To evaluate ventricular function in fetuses with ventricular hypoplasia by atrial-ventricular annular displacement (AVAD).

(1) A total of 150 normal fetuses at gestational age 19~41 weeks were selected as control group in this study. M-mode echocardiography was used to measure AVAD, the left ventricular ejection fraction (LVEF), and left ventricular fractional shortening (LVFS). The two-dimensional ultrasound trace method was used to measure the right ventricular end-diastolic area (RVEDA) and right ventricular end-systolic area (RVESA), And the right ventricular percent change in area (RVPCA) was calculated. Pulsed wave (PW) Doppler was used to measure the E and A peak flow rate, and the atrioventricular mitral valve flow velocity curve was drawn. Tissue Doppler imaging (TDI) was used to measure Em, Am and Sm, respectively, and the atrioventricular prosthetic ring flow rate curve was drawn. A quantitative analysis was conducted to determine the correlation between AVAD and gestational age and conventional ventricular function parameters. (2) A total of 49 fetuses with ventricular dysplasia were selected as study group, including 23 fetuses with left ventricular dysplasia (HLHS) and 26 fetuses with right ventricular dysplasia (HRH). For them, AVAD was measured by M-type echocardiography. A comparative study of these fetuses was conducted with 30 fetuses in the control group.

(1) In control group AVAD increased with gestational age (GA); E and A were positively correlated with Em, Am and Sm (P<0.01); mitral annular displacement (MAD) was positively correlated with E, A, Em, Am and Sm (r=0.347, 0.290, 0.407, 0.393, 0.517, all P<0.01); tricuspid annular displacement (TAD) was positively correlated with E, A, Em, Am and Sm (r=0.351, 0.320, 0.497, 0.403, 0.598, all P<0.01); MAD was not correlated with LVEF and LVFS (r=0.199, 0.258, both P>0.05); while TAD was positively correlated with RVPCA (r=0.837, P<0.01). (2) Compared with that of the control group, fetal MAD with HLHS was lower [(7.11±0.56) mm vs (7.80±0.87) mm], and TAD was higher [(9.78±2.11) mm vs (9.38±1.51) mm], all these differences were significant between study and control groups (t=2.98, 2.47, both P<0.05). Meanwhile, the fetal MAD with HRH was higher than that of the control group [(8.35±0.69) mm vs (7.80±0.87) mm], and TAD was lower [(7.98±1.69) mm vs (9.38±1.51) mm]. Aall these differences were significant between study and control groups (t=2.42, 4.18, both P<0.05).

AVAD is a valuable parameter to evaluate the long axis function of fetal heart in fetuses with ventricular hypoplasia, which can provide valuable information about the circulation characteristics in prenatal consultation.