title: Validation of Transesophageal Echocardiographic In Vitro Measurements for Bioprosthetic Aortic Valves: Implications for Percutaneous Valve-in-Valve Therapy.
abstract: BACKGROUND
  Percutaneous valve-in-valve therapy has become an important treatment option for failing bioprosthetic heart valves. Accurate assessment of valve internal diameter (ID) is essential for effective and safe treatment. These data may not be available in an individual patient, or the manufacturer-supplied dimensions may be incorrect because they do not allow for the space occupied by valve leaflet material.
  
  
  METHODS
  In total, 2,332 two-dimensional and three-dimensional transesophageal echocardiographic in vitro measurements were performed using both Philips iE33 and GE Vivid E9 systems with a range of system settings on 53 bioprosthetic valves in all available sizes. Two-dimensional echocardiographic ID measurements were made in two orthogonal planes at the level of the sewing ring, and similar three-dimensional measurements were generated from multiplane reconstructions. They were compared with both manufacturer-supplied valve ID (MID) and the true ID (TID) measured with Hegar dilators.
  
  
  RESULTS
  Both the iE33 and the Vivid 9 provided comparable valve ID measurements. TID was statistically significantly smaller than MID (P < .001). All echocardiographic measurements were closer to TID than to MID. Two-dimensional measurements were closest to TID because of higher spatial resolution.
  
  
  CONCLUSIONS
  Transesophageal echocardiographic valve ID measurements compare well with TID, which is overestimated by MID. These findings have potentially important implications for valve-in-valve procedures because an inaccurate measurement of TID might lead to the wrong choice of implanted valve.
authors.affiliation: Department of Non Invasive Cardiology, King's College Hospital, London, United Kingdom.
authors.forename: Fortunata
authors.initials: F
authors.lastname: Condemi
authors.affiliation: Department of Cardiothoracic Surgery, St Thomas' Hospital, London, United Kingdom.
authors.forename: Vinnie N
authors.initials: VN
authors.lastname: Bapat
authors.affiliation: Department of Non Invasive Cardiology, King's College Hospital, London, United Kingdom.
authors.forename: Silvia
authors.initials: S
authors.lastname: Gianstefani
authors.affiliation: Department of Non Invasive Cardiology, King's College Hospital, London, United Kingdom.
authors.forename: Norman
authors.initials: N
authors.lastname: Catibog
authors.affiliation: Department of Non Invasive Cardiology, King's College Hospital, London, United Kingdom.
authors.forename: Alexandros
authors.initials: A
authors.lastname: Papachristidis
authors.affiliation: King's College, London, United Kingdom.
authors.forename: Abdel
authors.initials: A
authors.lastname: Douiri
authors.affiliation: Department of Cardiology, University of Tor Vergata, Rome, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Romeo
authors.affiliation: Department of Non Invasive Cardiology, King's College Hospital, London, United Kingdom. Electronic address: mark.monaghan@nhs.net.
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Monaghan
mesh_terms: D001021:Aortic Valve / Q000000981:diagnostic imaging* / Q000601:surgery*; D001705:Bioprosthesis; D017548:Echocardiography, Transesophageal / Q000295:instrumentation / Q000379:methods*; D019544:Equipment Failure Analysis; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D019047:Phantoms, Imaging; D011474:Prosthesis Design; D017755:Prosthesis Fitting / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D025321:Surgery, Computer-Assisted / Q000379:methods; D016896:Treatment Outcome
keywords: Failed aortic bioprosthesis; Internal diameter measurement; Ultrasound imaging; Valve-in-valve implantation