Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.
Ultrasound Obstet Gynecol. 2010 Nov;36(5):561-6. doi: 10.1002/uog.7532.
To investigate the diagnostic precision of three Doppler methods in their ability to predict postnatal first-degree atrioventricular (AV) block.
This was a prospective, observational study carried out from December 1999 to March 2008, including 95 fetuses of anti-SSA/Ro positive mothers undergoing weekly fetal echocardiograms at 18-24 weeks' gestation. Doppler-derived AV time intervals for left ventricular inflow (MV), inflow and outflow (MV-Ao) and superior vena cava a-wave to aortic flow (SVC-Ao) were compared with the PR interval on postnatal electrocardiography. Reference values for MV intervals were established from 102 healthy fetuses, with previously published reference ranges used for the two other methods. Bayesian and receiver-operating characteristics (ROC) curve analyses were performed.
The prevalence of first-degree AV block at birth was 13.8%. Using a cut-off at the upper 95% confidence limit, MV-Ao and SVC-Ao time intervals had a sensitivity of 91.7%, and negative predictive value and negative likelihood ratio of 98.4% and 0.10, respectively. The corresponding positive predictive value/positive likelihood ratio for MV-Ao and SVC-Ao were 42.3%/4.5 and 47.8%/5.7, respectively. The areas under the ROC curve (AUC) for MV-Ao and SVC-Ao were 0.87 and 0.89, respectively (both P < 0.001), with generated cut-offs for abnormal AV time intervals at 134-138 and 132-138 ms. MV time intervals using a cut-off at the upper 95% confidence limit had a sensitivity of just 50% and an AUC of 0.74 (P < 0.01).
The MV-Ao and SVC-Ao Doppler methods make it possible to identify nearly all fetuses with first-degree AV block at birth and to exclude conduction disturbances in the case of a normal AV time measurement but at the cost of a positive predictive value of 50%.
探讨三种多普勒方法预测新生儿一度房室（AV）阻滞的诊断精度。
这是一项前瞻性、观察性研究，于 1999 年 12 月至 2008 年 3 月进行，纳入 95 例抗 SSA/Ro 阳性母亲的胎儿，这些胎儿在妊娠 18-24 周时每周进行胎儿超声心动图检查。比较左心室流入（MV）、流入和流出（MV-Ao）以及上腔静脉 a 波至主动脉血流（SVC-Ao）的多普勒衍生 AV 时间间隔与新生儿心电图的 PR 间隔。MV 间隔的参考值是从 102 例健康胎儿中建立的，另外两种方法则使用之前发表的参考范围。进行贝叶斯和接收者操作特征（ROC）曲线分析。
出生时一度 AV 阻滞的患病率为 13.8%。使用上限 95%置信区间的截断值，MV-Ao 和 SVC-Ao 时间间隔的敏感性为 91.7%，阴性预测值和阴性似然比分别为 98.4%和 0.10。MV-Ao 和 SVC-Ao 的相应阳性预测值/阳性似然比分别为 42.3%/4.5 和 47.8%/5.7。MV-Ao 和 SVC-Ao 的 ROC 曲线下面积（AUC）分别为 0.87 和 0.89（均 P<0.001），异常 AV 时间间隔的截断值分别为 134-138 和 132-138 ms。使用上限 95%置信区间截断值的 MV 时间间隔敏感性仅为 50%，AUC 为 0.74（P<0.01）。
MV-Ao 和 SVC-Ao 多普勒方法可用于识别几乎所有出生时存在一度 AV 阻滞的胎儿，并在 AV 时间测量正常的情况下排除传导障碍，但阳性预测值为 50%。
