Study of left ventricular morphology and function in patients with hypertensive disorder complicating pregnancy by echocardiography and their correlation with N-terminal probrain natriuretic peptide

Objective To assess the changes of left ventricular morphology and function in patients with hypertensive disorder complicating pregnancy and their correlation with the N-terminal brain natriuretic peptide precursor (NT-proBNP) by echocardiography, as well as to investigate the clinical value of the ratio of mitral valve diastolic early E wave peak velocity and early diastolic myocardial motion peak velocity in the mitral annulus (E/Ea), systolic myocardial motion peak velocity in the mitral annulus (Sa) in evaluating early left ventricular dysfunction. Methods One hundred and forty parturients admitted to Shaoxing Women & Children’s Hospital from October 2013 to March 2016 were enrolled in this study. The observation group (89 cases) was divided into three subgroups: pregnancy induced hypertension group (25 cases), mild preeclampsia group (28 cases) and severe preeclampsia group (36 cases). Fifty-one cases of normotensive parturients were enrolled in the control group. The parameters of left ventricular structure were measured by echocardiography, including interventricular septal thickness at end diastole (IVSd), left ventricular diameter at end diastole (LVDd), left ventricular posterior wall thickness at end diastole (LVPWd), relative wall thickness (RWT) and left ventricular mass index (LVMI); the parameters of left ventricular function were also measured by echocardiography, including left ventricular ejection fraction (LVEF), E/A, systolic myocardial motion peak velocity of left ventrical lateral wall and ventricular septum in the mitral annulus (Sa1 and Sa2), early diastolic myocardial motion peak velocity of left ventrical lateral wall and ventricular septum in the mitral annulus (Ea1 and Ea2). E/Ea1, E/Ea2 were calculated. Meanwhile, plasma NT-proBNP concentrations of each group were detected. The method of Pearson correlation analysis investigated the correlation of NT-proBNP. Results Compared with the control group, the parameters of left ventricular morphology in the severe preeclampsia group increased significantly, including IVSd [(0.79 ± 0.09) cm vs. (0.91 ± 0.12) cm], LVDd [(4.61 ± 0.38) cm vs. (4.84 ± 0.27) cm], LVPWd [(0.80 ± 0.10) cm vs. (0.90 ± 0.15) cm], RWT [(0.35 ± 0.04) vs. (0.38 ± 0.05)] and LVMI [(58 ± 8) g/m2 vs. (72 ± 13) g/m2] (all P < 0.05); In the mild preeclampsia group, Sa1 [(10.7 ± 2.3) cm/s vs. (9.7 ± 1.9) cm/s] and Sa2 [(9.2 ± 1.6) cm/s vs. (8.4 ± 1.5) cm/s] decreased, E/Ea1[(6.5 ± 1.9) vs. (7.8 ± 2.6)] and E/Ea2 [(8.3 ± 2.1) vs. (9.6 ± 2.5)] increased (all P < 0.05); In the severe preeclampsia group, Sa1 [(10.7 ± 2.3) cm/s vs. (9.4 ± 1.7) cm/s] and Sa2 [(9.2 ± 1.6) cm/s vs. (8.2 ± 1.4) cm/s] significantly decreased, E/Ea2 [(6.5 ± 1.9) vs. (8.0 ± 2.6)] and E/Ea1 [(8.3 ± 2.1) vs. (10.6 ± 2.4)] significantly increased (all P < 0.05), E/A decreased [(1.30 ± 0.26) vs. (1.15 ± 0.29)] (P < 0.05). Pearson correlation analysis showed plasma NT-proBNP was positively correlated with E/Ea1 and E/Ea2 (r = 0.58, 0.42; all P < 0.05); NT-proBNP was negatively correlated with Sa1 and Sa2 (r = -0.69, -0.30; all P < 0.05). Conclusions Hypertensive disorder complicating pregnancy can lead to the changes of left ventricular morphology and function. In addition, left ventricular function can be changed ahead of left ventricular morphology. Measurement of E/Ea and Sa by using echocardiography showed a good correlation with NT-proBNP, which can be used as the early indicators to evaluate left ventricular function of patients with hypertensive disorder complicating pregnancy. Key words: Echocardiography; Tissue Doppler; N-terminal brain natriuretic peptide precursor; Ventricular function, left; Hypertensive disorder complicating pregnancy