Cardiothoracic Ratio and Prevalence of Cardiomegaly among Adult Patients in FMC Ebute Metta, Nigeria

Abstract

Background: Cardiothoracic ratio (CTR) is a common and usually first-line method for the assessment of cardiac size and evaluation for cardiac enlargement (cardiomegaly), particularly in developing countries. Aims: The aim of the study was to establish the average cardiothoracic ratio, transverse cardiac diameter (TCD) and transverse thoracic diameter (TTD) of patients who perform a PA chest radiograph in Federal Medical Center (FMC) Ebute Metta, located in Lagos state Nigeria. We also aim to determine the prevalence of radiographic cardiomegaly using a cardiothoracic ratio of >0.50 as cutoff. Methodology: The study was a retrospective descriptive and analytical cross-sectional study utilizing chest radiographs obtained in the radiology department of the FMC Ebute Metta. A total of 490 radiographs (belonging to 252 women and 248 men) were included in this study. Results: The average CTR, TCD and TTD in this study were 0.476 ± 0.052, 138.17 ± 16.89mm and 291.11 ± 24.68mm respectively. The mean CTR in females (0.489 ± 0.052) in this study was significantly higher (P <0.001) than that of males (0.461 ± 0.047), while the mean TCD (141.50mm ±16.85mm in males, compared to 135.03mm ± 16.33mm in females) and mean TTD (307.12 ± 20.77mm in males, compared to 275.99 ± 17.53mm in females) were significantly higher in males (P <0.001). The prevalence of cardiomegaly (CTR > 0.50) in this study was 27.3%. The prevalence of cardiomegaly was significantly higher in females (36.5%) compared to males (17.6%). The prevalence of cardiomegaly significantly increased with age, with the highest prevalence in the 71-80 years’ group (59.1%). Conclusion: This study has established baseline values for cardiothoracic ratio (CTR), transverse cardiac diameter (TCD), and transverse thoracic diameter (TTD) in an adult population in Lagos, Nigeria. Further multicenter, prospective studies incorporating echocardiographic correlation are warranted to refine diagnostic thresholds and optimize the use of chest radiography in cardiovascular disease prevention and management in Nigeria.