Sex Dimorphism of the Heart Diameters and Cardiothoracic Ratios in a Normal Nigerian Population.
Objective: To determine gender associated differences in the cardiothoracic ratio (CTR) and heart diameters in a normal Nigerian population. Subject and Method: The normal heart diameters and cardiothoracic ratios were measured from posteroanterior (PA) chest radiographs of healthy 510 male and 508 female Nigerians of age range 4 - 80 years. Results: Mean heart diameter of 13.0+ 1.5cm, 12.3+1.3cm and 12.6+1.5cm for males, females and both respectively and mean CTR values of 46.2 + 4.1, 47.2 + 4.4 and 46.7 + 4.3 of males, females and both respectively were noted in the studied population. . The study reports a consistent sex difference in heart diameter of 0.5 to 1.2cm and 1.0 to 3.1cm in chest diameter. It apportions a difference of up to 37% in heart size ratio to gender difference. Discussion/Conclusion: The study established statistically significant differences in the heart diameter and CTR of the studied population, which is based on gender.
Keywords: Sex dimorphism, cardiothoracic ratio, heart diameter.
Nigerian Medical Journal Vol. 48 (1) 2007: pp. 24-26