Objective: To determine the interobserver reliability for grading coronary stenosis severity with coronary computed tomographic angiography (CCTA).
Methods: Five readers independently reviewed 40 CCTA studies, first the axial images alone, then in combination with multiplanar reconstructions. The stenosis severity in each segment was scored on a 5-point scale. Intraclass correlation (ICC) analysis was performed to assess interobserver reliability on a segmental basis.
Results: The reliability was good to moderate in the right coronary artery, left main artery, left anterior descending artery and branches, and the proximal circumflex (ICC: 0.44-0.75) but fair to poor for the posterior descending artery, the posterolateral branch, the obtuse marginal branches, and the distal circumflex (ICC: 0.15-0.39). The ICC correlated with the reference diameter. Although there was no significant difference in the ICC between the scanner types, there were more unevaluable segments in the 16-row scanner compared with the 64-row scanner (2.4 vs 1.4 segments/patient). Addition of multiplanar reconstruction to axial images led to fewer uninterpretable segments and reclassification of stenosis grade in 23% of the segments.
Conclusions: Interobserver reliability for stenosis severity by CCTA varies between segments and correlates with the reference diameter.
From the *Division of Cardiology, Providence Veterans Affairs Medical Center, Providence, Rhode Island; †Departments of Medicine, and ‡Diagnostic Imaging, Rhode Island Hospital, Warren Alpert School of Medicine of Brown University, Providence, RI.
Received for publication May 18, 2010; accepted August 16, 2010.
Reprints: Gaurav Choudhary, MD, 830 Chalkstone Ave, Providence, RI 02908 (e-mail: firstname.lastname@example.org).
This material is based on work supported by the Department of Veterans Affairs, Veterans Health Administration, Office of Research and Development: Biomedical Laboratory Research and Development Service (CDA-2 Award to G.C.); Research Enhancement Award Program grant (TRP 04-179) from the Health Services Research and Development Service (W.-C.W.). The views expressed in this article are those of the authors and do not necessarily reflect the position or policy of the Department of Veterans Affairs.