MDCT Derived Left Ventricular Function in Relation to Echocardiography: Validation and Revising the Role with the Evolving Technology

BACKGROUND: Coronary computed tomography angiography (CCTA) is a frequently performed examination for coronary artery disease. When performed with retrospective gating, there is an opportunity to derive functional parameters of left ventricle utilizing automated software. Complementary information, if validated with established standards, will enhance the total value of study. OBJECTIVE: Study evaluates the usefulness of fully automated software for the assessment of left ventricular ejection fraction (LVEF) using 64-slice CCTA data and to correlate CT results with echocardiography (ECHO). Role of CT derived LV function is reviewed in the light of emerging technologies and recent developments in multidetector CT (MDCT). MATERIALS AND METHODS: A total of 113 patients referred for MDCT CCTA for evaluation of coronary artery disease. All patients were scanned on 64 slice GE-Helical CT scanner and had an ECHO done within 1 week of the CT scan. Retrospectively electrocardiogram (ECG)-correlated image reconstruction was performed with the reconstruction at 10% R-R interval increment. Axial image sets were analyzed with advanced workstation using a program-Auto ejection fraction, Circulation: GE Medical Solutions. RESULTS: The mean LVEF calculated by clinical ECHO was 58.6 ± 4.5% and by fully automated software based on CTA data was 58.9 ± 5.4%. The Pearson's regression analysis showed a large correlation, with a correlation coefficient of 0.503 (P < 0.001). Bland-Altman analysis showed a trend towards MDCT resulting in slightly higher values for LVEF when compared with ECHO. CONCLUSION: The fully automated software is simple, reliable, and user-friendly, and can provide rapid assessment of LV functional parameters with good reproducibility. Despite of good correlation, fewer patients are likely to benefit, in future, from this function due to smaller number of patients undergoing CCTA with retrospective gating.