Quantitative assessment of left ventricular function with dual-source CT in comparison to cardiac magnetic resonance imaging: initial findings

Abstract

Cardiac magnetic resonance imaging and echocardiography are currently regarded as standard modalities for the quantification of left ventricular volumes and ejection fraction. With the recent introduction of dual-source computedtomography (DSCT), the increased temporal resolution of 83 ms should also improve the assessment of cardiac function in CT. The aim of this study was to evaluate the accuracy of DSCT in the assessment of left ventricular functional parameters with cardiac magnetic resonance imaging (MRI) as standard of reference. Fifteen patients (two female, 13 male; mean age 50.8 +/- 19.2 years) underwent CT and MRI examinations on a DSCT (Somatom Definition; Siemens Medical Solutions, Forchheim, Germany) and a 3.0-Tesla MR scanner (Magnetom Trio; Siemens Medical Solutions), respectively. Multiphase axial CT images were analysed with a semiautomatic region growing algorithms (Syngo Circulation; Siemens Medical Solutions) by two independent blinded observers. In MRI, dynamic cine loops of short axis slices were evaluated with semiautomatic contour detection software (ARGUS; Siemens Medical Solutions) independently by two readers. End-systolic volume (ESV), end-diastolic volume (EDV), ejection fraction (EF) and stroke volume (SV) were determined for both modalities, and correlation coefficient, systematic error, limits of agreement and inter-observer variability were assessed. In DSCT, EDV and ESV were 135.8 +/- 41.9 ml and 54.9 +/- 29.6 ml, respectively, compared with 132.1 +/- 40.8 ml EDV and 57.6 +/- 27.3 ml ESV in MRI. Thus, EDV was overestimated by 3.7 ml (limits of agreement -46.1/+53.6), while ESV was underestimated by 2.6 ml (-36.6/+31.4). Mean EF was 61.6 +/- 12.4% in DSCT and 57.9 +/- 9.0% in MRI, resulting in an overestimation of EF by 3.8% with limits of agreement at -14.7 and +22.2%. Rank correlation rho values were 0.81 for EDV (P = 0.0024), 0.79 for ESV (P = 0.0031) and 0.64 for EF (P = 0.0168). The kappa value of inter-observer variability were amounted to 0.85 for EDV, ESV and EF. DSCT offers the possibility to quantify left ventricular function from coronary CT angiography datasets with sufficient diagnostic accuracy, adding to the value of the modality in a comprehensive cardiac assessment. The observed differences in the measured values may be due to different post-processing methods and physiological reactions to contrast material injection without beta-blocker medication.

Value of dual-source computed tomography in evaluating left ventricular function in patients with coronary heart disease

“…In addition, emergency patients and those with heart pacemakers or metallic foreign bodies cannot be routinely examined by MRI. Domestic and foreign scholars (Yamamuro et al, 2005;Busch et al, 2008) used the results of MRI measurement on cardiac function as a standard with which to comparemulti-slice spiral CT MSCT and echocardiography in the measurement of left ventricular function. They found that MSCT is more accurate and reliable than ultrasound measurements of left ventricular function, and that spatial resolution in CT images is superior to MRI, allowing the inner and outer membrane profile of heart, myocardium, and its accessory structure to be displayed more clearly, and facilitating tracing the inner and outer membrane profiles of the heart.…”

Evaluation of global left ventricular function assessment by dual-source computed tomography compared with MRI

“…A recent study using a moving heart-phantom by Mahnken et al [18] showed a good correlation between DSCT and MRI, with no significant differences, which is in accordance to the present in-vivo study. Only two small studies in patients are available at the present time [19,20]. A striking difference between the two studies is the wide B-A interval in the study by Busch et al [20] in which two different post-processing softwarepackages have been implemented for the MRI and DSCT on the one hand, and the narrow B-A interval in the study by Brodoefel et al [19] in which the same post-processing tool was used for both investigations on the other hand, suggesting a possible effect of the post-processing on the results.…”

New Imaging-Based Tools for the Assessment of Ventricular Function in Ischemic Heart Diseases

“…18 The use of DSCT for the determination of ventricular volumes and EF in comparison to CMR showed similarly good results: EDV was underestimated by 3.7 ml, while ESV and EF were overestimated by 2.6 ml and 3.8%, respectively. 19 In another publication by Greupner et al, MDCT was compared with CMR, 2D echocardiography, and 3D echocardiography for the analysis of LV global function after coronary angiography. The study showed comparable limits of agreement for both MDCT and 2D echocardiography in the evaluation of EF vs. CMR.…”