Relationship between age, radiographic normal heart size and cardio-thoracic ratio in a Nigerian population

Abstract

Background: Cardio-vascular disease (CVD) is now on the increase. The precise diagnosis of CVD is of immense clinical importance to the cardiac surgeons, pathologist and also for cardiologists. However, information on normal values for various cardio-vascular structures in Nigeria, a country with the highest population of blacks in the world is sparse. In this regard the age-related radiographic sizes of a Nigerian cohort of patients with non-cardiogenic complaints or consultations were therefore assessed.

Objectives: To evaluate the limits of normal cardiac size in our environment , determine if there was a relationship between the age and size of the heart and to evaluate the relationship between sex and cardiac size and cardio-thoracic ratio.

Design: A cross-sectional study.

Setting: The Radiology department of University of Ilorin Teaching Hospital, Ilorin, North Central Nigeria between January to June 2012.

Subjects: One Hundred patients were consecutively recruited and their chest radiographs examined after fulfilling the inclusion criteria.

Results: Males accounted for 55% of the study population. The age range was 1 month to 73 years, (Mean = 29.3, SD =2.41668). The mean cardiac size was 11.7cm. The average cardiac size for adult males and females, were 11.6cm and 11.5cm respectively while that of thoracic size was 29.0cm and 26.8cm respectively. Correlation between age and cardiac size was 0.66; age and thoracic size was 0.64 and between cardiac size and thoracic size was 0.89. The paired sample t-test for age and cardiac size was less than 0.05 (p value <0.05).

Conclusion: knowing the average values of cardiac size for adult males and females (11.6cm and 11.5cm) and thoracic size (29.0cm and 26.8cm) respectively from this study presents a base line for early detection of variation from normal cardiac measurements in this environment.