Background: Preoperative diagnosis of coronary ostial deformities is also very crucial in congenital heart diseases such as Fallot’s tetralogy and transposition of arterial supply. Anatomical understanding of coronary orifices may reduce invasive procedure morbidity and mortality.The study's objectives were:1) Measure the diameters of the coronary ostia and coronary artery roots. 2) Measure the distance between the coronary ostia and the aortic sinus.3)To measure the distance of coronary ostia to the commissures of aortic leaflets. 4) To examine the relationship between the coronary ostia and the sinotubular junction.5) Note any accessory or single ostia.