Jean-Pierre Laissy MD, PhD, Presenter: Nothing to Disclose

Pascal Guéret, Abstract Co-Author: Nothing to Disclose

Laurent Bonello, Abstract Co-Author: Nothing to Disclose

Alexis Jacquier MD, Abstract Co-Author: Nothing to Disclose

Jean-François Deux, Abstract Co-Author: Nothing to Disclose

Gilles Chatellier, Abstract Co-Author: Nothing to Disclose

Jean-Nicolas Dacher MD, PhD, Abstract Co-Author: Consultant, General Electric Company

Christophe Tron, Abstract Co-Author: Nothing to Disclose

Luc Christiaens, Abstract Co-Author: Nothing to Disclose

Michèle Hamon MD, Abstract Co-Author: Nothing to Disclose

Vincent Lepennec, Abstract Co-Author: Nothing to Disclose

Laurent Leborgne, Abstract Co-Author: Nothing to Disclose

Cédric Renard, Abstract Co-Author: Nothing to Disclose

Christophe Caussin, Abstract Co-Author: Nothing to Disclose

Jean-Francois Paul MD, Abstract Co-Author: Advisory Board, Guerbet SA Speaker, Guerbet SA Speaker, Siemens AG Consultant, Bayer AG

Dominique Crochet, Abstract Co-Author: Nothing to Disclose

Valerie Chantal Chabbert-Durand MD, Abstract Co-Author: Nothing to Disclose

Francis Joffre, Abstract Co-Author: Nothing to Disclose

To test if the diagnostic performance of coronary CT angiography (CTCA) to detect or exclude significant coronary artery disease (CAD) is influenced by methodologic choice of nonassessable segments , whether they are considered normal or stenosed.

A large national multicenter prospective study was conducted in stable symptomatic patients referred to 40 national sites for non emergent coronary angiography (CA) . CTCA and CA data were blindly analysed at central core laboratories. No patients or coronary segments were excluded because of impaired image quality, vessel size, calcium score, body mass index. Nonassessable segments by CTCA were counted as positive for CAD. Patient -based diagnostic performances (sensitivities, specificities, positive and negative predictive values, positive and negative likelihood ratios) to detect or rule out significant CAD were evaluated. Multivariate regression analysis was used to exhibit the independent factors related to nonassessable segments

A total of 1062 patients (mean age 61+12y, 70.3% men) underwent both CTCA and CA. CTCA was performed 1.7 + 0.7 days before CA. In this cohort, 785 patients (73.9%) were referred to a ≥ 64-detector scanner. The prevalence of significant CAD was 52.3%. The rate of nonassessable segments by CTCA was 8.6% (12.2% with <64 detectors, 7.7% with ≥64 detectors). In a patient-based analysis, the sensitivity, specificity, positive and negative predictive values and positive and negative likelihood ratios were 91%, 52%, 67%, 84%, 1.88 and 0.17, respectively. The strongest predictors of non-assessable segments (p < 0.001) were vessel size <1.5mm (odd ratio OR, 12.34),  presence of artifacts (OR, 4.45), arrhythmia (OR, 1.58), number of CT detectors (OR, 2.43), calcium score > 400 (OR, 1.4), heart rate > 65/mn (OR, 1.3), body mass index (OR, 1.58).

In this prospective multicenter study conducted in stable patients with chest pain, CTCA identifies significant CAD with a high sensitivity. Diagnostic performance is influenced by the prevalence of nonassessable segments, considered as stenosed in the present study. The knowledge of these predictors can help better selection of patients referred to CTCA examinations.

The knowledge of factors resulting in nonassessable coronary segments at CT may improve selection of patients with suspected coronary artery disease referred to CTCA examinations.

Laissy, J, Guéret, P, Bonello, L, Jacquier, A, Deux, J, Chatellier, G, Dacher, J, Tron, C, Christiaens, L, Hamon, M, Lepennec, V, Leborgne, L, Renard, C, Caussin, C, Paul, J, Crochet, D, Chabbert-Durand, V, Joffre, F, Influence of Clinical and Technical Parameters on the Accuracy of Coronary CT Angiography: Results of Multivariate Regression Analysis from the Prospective National Multicenter EVASCAN Study.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11008227.html