Abstract 15047: Quantitative Analysis of 1.5 T Whole Heart Coronary MR Angiography: Comparison with Conventional Quantitative Coronary Angiography
Background: Coronary MRA allows for noninvasive detection of significant coronary artery disease (CAD). However, visual assessment of coronary MRA is observer dependent. The purposes of this study were to develop a new methods (MR-QCA) to determine stenosis severity on whole heart coronary MRA, and to evaluate the accuracy of this approach for detecting significant CAD by using conventional quantitative coronary angiography (QCA) as a reference method.
Methods: Sixty-two patients with suspected CAD (age 69±13 years) underwent 1.5T non-contrast enhanced whole heart coronary MRA using 32-channel coils. After generating maximum intensity projection images along each coronary artery and performing background signal correction, percent stenosis was measured by computing the signal intensity profile along the vessel. X-ray coronary angiograms were analyzed with use of QCA software by blinded observers.
Results: Diagnostic coronary MRA images were obtained within 10 minutes in all patients. Percent stenoses quantified by MR-QCA showed a high linear correlation with those by QCA (R=0.84). In addition, percent stenoses quantified by MR-QCA showed a good inter-observer agreement (R=0.99) with a mean absolute difference of 4.0%. ROC analysis revealed that the optimal threshold in predicting stenosis >50% on conventional QCA was 35% for MR-QCA. MR-QCA demonstrated the sensitivity of 90% (52/58), specificity of 91% (361/397), PPV of 59% (52/88) and NPV of 98% (361/367) on a segment based analysis. These values were 90% (44/49), 80% (109/137), 61% (44/72) and 96% (109/114) on a vessel based analysis, respectively.
Conclusions: MR-QCA analysis of whole heart coronary MRA permits more Objectives and reproducible assessment of CAD in comparison with visual evaluation. High NPV (96%) observed in this study indicated that whole heart coronary MRA assessed by MR-QCA is useful for ruling out significant CAD.
- © 2010 by American Heart Association, Inc.