP group (8.1 +/- 1.9 and 16.4 +/- 3.4 mm Hg) than in the 21-mm standard group (13.4 +/- 3.9 and 21.2 +/- 4.3 mm Hg; p = 0.002 and p = 0.0004, respectively), confirming the better hemodynamic performance already described in in vitro studies. Pressure gradients did not differ significantly between the 21-mm HP and the 23-mm standard groups. The 21-mm HP valve demonstrated the highest performance index; 0.66 +/- 0.08, compared with 0.49 +/- 0.09 for the 21-mm standard valve (p < 0.001) and 0.59 +/- 0.07 for the 23-mm standard valve (p < 0.001).
  
  
  CONCLUSIONS
  In vivo hemodynamic performance of the 21-mm HP valve corresponds closely to that of the 23-mm standard valve and is substantially better than that of the 21-mm standard valve. The 21-mm HP St. Jude Medical valve demonstrates excellent hemodynamic characteristics and can be recommended in normal-sized adult patients with narrow aortic root. This valve will minimize the need for aortic annulus enlargement.
authors.affiliation: Clinic for Cardiovascular Surgery, University Hospital, Zürich, Switzerland.
authors.forename: T
authors.initials: T
authors.lastname: Carrel
authors.forename: U
authors.initials: U
authors.lastname: Zingg
authors.forename: R
authors.initials: R
authors.lastname: Jenni
authors.forename: B
authors.initials: B
authors.lastname: Aeschbacher
authors.forename: M I
authors.initials: MI
authors.lastname: Turina
mesh_terms: D000328:Adult; D001024:Aortic Valve Stenosis / Q000601:surgery*; D006350:Heart Valve Prosthesis / Q000295:instrumentation*; D006439:Hemodynamics; D006801:Humans; D011446:Prospective Studies; D011474:Prosthesis Design