测量上下肢收缩压差值在新生儿主动脉畸形诊断中的价值

Role of systolic blood pressure gradient of limb test in diagnosing neonatal aorta anomaly

目的探讨检测上下肢血压的收缩压差值（SBPG）在诊断新生儿主动脉畸形（AoA）中的价值。方法前瞻性收集2013年1月至2015年12月在广东省人民医院住院疑为AoA的重症先天性心脏病新生儿的上下肢血压并计算右上肢和下肢血压的SBPG的数据，将测量结果与AoA诊断金标准（心脏超声或CT）比较。选择5 mmHg（1 mmHg＝0.133 kPa）、10 mmHg、15 mmHg、20 mmHg作为截断值，计算不同截断值下SBPG检测的灵敏度、特异度、漏诊率和误诊率。通过构建受试者工作特征（ROC）曲线并计算曲线下面积选择最佳的SBPG截断值。结果664例患儿中，67例通过金标准检测确诊AoA。AoA组和非AoA组的右上肢收缩压、下肢收缩压及SBPG分别为（88.0±20.4） mmHg比（73.4±9.3） mmHg（P〈0.01）、（66.1±10.1） mmHg比（69.0±9.7） mmHg（P〉0.05）和（22.6±17.8） mmHg比（2.3±4.8） mmHg（P〈0.01）。SBPG为5 mmHg、10 mmHg、15 mmHg、20 mmHg截断值下分别筛查出31例（46.3%）、31例（46.3%）、27例（40.3%）、21例（31.3%）AoA患儿，漏诊36例（53.7%）、36例（53.7%）、40例（59.7%）、46例（68.7%）（P〈0.01）。各组的特异度分别为94.1%、99.5%、99.7%和100.0%；ROC曲线下面积为0.656、0.722、0.695和0.657（P〈0.01）。结论测量上下肢收缩压差值能够筛查出近半数AoA患儿。选择SBPG截断值10 mmHg能够最大程度地发现AoA患儿，且误诊率低。

Objective To determine the effectiveness of systolic blood pressure gradient between the right arm and the right leg（SBPG） tests in the diagnosis of neonatal aorta anomaly（AoA）. Methods The SBPG of infants suspected of having critical congenital heart diseases were collected prospectively,who were admitted to Guangdong General Hospital from January 2013 to December 2015. The results of SBPG test were compared with those of echocardiography or cardiac computed tomography （golden standard）. The rates of true positive, true negative, false positive, false negative were calculated under cutoff values of 5 mmHg（ 1 mmHg =0. 133 kPa） , 10 mmHg, 15 mmHg and 20 mmHg, respectively. Receiver operating characteristic （ROC） curves was used to compare tests of different cutoff and the areas under the ROC curve were also calculated. Results Among 664 enrolled infants,67 cases were confirmed by golden standard test. The systolic blood pressure in the fight arm, the legs and SBPG in AoA group and non - AoA group were （88.0±20.4） mmHgvs. （73.4±9.3） mmHg （P〈0.01）,（66.1 ±10.1） mmHgvs.（69.0±9.7） mmHg（P〉 0. 05 ） and （22.6 ±17. g） mmHg vs. （2.3 ±4.8） mmHg（ P 〈0. 01 ） ,respectively. In these patients,31 eases（46.3% ）, 31 cases（46.3% ） ,27 cases（40. 3% ） and 21 cases（31.3% ） were diagnosed of AoA,and 36 cases（53.7% ） ,36 cases （ 53.7 % ） ,40 cases （ 59.7 % ）, and 46 cases （ 68. 7 % ） were missed by SBPG tests of 5 mmHg, 10 mmHg, 15 mmHg and 20 mmHg,respectively （P 〈0.01 ）. The rates of true negative among those groups were 94.1% ,99.5% ,99.7% and 100.0% ,and the areas under ROC curve were 0. 656,0. 722,0. 695 and 0. 657, respectively （P 〈 0.01 ）. Conclusions Almost half of AoA infants could be screened out by SBPG test. The cutoff of 10 mmHg could probably be used to screen potential AoA infants,with higher true positive rate and lower false positive rate.