ABSTRACT
Background:The gold standard for pulmonary artery pressure measurement is right heart catheterization but its invasive nature precludes its routine use. Main pulmonary arterial trunk calibreincrease is a strong indicator of underlying pulmonary arterial hypertension. MDCT can accurately measure the diameter of main pulmonary artery. The objective of the study was to establish the normative values of main pulmonary artery caliber using contrast enhanced CT and try to ascertain any significant difference in main pulmonary artery calibers between two genders and correlation of age and main pulmonary artery diameter. Methods:Contrast enhanced CT images of 462 subjects were analysed on a PACS workstation monitor and widest diameter perpendicular to long axis of the main pulmonary artery as seen on reformatted axial image was measured with electronic caliper tool at the level of the main pulmonary artery bifurcation.Results:The mean main pulmonary artery diameter in females was 22.54±2.19 mm and 23.34±3.06 mm in males. The mean pulmonary artery diameter in males was larger than females with statistically significant difference seen (p<0.05). The correlation coefficient between age of whole sample and their mean main pulmonary artery was found to be 0.1006 with no statistically significant difference.Conclusions:There is a statistically significant difference in the mean main pulmonary artery calibre between males and femaleswith no strong correlation between the age and mean main pulmonary artery calibre. Further studies are warranted to find the complex interaction between main pulmonary artery diameter and sex, age and body mass index