Evaluation Of Left Ventricular Function In Patients With Uremia By Echocardiographic Speckle Tracking Of Mitral Annular Displacement

ObjectiveUremic myocardiopathy is a major complications of the end of chronic renal insufficiency. For metabolic toxins, anemia, heart aggravated comprehensive role before and after load caused myocardial vasomotion dysfunction. Its main pathological change is myocardial interstitial fibrosis. Echocardiography has important effect when used to evaluate the heart of uremic patients, better than the electrocardiogram, X-ray, and clinical comprehensive evaluation. Left ventricular ejection fraction is widely accepted and used clinically evaluation index of left ventricular systolic function. But in some pathological conditions, such as the left ventricular wall thickening or left ventricular expanding, it will affect its accuracy of evaluation left ventricular systolic function. And recent studies show that for patients with chronic cardiac failure, the correlation between LVEF measured by ultrasound and brain natriuretic peptide (BNP) in plasma is poor, the same to classification scheme cardiac function proposed by New York Heart Association. So looking for simple, accurate method to evaluate left ventricular systolic function has been a direction for ultrasound workers. Research has proved that the correlation between mitral annulus systolic movement and left ventricular systolic function is good. M type ultrasonic and Tissue Doppler ways to measure the mitral annulus movement were mainly adopted in the past. There are certain angle-dependent, and they are more time-consuming, effortless. Speckle tracking imaging technology can follow the movement of mitral annulus and measure displacement and speed in all the cardiac cycle of mitral annulus relative to apex, thereby can be used to evaluate left ventricular overall systolic and diastolic function. This study is to observe the value of speckle tracking of mitral annular displacement method in the assessment of left ventricular systolic function in patients with uremia.Methods30 cases patients of uremia in our hospital during the period of February 2010-June 2010. This group includes 16 men and 14 women, aging from 22 to 67 and averaging 40.84±9.40 years old. The control group includes 30 health,17 men and 13 women, aging from 20 to 66and averaging 42.51±8.74 years old.Without coronary heart disease, high blood pressure, diabetes and kidney disease etc. The results examined by ECG and UCG were no abnormalities, the age,sex and heart rate matched with the uremia group. Applied PHILIPS IE33 color Doppler ultrasound diagnostic instrument. Each heart chamber size and the thickness of left ventricular wall measured by conventional echocardiography. Simplify the bi-planar Simpson method for measuring the left ventricular ejection fraction (LVEF). Then images of four-chamber, two-chamber and three-chamber apical views were stored at the same time. Take three successive stable cardiac cycle. STI parameters included:①The maximal displacement of the six points of mitral annulus (Ds),②the time to peak systolic displacement(T),③percent of standardized displacement from the middle of the mitral annulus to apex(Dm%).The data were measured three times, and take their average. The correlations between Ds and LVEF, Dm% and LVEF were analyzed, and LVEF was calculated by Simpson method.Results1. Control group and uremia group comparison of clinical information and common indicators measured by UCG There were no differences in age weight, heart rate between two groups. In patients with uremia, creatinine and blood pressure increased, the hemoglobin decreased, LADs,LVDd increased, IVSd,LVPWd thickened, E/A,LVEF,FS decreased, the differences were statistically significant.2. Control group and uremia group comparison of the indicators of mitral annulus motion in systolic period Compared with control group, the six points of mitral annulus displacement, the mean of Ds and Dm% decreased, the time to peak systolic displacement increased, the differences were statistically significant.3. The correlations between Ds and LVEF, Dm% and LVEF were analyzed, both Ds and Dm% correlated well with LVEF in two groups, but the correlation coefficient in control group was higher, and the correlation coefficient of Dm% was higher than Ds.Conclusion1. Compared with control group in various common indicators, the blood pressure increased and the hemoglobin decreased in patients with uremia, the damage of Uremic myocardioPathy was obvious both in form and function. LADs,LVDd increased, the parameters which reflect left ventricular systolic and diastolic function, such as ejection fraction(EF),short—axis fractional shortening(FS) and flow E/A ratio at mitral valve opening decreased.2. Compared with control group in STI indicators, both Ds and Dm% decreased, the time to peak systolic displacement increased in patients with uremia, the differences were statistically significant. It means the systolic function of left ventricular in patients with uremia decreased.3. Both Ds and Dm% correlated with LVEF in two groups, but the correlation in control group was better, and the correlation of Dm% was better than Ds. So, Ds and Dm% can also be used to reflect the systolic function of left ventricular. Mitral annulus displacement measured by STI had its unique value when used to evaluate the systolic function of left ventricular in patients with uremia.