Functional parameters of the left ventricle: comparison of cardiac MRI and cardiac CT in a large population

The authors sought to compare magnetic resonance imaging (MRI) and computed tomography (CT) for assessing left ventricular (LV) function parameters in a large patient population. The study was conducted on 181 patients who underwent cardiac MRI and cardiac CT for various indications. For MRI, we used two-dimensional cine balanced steady-state free precession (b-SSFP) sequences, and for CT we used multiphase short-axis reconstructions. Volume data sets were evaluated with dedicated software. Results were compared with a paired, two-tailed Student's t test, Pearson's correlation (r), and Bland-Altman analysis. A high level of concordance was observed between cardiac MRI and CT. Ejection fraction (EF) was 53 +/- 14% for MRI vs. 53%+/- 15% for CT. There was good correlation for EF (r=0.71; p > 0.05) and end-systolic volume (r=0.74; p > 0.05). End-diastolic volume (74 +/- 23 ml at MRI vs. 71 +/- 19 ml at CT; r=0.58; p < 0.05) and myocardial mass (63 +/- 20 g at MRI and 56 +/- 18 g at CT; r=0.89; p < 0.01) showed statistically significant differences, although the discrepancy had no clinical impact. MRI and CT show a good level of agreement in assessing LV function parameters, and both can be used interchangeably in clinical practice.