Comparison Of Brain Natriuretic Peptide And Left Ventricular Function Determined By Tissue Velocity Imaging In Patients With Essential Hypertension

Objective To evaluate global left ventricular function in patients with essential hypertension by Tissue Velocity Imaging (TVI) and to compare with plasma BNP concentration.Methods 139 patients with essential hypertension were divided into LVH group(n=61) and N-LVH group(n=78) based on left ventricular mass index (LVMI). 76 health adults were selected as contral group. Interventricular septum thickness (IVSd),Left ventricular posterior wall thickness (LVPWd),Left ventricular internal dimensions (LVIDd) in end diastole were measured by M-mode echocardiography. Left ventricular eject faction(EF) was assessed by improved Simpson formular.Conventional left ventricular diastolic function parameters were acquired by pulsed Doppler. The mitral annular peak systolic (S_m) and early diastolic (E_m) and peak late (Aa) velocities were determined by TVI. Plasma BNP levels were measured by ELISA. The function parameters of the LVH group and N-LVH group were compared with the normal group, and the corrections between the parameters were analyzed.Results M-S_m,M-E_m,M-E_m/M-Aa were reduced in hypertensive subjects with LVH and without LVH compared with contral group,while LVMI,LVIDd,RWT,A_m,E/M-E_m,Plasma BNP concentration were increased .LVMI correlated positively with E/M-Ea and correlated negatively with M-Sm and M-Em. M-S_m correlated positively with M-E_m. E/M-E_m correlated negatively with M-S_m and M-E_m and M-E_m/M-A_m. Plasma BNP concentration correlated positively with LVMI and LVIDd and negatively with M-Em and M-E_m/M-A_m and EF.The area under the receiver-operating characteristic curve(AUC) for M-E_m to detect any diastolic dysfunction was 0.865. The AUC for Plasma BNP concentration to detect left ventricular hypertrophy was 0.851. The AUC for Plasma BNP concentration to detect moderate and serious diastolic dysfunction was 0.903. ROC curves were built to search for reliable parameters to detect diastolic dysfunfonction,disriminate pseudonormal and detect left ventricular hypertrophy.Conclusions (1)Reductions in mitral annulus systolic and diastolic velocities parallel increases in LV mass in hypertensive subjects, beginning at LV mass within the clinically defined normal values. (2)Systolic function is impaired in hypertensive subjects with normal ejection fraction. (3)TVI and plasma BNP concentration provid new effective methods to quantitatively assess the cardiac function.(4) Plasma BNP concentration can be used to detect left ventricular hypertrophy.