RESUMO
Objective To investigate the value of synchronous recording of Doppler blood flow spectrum of fetal pulmonary artery and vein in quantitative measurement of fetal heart conduction time. Methods A total of 221 fetuses aged 16-41 weeks were enrolled in this study.Each fetus was measured by pulsed Doppler (PD),tissue Doppler (DTI) and pulmonary arteriovenous synchrony (PA-PV). Atrioventricular conduction time (AV) and the time period from ventricular contraction began to shrink to the next cardiac atrial contractions (VA) were recorded for comparing the consistency of three measure methods.Results ①The AV and VA obtained by three different measurement methods have no significant difference after any comparison( P >0.05). ②There was a significant positive correlation between AV and gestational age (r= 0.825, P = 0.000). There was a weak correlation between VA and gestational age (r=0.216,P =0.000). ③AV was negatively related to heart rate ( r = -0.236,P =0.000);VA was negatively related to heart rate( r = -0.860,P =0.000). ④There was a positive correlation between AV and biparietal diameter ( r = 0.188, P = 0.005). There was no significant correlation between VA and biparietal diameter ( r = 0.054, P = 0.428). ⑤ AV and VA in different gestational weeks fetuses were analyzed by ANOVA. The differences in AV among PD,DTI and PA-PV groups were statistically significant ( P =0.014),AV > 36 weeks was the longest,and there was no significant difference in VA among PD,DTI and PA-PV groups ( P =0.941). ⑥ According to different biparietal diameter grouping, the differences in AV among PD,DTI and PA-PV groups were statistically significant ( P = 0.004),and biparietal diameter was 8~9 cm.There was no significant difference in VA among PD,DTI and PA-PV groups ( P = 0.829). Conclusions PA-PV method,PD method and DTI determination of fetal heart conduction time have the same clinical value,the measured data can be used as a clinical reference value, quantitative analysis of fetal arrhythmia has important clinical potential value.