婴幼儿先天性心脏病心胸比率两种测量方法比较

目的分析呼吸对婴幼儿先天性心脏病患者心胸比率测量结果准确性的影响,探讨该特殊人群心胸比率测量的方法。方法连续收集3岁以下先天性心脏病患者45例,采集连续透视序列,在吸气末和呼气末冻结图像,分别采用右膈顶法、第九肋内缘法(简称九肋法)测量胸廓宽径及心脏横径,计算吸气末和呼气末的差值,比较吸气和呼气对两种方法测量结果的影响。结果胸廓宽径在吸气末和呼气末的变化量,九肋法测量结果显著低于右膈顶法(t=7.41,P<0.001)。心脏横径在吸气末和呼气末的变化量为(1.08±0.65)mm,受呼吸的影响较小,吸气末心脏横径仍大于呼气末心脏横径的患者占40%(18/45)。结论对于不能配合屏气的婴幼儿患者,心胸比率测量中,呼吸主要影响胸廓宽径。选择九肋法测量心胸比率受呼吸的影响小,稳定性高,有利于心影大小动态变化的对比观察。

Comparison on the two methods for measuring cardiothoracic ratio of infant and young children patients with congenital heart disease

Objective To analyze the influence of respiration on cardiothoracic ratio of infant and young children with congenital heart disease and to explore the method of measuring cardiothoracic ratio in the special populations.Methods The 45 cases with congenital heart disease in children under 3 years old continuously were collected.Freezed the perspective images at the end of the inspiration and expiration were sampled,the width of thorax and heart was measured with the right diaphragm top and "the ninth costal bone method" respectively.The changes of the thoracic width and cardiac width between end inspiration and end expiration was obtained.So the influence of respiration on measurement results under the two methods could be compared.Results The changes of the thoracic width between end inspiration and end expiration measured by the ninth costal bone method was significantly lower than the right diaphragm top method,the difference was statistically significant(P<0.001).The change of the cardiac width between end inspiration and end expiration was(1.08±0.65) mm,less affected by breathing.The cases with the larger cardiac width at end inspiration than at end expiration accounted for 40%(18/45).Conclusion For the younger children who could not cope with breath-hold,respiration mainly impacted on thoracic width when measuring cardiothoracic ratio."The ninth costal bone method" is conducive to contrast observation for the dynamic changes in the size of the heart with low interference by respiration and with high stability.