Diagnostic accuracy of CT for the detection of left ventricular myocardial fibrosis in various myocardial diseases.

PURPOSE: To evaluate the diagnostic accuracy of computed tomography (CT) for the detection of myocardial fibrosis, we compared the frequency of abnormal late enhancement (LE) in left ventricular myocardium (LVM) on CT with that on gadolinium-enhanced cardiac magnetic resonance (CMR) in patients with various myocardial diseases.

METHODS: Fifty-six patients with suspected various myocardial diseases (19 with hypertrophic cardiomyopathy, 3 with cardiac amyloidosis, 3 with post myocarditis, 2 with dilated cardiomyopathy, 2 with cardiac sarcoidosis, 2 with cardiac tumor, 2 with previous myocardial infarction, 2 with hypertensive heart disease) underwent 1.5-T CMR and cardiac CT within 2months without clinical accidents.

RESULTS: LE on LVM was detected in 31 and 31 patients on CT and CMR, respectively, and in 192 and 197 LVM segments on CT and CMR, respectively, among a total of 952 LVM segments. The sensitivity, specificity, positive and negative predictive values, and consistency for detection of LE on CT in comparison with CMR were 90, 89, 90, 89 and 89%, respectively, on patient-based analysis, and 67, 92, 68, 91 and 87%, respectively, on segment-based analysis. Inter-observer agreement for detection of LE on CT was 0.71 (kappa coefficient), and it was significantly lower than that on CMR (0.82) on segment-based analysis (P<0.05).

CONCLUSIONS: Compared with CMR, diagnostic accuracy of CT for the evaluation of LE in LVM in patients with myocardial diseases was relatively higher on patient-based analysis, but was limited on segment-based analysis, and the inter-observer agreement on CT was significantly lower than that on CMR.