Abstract 13306: Quantitative Measurement of Abnormal Late Enhancement Volume in the Left Ventricular Myocardium in Myocardial Diseases by Multidetector-Row CT (CT) Compared to Cardiac Magnetic Resonance: Segmental Analysis
Purpose: To measure late enhancement (LE) volume (LEV) in diseased left ventricular myocardium (LVM) using MDCT and to compare LEV measured by MDCT with LEV measured by magnetic resonance (MR).
Materials and Methods: Forty subjects (29 male, mean age 62.5±10.8 years) with suspected LV myocardial abnormalities (23 hypertrophic and 5 dilated cardiomyopathy, 1 cardiac sarcoidosis, and others) underwent enhanced CT (Aquilion one, Toshiba or Light Speed Ultra 16, GE) and MR (Intera Achieva 1.5T, Philips) within 3 months. Six and 15 minutes after injection of contrast medium, late-phase acquisitions were obtained with both CT and MR. In CT, sites which revealed contrast defects in the early phase were evaluated and if they were abnormally enhanced in the late phase, we characterized them as LE. The presence of LE was recorded in each of 17 LVM segments based on American Heart Association guidelines, and total LEV was measured in each modality.
Results: LE was detected in 238 segments from 40 subjects (113 segments by both CT, and MR, 65 segments by CT only, and 60 segments by MR). The sensitivity, specificity, positive and negative predictive values, and consistency for detection of LE by CT in comparison with MR were 65.3, 87.2, 63.5, 88.4 and 81.6%, respectively. Inter-observer agreement for detection of LE was 0.81 in CT and 0.83 in CMR. LEV was 23.4±29.7ml and 20.8±30.0ml when measured by CT and MR, respectively. This difference was not significant (P=0.36). Correlation between CT and MR measurements was string (R=0.75, P<0.01). Using Bland Altman analysis, the mean difference ±2SD in LEV between CT and MR was 2.60±42.13ml.
Conclusions: CT measurements of LE have excellent consistency and correlation with MR. Clinical Relevance: CT may be a useful tool in addition to MR for the detection of LE and the measurement of LEV quantitatively in subjects with LVM abnormalities by adding late phase acquisition. When compared to MR, CT may underestimate LEV.
- © 2010 by American Heart Association, Inc.