Mensah Y B, Mensah K, Asiamah S, Gbadamosi H, Idun E A, Brakohiapa W, Oddoye A
Department of Radiology, Korle Bu Teaching Hospital, Korle Bu Accra.
Public Health Consultant, P. O. Box GP 15533, Kumasi.
Ghana Med J. 2015 Sep;49(3):159-64. doi: 10.4314/gmj.v49i3.6.
Cardiothoracic ratio is a simple and cheap tool in the estimation of heart size. It is a useful index of cardiac size evaluation, and a value of 50% is generally considered to indicate the upper limit of normal.
This study is to ascertain the normal mean value in cardiothoracic ratio of Ghanaians using chest radiography to serve as baseline for screening for cardiomegaly.
Standard postero-anterior radiographs of the -clients/patients were used in the study. The cardiothoracic ratio (CTR) was obtained by dividing the transverse cardiac diameter [sum of the horizontal distances from the right and left lateral-most margins of the heart to the midline (spinous processes of the vertebral bodies)] by the maximum internal thoracic diameter. Systematic sampling with appropriate inclusion and exclusion criteria were used to obtain a sample size of 1989.
The mean transverse cardiac diameter and cardiothoracic ratio increased with age. The transverse thoracic diameter increased with age until the sixth decade when it reduced with age. The mean CTR increased gradually with age with females having greater values than males. The mean CTR of the study population were 0.459, 0.467 and 0.452 for the general population, females and males respectively.
This study has been able to establish 0.459 as the mean CTR values for Ghanaians. It has also shown the relationship between age and clients/patient's cardiothoracic ratio which compares favourably with findings of a similar study in Nigeria, a neighbouring country in the West African sub region with similar ethnic and social structure.
心胸比率是评估心脏大小的一种简单且廉价的工具。它是评估心脏大小的一个有用指标，一般认为50%的值表明正常上限。
本研究旨在通过胸部X线摄影确定加纳人心胸比率的正常平均值，作为心脏扩大筛查的基线。
本研究使用了研究对象/患者的标准后前位X线片。心胸比率（CTR）通过将心脏横径[从心脏左右最外侧边缘到中线（椎体棘突）的水平距离之和]除以胸廓最大内径来获得。采用系统抽样并结合适当的纳入和排除标准，获得了1989个样本量。
心脏横径平均值和心胸比率随年龄增长而增加。胸廓横径随年龄增长而增加，直到第六个十年，之后随年龄下降。平均心胸比率随年龄逐渐增加，女性的值高于男性。研究人群的平均心胸比率，总体人群、女性和男性分别为0.459、0.467和0.452。
本研究已确定0.459为加纳人的平均心胸比率值。它还显示了年龄与研究对象/患者心胸比率之间的关系，这与在尼日利亚（西非次区域的一个邻国，具有相似的种族和社会结构）进行的一项类似研究的结果相比具有优势。
