title: Ejection fraction/velocity ratio identifies prosthesis-patient mismatches in patients with aortic bioprosthetic valves and left ventricular dysfunction.
abstract: OBJECTIVE
  Recently, a new echocardiographic nonflow corrected index (ejection fraction/velocity ratio [EFVR] = percent left ventricular ejection fraction [EF]/maximum aortic gradient) has been introduced and has shown excellent accuracy in quantifying the effective orifice area (EOA) in native aortic valves and bio-prostheses. The objective of this study was to assess the utility of the EFVR to quantify the indexed EOA in patients with an aortic bioprosthesis and left ventricular dysfunction considering an indexed EOA value of 0.85 cm(2)/m(2) or less to be indicative of a prosthesis-patient mismatch (PPM), defined as an EOA of the inserted prosthetic valve of less than that of the normal human valve.
  
  
  METHODS
  We studied 100 patients (62 men and 38 women; mean age +/- SD, 71 +/- 8.6 years) with an aortic bioprosthesis and left ventricular dysfunction (EF < or =49%), and we evaluated the indexed EOA by both the continuity equation (CE) and EFVR.
  
  
  RESULTS
  We found a significant linear correlation between the CE and EFVR (r = 0.85; P < .0001) and good agreement between the two methods in identifying patients with an indexed EOA of 0.85 cm(2)/m(2) or less; the correlation began to become nonlinear for patients with an indexed EOA of greater than 1.2 cm(2)/m(2), which was not clinically relevant. Notably, all 11 patients with a discrepancy between the indexed EOA and EFVR (ie, EFVR < or =1.0 and indexed EOA >0.85 cm(2)/m(2)) also showed an indexed EOA of greater than 0.85 but less than or equal to 1.0 cm(2)/m(2) (meaning the presence of a mild PPM).
  
  
  CONCLUSIONS
  The EFVR can be considered a reliable echocardiographic alternative to the CE, especially in conditions in which that is technically difficult, allowing identification of a PPM (indexed EOA < or =0.85 cm(2)/m(2)) with excellent sensitivity and specificity.
authors.affiliation: Department of Cardiology and Intensive Cardiac Rehabilitation, Istituto Di Ricovero e Cura a Carattere Scientifico Multimedica Holding, Castellanza VA, Italy. p.cattaneo@tin.it
authors.forename: Paolo
authors.initials: P
authors.lastname: Cattaneo
authors.forename: Massimo
authors.initials: M
authors.lastname: Baravelli
authors.forename: Andrea
authors.initials: A
authors.lastname: Rossi
authors.forename: Giovanni
authors.initials: G
authors.lastname: Mariscalco
authors.forename: Melania
authors.initials: M
authors.lastname: Romano
authors.forename: Daniela
authors.initials: D
authors.lastname: Imperiale
authors.forename: Alda
authors.initials: A
authors.lastname: Bregasi
authors.forename: Claudio
authors.initials: C
authors.lastname: Anzà
mesh_terms: D000368:Aged; D001021:Aortic Valve / Q000000981:diagnostic imaging*; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging* / Q000601:surgery*; D005260:Female; D006350:Heart Valve Prosthesis / Q000009:adverse effects*; D006801:Humans; D008297:Male; D011475:Prosthesis Failure; D013318:Stroke Volume; D016896:Treatment Outcome; D014463:Ultrasonography; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000209:etiology*