title: Assessment of paravalvular aortic regurgitation after transcatheter aortic valve replacement: intra-core laboratory variability.
abstract: BACKGROUND
  There is significant disparity in the reported incidence of moderate and severe paravalvular aortic regurgitation (PAR) between the Placement of Aortic Transcatheter Valves (PARTNER) I and PARTNER II trials, which may be related to the echocardiographic methodologies used by separate core laboratories. To further explore the variability in echocardiographic interpretation of PAR, agreement between the grading of PAR by the core laboratory of PARTNER IIB was compared with that by a consortium of echocardiography core laboratory directors.
  
  
  METHODS
  The PARTNER IIB core laboratory reevaluated patients using primarily the circumferential extent of the regurgitant jet for PAR. A consortium of echocardiography core laboratory directors was formed to evaluate the echocardiographic images and to grade PAR and central and total aortic regurgitation in a randomly chosen subset of the randomized patients in the PARTNER IIB trial using a multiwindow, multiparametric approach. Both a four-class scale (none or trace, mild, moderate, and severe) and a seven-class (none, trace, mild, mild to moderate, moderate, moderate to severe, and severe) scale were used. Levels of grading agreement between the consortium and original core laboratory in both scales were determined using weighted κ statistics.
  
  
  RESULTS
  Only 87 patients assessed for PAR by the consortium could be paired with readings by the PARTNER IIB core laboratory. Using the four-class grading scheme the weighted κ statistic for PAR was 0.481 (95% confidence limits, 0.367, 0.595). Using the seven-class scale, the weighted κ statistic for PAR was 0.517 (95% confidence limits, 0.431, 0.607). For either grading scheme, 15.9% of patients graded by the PARTNER IIB core laboratory as having moderate PAR would have been graded as having mild PAR using the multiparametric approach. Similar results were seen for central and total aortic regurgitation assessments.
  
  
  CONCLUSIONS
  Using primarily the circumferential extent criteria, the PARTNER IIB core laboratory overestimated the severity of PAR compared to the consortium using a multi-parametric approach. Although a more granular classification scheme for PAR may slightly improve concordance between core laboratories, differences in the incidence of moderate or severe PAR are likely related to differences in grading methodology. A multiparametric approach is advocated, and other echocardiographic methods for assessing PAR deserve further study.
authors: Columbia University Medical Center/New York-Presbyterian Hospital, New York, New York. Electronic address: rth2@columbia.edu.
authors: Rebecca T
authors: RT
authors: Hahn
authors: Québec Heart and Lung Institute, Laval University, Québec City, Québec, Canada.
authors: Philippe
authors: P
authors: Pibarot
authors: Medstar Health Research Institute, Washington, District of Columbia.
authors: Neil J
authors: NJ
authors: Weissman
authors: Cleveland Clinic Foundation, Cleveland, Ohio.
authors: Leonardo
authors: L
authors: Rodriguez
authors: Cleveland Clinic Foundation, Cleveland, Ohio.
authors: Wael A
authors: WA
authors: Jaber
mesh_terms: D000369:Aged, 80 and over; D001022:Aortic Valve Insufficiency / Q000000981:diagnostic imaging* / Q000209:etiology*; D001024:Aortic Valve Stenosis / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery*; D005260:Female; D006801:Humans; D007755:Laboratories, Hospital; D008297:Male; D015588:Observer Variation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D065467:Transcatheter Aortic Valve Replacement / Q000009:adverse effects*; D016896:Treatment Outcome; D014463:Ultrasonography; D014481:United States
keywords: Aortic stenosis; Paravalvular regurgitation; TAVI; TAVR