Assessment Of Left Ventricular Systolic Function By Longitudinal Layer-specific Strain Before And After PCI In Patients With Coronary Heart Disease

Objective:To analyze longitudinal strain in endo-myocardium,mid-myocardium,epi-myocardium of left ventricle(LV)by myocardial stratified strain technique before and after percutaneous coronary intervention(PCI)in patients with coronary heart disease(CHD),and to provide the basis for treatment.Methods:According to the results of selective coronary arteriography,A number of 56 selected patients were divided into two groups: single branch group(26 cases)and multi-branch group(30 cases),30 healthy volunteers were selected as the control group.Left ventricular end-diastolic diameter(LVEDD)and Left ventricular end-systolic diameter(LVESD)were measured by conventional echocardiography.Left ventricular end-diastolic volume(LVEDV),left ventricular end-systolic volume(LVESV)and Left ventricular ejection fraction(LVEF)were measured by Simpson method.GE Echo PAC software was used to obtain territorial and global longitudinal strain of endo-myocardium,mid-myocardium,epi-myocardium.The transmural gradient of longitudinal layer-specific strain was calculated.Compare of the changes of longitudinal layer-specific strain parameters and the degree of improvement before and after PCI.Results:1.Both control and CHD groups before and after PCI,GLSendo,GLSmid,GLSepi,TLSendo,TLSmid and TLSepi showed a gradient decrease(P<0.05).2.Compared with the control group,LVEDV and LVESV were significantly increased in the multi-branch group,while LVEF and longitudinal layer-specific strain parameters in the single branch and multi-branch groups were decreased before PCI(P<0.05).3.Compared with one week after PCI and before PCI,there was no significantly difference for the conventional parameters and longitudinal layer-specific strain parameters in CHD group(P>0.05).4.In CHD group,LVEF increased after 3 months of PCI and gradually increased with time(P<0.05),but was still lower than control group in 6 months later(P<0.05).5.In single branch group,TLSendo,TLSmid,TLSepi,GLSendo,GLSmid,and GLSepi increased after 1 month of PCI and continually increased along with the time.The longitudinal layer-specific strain parameters were partially recovered to normal level in 3 months later(P>0.05).△TLSendo-epi,△TLSendo-mid,△TLSmid-epi,△GLSendo-epi,△GLSendo-mid,△GLSmid-epi ncreased after 3 months of PCI and gradually increased with time,and reached the normal level after 3 months(P>0.05).6.In the multi-branch group,TLSendo,TLSmid and TLSepi increased after 1 month of PCI,while GLSendo,GLSmid and GLSepi increased,and gradually increased with time.6 months after PCI,but all of them were lower than the control group in 6 months later(P<0.05).△TLSendo-epi,△TLSendo-mid and △TLSmid-epi increased after 6 month of PCI(P<0.05).There was no significantly difference for △GLSendo-epi,△GLSendo-mid and △GLSmid-epi between before and after PCI(P>0.05).7.LVESV,LVEF,GLSendo,GLSmid and GLSepi were significantly lower in the multi-branch group than those in the single branch group before and after PCI(P<0.05).TLSendo,TLSmid,TLSepi,△GLSendo-epi,△GLSendo-mid and △GLSmid-epi were lower in the multi-branch group than those in the single branch group after 1,3 and 6 months of PCI(P<0.05).There were no significant difference for △TLSendo-epi,△GLSendo-mid and △TLSmid-epi between the two groups before and after PCI(P>0.05).8.The territorial longitudinal layer-specific strain is better than the global longitudinal layer-specific strain in the degree of improvement after PCI.The degree of improvement in endo-myocardium,mid-myocardium,epi-myocardium showed a gradient decrease.The single branch group is better than the multi-branch group in the degree of improvement after PCI.There were no statistical difference in the above rules(P>0.05).The degree of improvement in the two groups gradually increased with time after PCI(P<0.05).Conclusion:1.The systolic function of left ventricular before PCI in patients with CHD was significantly decreased compared with the normal control group.The systolic function of left ventricular after PCI have been significantly improved,and gradually increased with time.2.The regional systolic function of left ventricular improved earlier than the global systolic function in the multi-branch group.3.The systolic function of left ventricular in the single branch group after PCI improved and recovered to normal level earlier than the multi-branch group.4.The longitudinal layer-specific strain is earlier than the longitudinal transmural gradient of myocardial wall to evaluate the efficacy of PCI.