Study On Assessment Of Left Ventricular Function With Quantitative Tissue Velocity Imaging (QTVI) Echocardiography And Determination Plasma B-type Natriuretic Peptide (BNP) In Heart Failure Patients

Study on assessment of left ventricular function with quantitative tissue velocity imaging (QTVI) echocardiography and determination plasma B-type Natriuretic Peptide (BNP) in heart failure patients.OBJECTIVETo analysis the correlation between the mean peak velocities of mitral annulus during systole, early and late diastole ( Sm,Em,Am) and mean systolic displacement of mitral annulus (Dm) that were determined by quantitative tissue velocity imaging (QTVI), concentration of B-type Natriuretic Peptide (BNP) and functional parameter of the left ventricle determined by conventional echocardiography in heart failure patients before and after treatment. To evaluate the clinical value of QTVI and BNP in assessment the left ventricular systolic and diastolic function in heart failure patients.METHODSAll the patients and controls were determined left atrium(LA), Left ventricular end-diastole dimension (LVEDD),Left ventricular end-systole dimension (LVESD) by conventional echocardiography ,and left ventricular ejection fraction (LVEF) by Simpson's rule. Transmitral flow velocity during early diastole (E) and late diastole (A) were also measured by pulse-wave Doppler echocardiography and E/A ratio was calculated. The velocities of mitral annulus during systole, early and late diastole (Sm,Em,Am ) and systolic displacement (Dm)of mitral annulus from posteroseptal,lateral,anteroseptal,posterior,anterior and inferior segments were determined by quantitative tissue velocity imaging (QTVI),than the Ern/Am was calculated. Concentration of plasma B-type Natriuretic Peptide (BNP) were detected immediately. After treatment 3-4 weeks, all of the patients were determined again.RESULT(1) Mean Sm and Dm had positive correlation with LVEF(r=0.87 and r=0.89, p＜0.01). Area under the ROC curve was 0.99 for mean Sm that forecasted LVEF＜50%. Mean Sm＜5.15cm/s was used as a cut-off point for the prognostic test, the sensitivity was 97.83%, specificity was 94.29%, accuracy rating was 96.30%. Area under the ROC curve was 0.99 for mean Dm that forecasted LVEF＜50%. Mean Dm＜8.49mm was used as a cut-off point for the prognostic test, the sensitivity was 91.30%, specificity was 94.29%, accuracy rating was 93.83%.(2) Compared with the normal group,mean Em in all 3 subgroups of diastolic dysfunction in the CHF groups significantly decreased(p＜0.01), mean Em decreased gradually along with diastolic dysfunction aggravated.(3) The concentration of BNP in the CHF group was obviously higher than those in the normal group (P＜0.01). The concentration of BNP in the CHF patients after treatment was obviously lower than those before treatment(P＜0.01). Concentration of BNP had negative correlation with LVEF (r=-0.85,P＜0.01). Area under the ROC curve was 0.99 for BNP that forecasted LVEF＜50%. BNP＞96.35ng/L was used as a cut-off point for the prognostic test, the sensitivity was 90.70%, specificity was 100.00%, accuracy rating was 93.10%.CONCLUSIONThe mean systolic velocity of mitral annulus (Sm),mean systolic displacement of mitral annulus (Dm) determined by quantitative tissue velocity imaging (QTVI) and concentration of B-type Natriuretic Peptide (BNP) can reflect the left ventricular systolic function ;and the mean early diastolic velocity(Em) can evaluate the left ventricular diastolic function. If the two examinations are combined, they will provide more affluent and precise parameters for assessment of heart dysfunction.