Global left ventricular function: assessment with dual-source CT versus conventional ventriculography in a porcine model

Objective —Cardiac computed tomography (CT) and conventional biplane ventriculography are established methods for the determination of ventricular function. Recently dual source CT was introduced for cardiac CT scanning providing a temporal resolution of 83ms independent of the patient’s heart rate.The purpose of this study was to assess the global left ventricular function using retrospectively ECG-gated dual source computed tomography (DSCT) in comparison to conventional ventriculography.Methods and results —Contrast-enhanced cardiac DSCT and conventional ventriculography were performed in 10 domestic pigs with an approximate weight of 60kg using standardized examination protocols under general anaesthesia. From manually drawn endocardial contours, LV end-systolic (ESV) and end-diastolic volume (EDV), stroke volume (SV), ejection fraction (EF) were calculated by means of dedicated analysis software separately for both examination modalities. LV functional parameters were analysed using Bland-Altman plots, Student t-test, and Pearson correlation coefficient. Left ESV and EDV determined with DSCT correlated well with conventional ventriculography results (ESV: r=0.86; EDV: r=0.72) with a good correlation also for SV (r=0.67).An only moderate correlation was found for EF (r=0.52). Student t-test showed a significant underestimation of SV and EF derived from DSCT in comparison to ventriculography.Conclusion —Retrospectively ECG-gated DSCT can accurately determine LV volumes in comparison to conventional ventriculography but provides lower SV and EF values; however, the correlation was only moderate.