The Study On The Relationship Of The Left Ventricular Filling Pressure And Left Ventricular Filling Pattern In Patients With Acute Myocardial Infarction

Objective:To explore the relationship of left ventricular filling pressure and left ventricular filling pattern by using cardiac catheterization and echocardiography,and to search the main influence factor of left ventricular filling pressure.Methods:1 Forty patients with AMI aged 31-78 were enrolled as the experimental group,including 28 males and 12 females,mean age of( 57.8 + 11.12).AMI diagnostic criteria was as follows accord with the standards established by the Chinese Cardiovascular disease society in 2001[10]:(1) the typical clinical symptoms of ischemic chest pain;(2) the ECG had characteristic graphics of dynamic evolution;(3) c Tn T or myocardial enzymes elevated.All patients must have more than two of the above criteria or two before being selected.We selected 10 healthy subjects who were matched age and gender with the AMI patients to serve as controls.2 A set of color Doppler ultrasonic system(GEVIVID7) was used,the probe frequency is 2.0 ~ 5.0MHZ.Transthoracic echocardiography was performed in all patients within 24-48 hours after admission to hospital.All subjects had left lateral position,kept a quiet breathe and were connected to chest lead ECG.All the data were recorded in 3 continuous cardiac cycle and were stored in hardware for analysis.Left ventricular filling pattern indexes:get the apical four chamber view:with the pulse Doppler samp volume at mitral tip,we can get mitral valve flow spectrum, recording of mitral valve flow spectrum, detection of mitral early diastolic peak flow velocity(E),late peak velocity(A),E wave deceleration time(EDT),left ventricular isovolumic relaxation time(IVRT), and the ratio of E/A. with the pulse Doppler samp volume at mitral tip.Tissue doppler imaging:enter TDI mode:with the samp volume at mitral annulus,we can measure the mitral annular early diastolic average value of the side wall and the partition of the maximal velocity(Ea), and the ratio of E/Ea.Color M mode Doppler echocardiography:Get the apical four chamber view,M mode sampling line was adjusted from the apex to the mitral valve, and then to the left atrium,which is parallel to the blood direction in the early diastolic.and the left ventricular inflow tract color flow mapping E wave were recorded,the velocity reversal of E wave at the first time is the slope of flow propagation velocity(Vp).Determination of left ventricular volume:apical four chamber view,start the 3D mode,the storage of a left ventricular volume image,measured left ventricular ejection fraction(LVEF).3 Cardiac catheterization was performed within 24 hours after the last time echocardiography.After percutaneous right femoral artery intubation,6F pigtail catheter was implanted in the left ventricle,measuring left ventricular end diastolic pressure(LVEDP).Results: 1 Comparison of left ventricular function between acute myocardial infarction and the control group 1.1Comparison of basic dataCompared with the control group,acute myocardial infarction,have no significant difference in age,gender,heart rate(Table 1). 1.2 Comparison of ultrasound index parametersCompared with the control group,patients with acute myocardial infarction was found: EDT,LAD,IVRT,E/Ea,E/Vp were increased,P<0.01 had statistical significance;E,Vp,Ea were decreased,P<0.01 had statistical significance; however,two groups of LVEF,A,E/A had no significant difference(P>0.05)(Table 2). 2 Analysis of the left ventricular function parameters of different filling pattern in patients with acute myocardial infarction 2.1 Division of the different diastolic filling patternThe left ventricular filling patterns of 40 patients with reference to the literature[11]is divided into:normal filling group 10 cases,impaired relaxation group13 cases, pseudo-normal group 9 cases, restrictive filling Group 8 cases. 2.2 Comparison of general clinical dataCompared with normal filling,the age increased in impaired relaxation group, pseudo-normal group and restrictive filling group(P<0.05), the heart rate increased in pseudo-normal group and restrictive filling group also significantly(P<0.05). 2.3 The results of echocardiography parameters and left ventricular filling pressure in different left ventricular filling patternCompared with normal filling, in impaired relaxation group,E,E/A,EDT, Vp and Ea decreased,A,LAD,IVRT,E/Ea,E/Vp and LVEDP increased;in pseu- donormal group, EDT, Vp and Ea decreased, LAD,IVRT,E/Ea,E/Vp and LVE- DP increased;in restrictive filling group A,EDT,Vp and Ea time to reduce, E, E/A, LAD,E/Ea,LVEDP and E/Vp increase. 3 Correlation analysis 3.1 Correlation of left ventricular filling pressure and left ventricular structural parametersMitral early diastolic peak flow velocity of E,A,E/A,IVRT and LVEDP have no obvious correlation(R=0.23,R=-0.296,R=0.261,R=-0.259), and therefore can not well reflect the level of LVEDP.EDT and LVEDP have strong negative correlation(R=-0.83),The regression equation shows that, when the increase in EDT per 1ms, LVEDP can reduce 0.66 mm Hg(Table 4), in impaired relaxation group pseudo-normal group and restrictive filling group, it is also very strong(R=-0.80,R=-0.87,R=-0.73),so in the different filling mode,the EDT can reflect the level of LVEDP;LAD and LVEDP have A low to moderate positive correlation(R=0.52),the regression equation shows that, when the increase in LAD per 1cm,LVEDP increased 10.234 mm Hg(Table 4),but in the impaired relaxation group there had no obvious correlation( R=0.15),so the LAD is a better index for predicting severe diastolic dysfunction; E/Ea and LVEDP showed a strong positive correlation( R=0.92), the regression equation shows that, when the E/Ea increased by 1,LVEDP increased 1.67 mm Hg(Table 4),and in the different filling mode impaired relaxation group, pseudo-normal group,restrictive filling group also showed a strong positive correlation( R=0.92, R=0.98, R=0.95),so the E/Ea can be used to estimate LVEDP; E/Vp and LVEDP showed a strong positive correlation(R=0.91),the regression equation shows that, when the E/Vp increased by 1, LVEDP increased 4.205 mm Hg(Table 4),and in the different filling mode impaired relaxation group, pseudonormal group,restrictive filling group also showed a strong positive correlation(R=0.91,R=0.938,R=0.95), many research discovery,E/Vp in reflecting left ventricular filling pressure is a very good indicator. 3.2 Correlation of left ventricular filling pressure and left ventricular filling patternAccording to the analysis of Spearman rank correlation, the correlation between Left ventricular filling pressure and left ventricular filling pattern( R=0.89), Left ventricular filling pressure increased with the severity of left ventricular diastolic function abnormality.Conclusions:1 the filling pressure and left ventricular filling patterns showed a highly positive correlation.Left ventricular filling pressure were rising with the change of left ventricular filling patterns from abnormal relaxation to restrictive filling.2 EDT and E/Ea showed a positive correlation, which can reflect the left ventricular filling pressure.3 left atrial size and left ventricular filling pressure showed a moderate positive correlation, which can reflect the left ventricular filling pressure.4 E/Vp and left ventricular filling pressure were highly related, which can reflect the left ventricular filling pressure.