The Evaluation Of Left Ventricular Flow Energy Loss In Patients After Video-assisted Thoracic Lung Resection By Ultrasonic Vector Flow Mapping

Objective:To evaluate the changes on left ventricular structure and cardiac function in patients after video-assisted thoracic lung resection by ultrasonic vector flow mapping,and quantitatively evaluate the diagnostic value of left ventricular flow energy loss for the impaired cardiac function in patients after lung resection.To explore the independent predictors which related to left ventricular flow energy loss.Methods:Thirty-six patients who received lung resection operation in the thoracic department of Sichuan Provincial People’s Hospital,and 30health cases who were came from medical examination center of Sichuan Provincial People’s Hospital in the same period.Routine echocardiographic parameters was measured respectively,and the end diastolic volume of left ventricular（LVEDV）,the end systolic volume of left ventricular（LVESV）,the ejection fraction of left ventricular（LVEF）was acquired by double plane Simpson’s method.The end systolic volume of left atrial（LAVs）,the end diastolic volume of left atrial（LAVd）and the emptying volume of left atrial（LAV-e）was acquired by the area-length method.Aortic flow spectrum and mitral flow spectrum was simutaneously acquired in apical three chamber view,and measured E peak of early diastolic（E）,A peak of late diastolic（A）,E/A ratio,isovolumic relaxation time（IVRT）as well as mitral E wave deceleration time（EDT）.The two dimensional color doppler dynamic map of apical four chamber view,apical three chamber view and apical two chamber view were collected 3 cardiac cycles under the VFM mode,and the raw data was saved to the mobile hard disk.First of all,the dynamic color Doppler imaging of apical three chamber was imported into workstation for VFM analysis,according to the time-flow curve,the early diastolic（ED）was defined to the first peak above the baseline correspond to frame rate,the late diastolic（LD）was defined to the second peak above the baseline correspond to frame rate,and rapid ejection period（REP）was defined to the first valley under the baseline.Drawed the edge of the endocardium in left ventricular cavity,and acquired the parameters related to the left ventricular energy loss,include total energy loss of left ventricular（EL_T）,average energy loss of left ventricular（EL_A）,total energy loss of basal segment in left ventricular(EL_TB),average energy loss of basal segment in left ventricular(EL_AB),total energy loss of middle segment in left ventricular(EL_TM),average energy loss of middle segment in left ventricular(EL_AM),total energy loss of apical segment in left ventricular(EL_TA),average energy loss of apical segment in left ventricular(EL_AA).The same method was used to analyze the apical four chamber view and the apical two chamber view,and the parameters of energy loss were obtained.Finally,the average value of energy loss in left ventricular was calculated by these chambers.General data including Age,SBP,DBP,BMI,LVEDV,LVESV,LVEF,LAVs,LAVd,LAV-e;Diastolic function parameters including E,A,E/A ratio,E/e ratio,EDT and HR;The parameters of left ventricular energy loss which satisfying normal distribution.The differences between groups of all the above parameters were compared by the independent sample t test,and the difference between groups of those left ventricular energy loss which cannot satisfy normal distribution were compared by the Wilcoxon rank sum test.Chi square test was utilized to analyze the difference between groups of counting data.Single-factor regression analysis was used to figure out risk factors like LVEDV,LVESV,LVEF,E,A,HR and hospital stay which can predict left ventricular energy loss.Results:（1）The general data comparison between PCS group and CONTROL group:there was no difference in the age,sex,SBP,DBP,BMI and smoking time between the two groups（p>0.05）.（2）surgical information of PCS group:the resection position including:right upper lobe（RUL）accounted for 27.78%,right middle lobe（RML）accounted for 5.56%,right lower lobe（RLL）accounted for 16.67%,left upper lobe（LUL）accounted for 27.78%,left lower lobe（LLL）accounted for 16.67%.The pathological results of postoperation including 28 cases of non-small cell lung cancer（NSCLC）accounted for PCS group of 77.78%.8 cases of chronic inflammation accounted for PCS group of 22.22%.（3）the comparsion of left ventricular volume and left atrial volume between PCS group and CONTROL group:there was no significant difference in LVEDV,LVESV,LVEF and LVAd between the two groups（p>0.05）,LVAs and LAV-e in PCS group was mild lower than that in CONTROL group（p<0.05）.（4）the comparsion of diastolic function parameters between PCS group and CONTROL group:E,A,E/e and HR in PCS group were significant higher than that in CONTROL group（p<0.05）,EDT,E/A ratio in PCS group were significant lower than that in CONTROL group（p<0.05）,there was no significant differences in the IVRT between two groups（p>0.05）.（5）Comparison of left ventricular energy loss between PCS group and CONTROL group at early diastolic:only EL_TBB and EL_AMM in PCS group has mild difference with CONTROL group（p<0.05）.（6）Comparison of left ventricular energy loss between PCS group and CONTROL group at late diastolic:EL_T,EL_A,EL_TB,EL_TM,EL_AM,EL_AB,EL_AAA in PCS group were significant higher than that in CONTROL group（p<0.05）.（7）Comparison of left ventricular energy loss between PCS group and CONTROL group at rapid ejection period:EL_T,EL_A,EL_AB,EL_AM,EL_AAA in PCS group were significant higher than that in CONTROL group（p<0.05）,EL_TM,EL_TAA in PCS group were significant lower than CONTROL group（p<0.05）.（8）Comparison of the number of vortex around mitral valve between PCS group and CONTROL group at early diastolic:PCS group:none-vortex with24 cases（66.67%）,one-vortex with 3cases（8.3%）,two-vortex with 9 cases（25%）,CONTROL group:none-vortex with 10 cases（66.67%）,one-vortex with 12cases（8.3%）,two-vortex with 8 cases（25%）,there was significant difference between two groups（p<0.05）.（9）Single factor regression analysis of left ventricular energy loss in early diastolic,late diastolic and rapid ejection period in PCS group:left ventricular energy loss（EL_T）of early diastolic was positively correlated with E peak,and was significantly negatively correlated with hospital stay（p<0.05）.Left ventricular energy loss（EL_T）of late diastolic was positively correlated with E peak and A peak（p<0.05）.Left ventricular energy loss（EL_T）of rapid ejection period was significantly negatively correlated with hospital stay（p<0.05）.Conclusion:（1）Although left ventricular ejection fraction was still within the normal range,but changes of left ventricular morphology,structural parameters and left ventricular relaxation were occured in the early stage after lung resection.（2）The fluid characteristics of the left ventricular cavity were changed in the early stage after lung resection:the vortex ring under the anterior leaflet of mitral valve disappeared or just one or more small vortex rings under posterior leaflet of the mitral valve.There was higher and wider distribution of left ventricular energy loss at Early diastolic,late diastolic and rapid ejection period.（3）The left ventricular energy loss at early diastolic phase and rapid ejection period was significantly higher than that in the control group.（4）Compared with the ejection fraction of left ventricular,the left ventricular energy loss can reflect the change of left ventricular systolic function more earlier and sensitiver.（5）Left ventricular energy loss at early diastolic can be independently predicted by E peak of the mitral valve,and left ventricular energy loss decreases with the extension of hospital stay.Left ventricular energy loss at late diastolic can be independently predicted by the flow velocity of mitral valve,particulary moderate corrrlated with A peak of late diastolic.There was a significant negative correlation between the left ventricular energy loss at rapid ejection period and the duration of hospitalization.More faster in mitral valve inflow velocity,more greater left ventricular energy loss.