Assessment Of Left Ventricular Flow Vector In Patients With Acute Anterior Myocardial Infarction After PCI By Vector Flow Mapping

Aim:1 To quantitative estimate the structure of left ventricle by vector flow mapping and the peak stain with stain tracking imaging in healthy volunteer,and explore the correlation between the blood flow structure with flow dynamics. 2 To quantitative evaluate the function of left ventricle through flow vector during contraction period in patients with acute anterior myocardial infarction after percutaneous coronary intervention by vector flow mapping.Methods:1 Subjects:Thirty healthy volunteers were identified as controls. Twenty-five patients with acute anterior myocardial infarction were involved and followed-up in the study. 2 Equipments:Using Aloka ɑ10 ultrasonic diagnosis system with DSA-RS1 work station and GE Vivid7 Demision ultrasound system with Echo PAC data analysis software. 3 Measurement: To measure the maximal vector velocity at the level of basic, middle and apex of the LV.And then compare the maximal vectorvelocity at each level of the LV in patients before PCI with those after PCI and controls.Correlation analysis was made between Vmax and LVEF.The peak strain of controls was obtained in base level,middle level and apex level.Correlation analysis was made between Vmax and peak strain.Results:1 The Vmax gradually increased from apex to base in the control group(P<0.05). 2 The strain gradually decreased from apex to base in the control group(P<0.05).The Vmax was negative correlation with strain in base level( r=-0.366,P<0.05),and uncorrelated in middle level( r=-0.05,P>0.05),and positive correlation in apex level(r=0.513,P<0.05). 3 Compared with the control group, the Vmax of three level of LV were lower before PCI(P<0.05),and they have no significant change after three days(P>0.05).One month later, the velocities significantly increased, when compared with those before PCI(P<0.05). The Vmax of control group was positive correlation with LVEF(r=0.419~0.780,P<0.05).In the patient group,the Vmax at the level of middle and apex were positive correlation with LVEF(r=0.497,P<0.05;r=0.510,P<0.05),the Vmax of basic was uncorrelated with LVEF(r=-0.126,P>0.05).Conclusions:1 There are the tendency that the Vmax gradually increased from apex to base in left ventricle of healthy volunteer.The hemodynamics strongly linked with myocardiol function.2 The Vmax of patients was significantly increased after one month.VFM is more sensitive than LVEF in accessing the function of LV.VFM may serve as a new tool to evaluate the effect of PCI.