Objective To investigate the short axis systolic function of children with single-left ventricle(LV),and to appraise the clinical value of velocity vector imaging(VVI) on assessing it.Methods The study group consisted of 14 patients with single-LV.The control group consisited of 14 age-matched normal children.VVI was used to analyse the circumferential and radial strain and strain rate of regional single-LV at the level of papillary muscle.Results Compared with values in control group,single-LV circumferential strain values were significantly lower in anterior septum,posterior septum,anterior wall,lateral wall and inferior wall(all P ＜0.05).Single-LV circumferential strain rate values were significantly lower in anterior septum,posterior septum,anterior wall,lateral wall and posterior wall compared with controls(all P ＜0.05). In control group,circumferential strain and strain rate were higher in inferior septum and anterior septum compared with other segments( P ＜0.05).Single-LV radial strain values were significantly lower in all segments compared with values in control (P ＜ 0.05).In control group,radial strain and strain rate of papillary muscle level showed no significantly difference( P ＞0.05).Conclusions Circumferential and radial systolic ventricular function are impaired in children with single-LV.VVI can beused as a quantitative tool in evaluating the short axis systolic function of single-LV.