title: Multidetector-row computed tomography allows accurate measurement of mechanical prosthetic heart valve leaflet closing angles compared with fluoroscopy.
abstract: OBJECTIVE
  The purpose of this study was to compare multidetector-row computed tomography (MDCT) leaflet restriction measurements with fluoroscopy measurements in commonly used mechanical prosthetic heart valves (PHVs).
  
  
  METHODS
  Four mechanical PHVs (ON-X, Carbomedics, St. Jude, and Medtronic Hall) were imaged in a pulsatile model using fluoroscopy and 64-detector-row computed tomography. Five image acquisitions of each PHV without (1) and with (4) restricted leaflet closure were made. Three observers measured closure angles on fluoroscopy and MDCT. Data were analyzed using intraclass correlation coefficient (ICC) and Bland-Altman plots.
  
  
  RESULTS
  Interobserver agreement was high in restricted and non-restricted leaflets on both modalities (ICCs >0.995). MDCT and fluoroscopy showed high agreements (ICCs >0.989). Median MDCT closure angle measurements differed at most -2 to +2 degrees from fluoroscopy in the restricted and -1 to +2 degrees in the non-restricted leaflets.
  
  
  CONCLUSIONS
  MDCT allows measurement of leaflet motion with a maximal median discrepancy of 2 degrees. Both MDCT and fluoroscopy detect restricted leaflet closure with great accuracy.
authors.affiliation: From the *Department of Radiology, University Medical Center Utrecht, Utrecht; †Department of Cardiothoracic Surgery, Academic Medical Center Amsterdam, Amsterdam; and ‡Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Dominika
authors.initials: D
authors.lastname: Suchá
authors.forename: Petr
authors.initials: P
authors.lastname: Symersky
authors.forename: Evert-Jan P A
authors.initials: EJ
authors.lastname: Vonken
authors.forename: Esther
authors.initials: E
authors.lastname: Provoost
authors.forename: Steven A J
authors.initials: SA
authors.lastname: Chamuleau
authors.forename: Ricardo P J
authors.initials: RP
authors.lastname: Budde
mesh_terms: D019544:Equipment Failure Analysis / Q000379:methods; D005471:Fluoroscopy / Q000295:instrumentation / Q000379:methods*; D006350:Heart Valve Prosthesis; D006351:Heart Valves / Q000000981:diagnostic imaging* / Q000601:surgery*; D006801:Humans; D061330:Multidetector Computed Tomography / Q000295:instrumentation / Q000379:methods*; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity