Applied Anatomic Study Of Internal Thoracic Artery With Ultrasonic Examination

Objective:The data obtained by utilizing color Doppler ultrasonography and anatomic observation of internal thoracic artery is provided for coronary artery bypass grafting.Methods: The ITA and coronary artery were observed and measured on 30 adult cadavers which 20 are male. 131 cases of normal subjects including 78 male and 53 female, mean age 50.4 ± 6.7 years are measured by ultrasonograph .Experimental Apparatus and Parameters: GE color ultrasonograph apparatus ( American GE company) is applied in this study. Set the machine to the 'blood vessel' condition. Probe frequency ranged from 10 to 12 MHz and color Doppler frequency is 2.0~4.0MHz. The measured position is sternum side and supraclavicular fossa. The inner diameter and blood flow velocity of Internal Thoracic Artery : Vmax, Vmin, Vd, TAMAX , RI, PI of Internal Thoracic Artery are measured. Statistic analysis: All the data are dealed with SPSS. 11.5 software and showed with x ±SD . T-test analysis is applied in comparison of different groups.Results: The mean length of the ITA was 16.04cm from its commencement to the end. The mean diameter of the left was 2.8mm, 2.4mm ,2.2mm and 2.0mm at its commencement, the second, the third and the end respectively and the mean diameter of the right was 2.7mm, 2.3mm ,2.1mm and 1.9mm correspondingly. The mean diameter of the anterior interventricular branch, the circumflex branch, the left marginal branch, the diagonal branch, the right coronary artery and the posterior interventricular branch is 3.5mm, 3.0mm,1.9mm,2.0mm,3.5mm and 2.1mm respectively.There are no significant difference between both sides in diameter, Vmax, Vmin, Vd, TAMAX, RI and PI. Diameter of the ITA become thinner gradually from its commencement to the end, Vmax, Vmin, Vd and TAMAX descend gradually also, but RI and PI are not changed.Conclusions:1.The diameter of the ITA is approximated to that of the main branches of the coronary artery. Therefore the located graft ITA was a suitable conduit for coronary revascularzation of the anterior and lateral walls of the heart;As dislocated graft it would bridge between ascending aorta and anycoronary artery.2.Color Doppler ultrasonic is useful to explore structure and Hemodynamics changes of Internal Thoracic Artery.3.The best position to examine two dimensional pararmeter of Internal Thoracic Artery is sternum side.4.The best position to examine Hemodynamics pararmeter of Internal Thoracic Artery is supraclavicular fossa.5.Color Doppler energy is of significant value in clearly displaying Internal Thoracic Artery.