title: LV thrombus detection by routine echocardiography: insights into performance characteristics using delayed enhancement CMR.
abstract: OBJECTIVE
  This study sought to evaluate performance characteristics of routine echo for left ventricular thrombus (LVT).
  
  
  BACKGROUND
  Although the utility of dedicated echocardiography (echo) for LVT is established, echo is widely used as a general test for which LVT is rarely the primary indication. We used delayed-enhancement cardiac magnetic resonance (DE-CMR) as a reference to evaluate LVT detection by routine echo.
  
  
  METHODS
  Dedicated LVT assessment using DE-CMR was prospectively performed in patients with left ventricular systolic dysfunction. Echoes were done as part of routine clinical care. Echo and CMR were independently read for LVT and related indexes of LVT size, shape, and image quality/diagnostic confidence. Follow-up was done for embolic events and pathology validation of LVT.
  
  
  RESULTS
  In this study, 243 patients had routine clinical echo and dedicated CMR within 1 week without intervening events. Follow-up supported DE-CMR as a reference standard, with >5-fold difference in endpoints between patients with versus without LVT by DE-CMR (p = 0.02). LVT prevalence was 10% by DE-CMR. Echo contrast was used in 4% of patients. Echo sensitivity and specificity were 33% and 91%, with positive and negative predictive values of 29% and 93%. Among patients with possible LVT as the clinical indication for echo, sensitivity and positive predictive value were markedly higher (60%, 75%). Regarding sensitivity, echo performance related to LVT morphology and mirrored cine-CMR, with protuberant thrombus typically missed when small (p ≤ 0.02). There was also a strong trend to miss mural thrombus irrespective of size (p = 0.06). Concerning positive predictive value, echo performance related to image quality, with lower diagnostic confidence scores for echoes read positive for LVT in discordance with DE-CMR compared with echoes concordant with DE-CMR (p < 0.02).
  
  
  CONCLUSIONS
  Routine echo with rare contrast use can yield misleading results concerning LVT. Echo performance is improved when large protuberant thrombus is present and when the clinical indication is specifically for LVT assessment.
authors.affiliation: Duke Cardiovascular Magnetic Resonance Center, Duke University Medical Center, Durham, North Carolina 27710, USA.
authors.forename: Jonathan W
authors.initials: JW
authors.lastname: Weinsaft
authors.forename: Han W
authors.initials: HW
authors.lastname: Kim
authors.forename: Anna Lisa
authors.initials: AL
authors.lastname: Crowley
authors.forename: Igor
authors.initials: I
authors.lastname: Klem
authors.forename: Chetan
authors.initials: C
authors.lastname: Shenoy
authors.forename: Lowie
authors.initials: L
authors.lastname: Van Assche
authors.forename: Rhoda
authors.initials: R
authors.lastname: Brosnan
authors.forename: Dipan J
authors.initials: DJ
authors.lastname: Shah
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Velazquez
authors.forename: Michele
authors.initials: M
authors.lastname: Parker
authors.forename: Robert M
authors.initials: RM
authors.lastname: Judd
authors.forename: Raymond J
authors.initials: RJ
authors.lastname: Kim
mesh_terms: D000368:Aged; D016009:Chi-Square Distribution; D003287:Contrast Media; D004452:Echocardiography; D005260:Female; D006331:Heart Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012042:Registries; D013927:Thrombosis / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology; D016277:Ventricular Function, Left
chemical_list: D003287:Contrast Media