Assessment of global left ventricular systolic function with multidetector CT and 2D echocardiography: a comparison between reconstructions of 1-mm and 2-mm slice thickness at multidetector CT

To compare multidetector computed tomography (MDCT) and two-dimensional transthoracic echocardiography (2DE) for left ventricular ejection fraction (EF); and to make comparison between reconstructions of 1-mm and 2-mm slice thickness at MDCT in left ventricular analysis by using a semiautomated segmentation algorithm. In 43 patients global left ventricular systolic function was assessed by using both MDCT and 2DE. Functional MDCT data sets were reconstructed in 20 cardiac phases (0-95%) with both 1-mm and 2-mm slice thickness.With semi-automatic left ventricle segmentation, end-diastolic volume (EDV), endsystolic volume (ESV) and EF were calculated seperately for both 1-mm and 2-mm reconstructions. On MDCT with 1-mm slice thickness, mean EF was 66.8 +/- 5.6 %, mean EDV was 133.7 +/- 38.9 mL, and mean ESV was 45.1 +/- 17.9 mL, these values for 2-mm slice thickness were 66.2 +/- 5.6 %, 133.5 +/- 39.6 mL, and 45.9 +/- 18.3 mL, respectively. On 2DE, mean EF was 66.7 +/- 5.7 %, mean EDV was 98.7 +/- 42.1 mL, and mean ESV was 33.6 +/- 18.7 mL. There was no difference between EF values calculated with 1-mm and 2-mm reconstructions and 2DE (P = 0.83 and P = 0.3705, respectively). However, EDV and ESV values calculated by MDCT were significantly higher than those obtained by 2DE (P < 0.0001). There was a good correlation between MDCT and 2DE in the evaluation of left ventricular EF. At MDCT left ventricular ESV was statistically smaller, EF was statistically greater by using 1-mm rather than 2-mm slice thickness. However, these differences are not clinically relevant.