Objective To evaluate left intra-ventricular diastolic blood flow patterns and fluid dynamics in pre diabetics using vector flow mapping(VFM),and to explore the value of left intra-ventricular hydromechanics characteristics assessment of intracardiac flow by VFM with more sensitive indexes.Methods Forty four patients with type 2 diabetes,twenty-eight pre-diabetes patients and thirty-three normal volunteers underwent VFM to determine the left ventricular(LV) diastolic blood flow patterns and fluid dynamics.The two-dimensional color Doppler flow images data were acquired in standerd apical fourchamber view during 3 complete cardiac cycles.These images were analyzed using a dedicated off-line workstation.At different level (mitral annulus,papillary muscl and apex level),the diastole blood flow parameters of LV including flow velocity and volume,velocity gradients (△V),pressure gradients (△P),diastole flow volume,vortex intensity ( Ⅵ),vortex area ( VA),vortex radius (VA) were derived.Thedifferences of the above parameters were compared among the three groups.The correlationship between diastolic function parameters and LV hydromechanics indexes were analyzed.Results ① Compared to normal group and pre-diabetics group,the LV diastolic function parameters E/A and e/a in diabetics group were lower( P ＜0.01),with no differences for E/e( P ＞0.05).There were no significant diffrences of these indices between diabetics group and pre-diabetics group( P ＞0.05).②)Compared to normal group,the intraventricular peak flow velocity at basal level,△V and △P in diabetics group and pre-diabetics group were lower( P ＜0.01),but there were no significant differences of these indices between diabetics group and prediabetics group( P ＞ 0.05).③Compared to normal group,the diastolic positive volume at basal level in diabetics group and pre-diabetics group was lower ( P ＜0.01 ),but there was no significant differences of these indices between diabetics group and pre-diabetics group ( P ＞ 0.05).④ Compared to the normal group,the Ⅵ in diabetics and pre-diabetics group was decreased,but there were no significant differences of these indices between diabetics group and pre-diabetics group( P ＞0.05).The VA and VR in diabetics and pre-diabetics group were increased,but there were no significant differences of these indices between diabetics group and pre-diabetics group ( P ＞ 0.05).⑤ There were no correlationship between diastolic function parameters and LV hydromechanics indexes.Conclusions There is the same LV diastolic blood flow patterns and fluid dynamics existed in pre-diabetics as diabetics.VFM could be used as a new methods to demonstrate the early left intra-ventricular fluid dynamics damages in pre-diabetics patients.