Abstract 4215: Defining the Best Approach for Stenosis Quantification by Dual-Source CT - A Comparative Study Involving Intravascular Ultrasound and Invasive Coronary Angiography
Background: Dual-source computed tomography (DSCT) permits reliable noninvasive detection of coronary stenosis based on qualitative visual assessment. The purpose of this study was to determine the accuracy of DSCT to quantify the degree of coronary stenosis and minimal lumen area (MLA) and diameter (MLD) as compared to quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS), based on the unique opportunity of coronary CT to simulate both methods.
Methods: We prospectively enrolled 21 patients scheduled for clinically indicated invasive coronary angiography (mean age 62 ± 9, 70% men) who underwent DSCT and IVUS as a part of research study. No segments were excluded from the analysis. Two readers calculated the degree of stenosis by DSCT blinded to QCA and IVUS. DSCT luminal diameters and areas were measured in cross-sectional reformatted images created perpendicular to the centerline of the vessel.
Results: Table 1⇓ demonstrates all results obtained. The mean degree of stenosis assessed by DSCT was better expressed in area as compared to diameter and also had a better correlation with IVUS then with QCA (r=0.73 and r=0.6, respectively). Bland-Altman analysis demonstrated a positive bias for quantification of stenosis by DSCT using diameter criteria, as compared to both modalities QCA and IVUS, (+ 4 % and + 9.1%, respectively). A negative bias was introduced when percentage stenosis area was quantified by DSCT and compared to IVUS (− 5,8 %). MLD defined by DSCT was also better correlated with IVUS when compared to QCA (r=078 and r=0.59, respectively), and better expressed in area (MLA) then diameter (r=0.9 and 0.78, respectively). Quantification of vessel remodeling also reached a good correlation with IVUS (r=0.65).
Conclusion: Overall, DSCT allows better comparison to IVUS then QCA to calculate the degree of stenosis. An excellent MLA correlation was obtained between DSCT and IVUS and this can have important practical clinical applications.