Aortic arch diameter and its significance in the clinical evaluation of cardiac and aortic enlargements.

OBJECTIVE OF THE STUDY To determine the relevance of the transverse aortic arch diameter in the evaluation of early aortic and cardiac enlargements. SUBJECT AND METHOD A total of 1818 chest radiographs of male and female normotensive and hypertensive Nigerians of age range 4-80 and 10-80 years respectively were used for this study. Ages of subjects were obtained and transverse aortic arch, chest and heart diameters were determined. RESULTS Mean aortic arch diameter for the normotensive groups were noted to be 5.0 +/- 0.5cm, 4.5 +/- 0.4cm and 4.7 +/- 0.5cm for males, females and both sexes respectively while 5.9 +/- 0.9cm, 5.4 +/- 0.6cm and 5.6 +/- 0.8cm for males, females and both sexes respectively were noted in the hypertensive group. Mean values were also generated for the chest and heart diameters. The study reports a mean difference in the aortic arch, heart and cardiothoracic ratio of 15% between the two groups. CONCLUSION Relationship between aortic arch and heart diameter was established and aortic arch diameter was noted to be significant (p< 0.05) in evaluating aortic and cardiac enlargements.