Analysis of transit time flow of the right internal thoracic artery anastomosed to the left anterior descending artery compared to the left internal thoracic artery.

Introduction: We evaluated with transit time flow the performance of the right and left thoracic arteries when used as a graft for the left anterior descending artery.

Methods: Fifty patients undergoing surgery for myocardial revascularization without cardiopulmonary bypass were divided into two groups. In group A patients received graft of right internal mammary artery to the anterior interventricular branch. In group B patients received graft of left internal mammary artery to the same branch. At the end of the operation the flow was assessed by measuring transit time.

Results: In group A, mean age was 60.6 ± 9.49 years. The average height and weight of the group was 80.4 ± 10.32 kg and 169.2 ± 6.86 cm. The average number of grafts per patient in this group was 3.28 ± 1.49. The mean flow and distal resistance obtained in right internal thoracic artery was 42.1 ± 23.4 ml/min and 2.8 ± 0.9 respectively. In group B, the mean age was 59.8 ± 9.7 years. The average height and weight of this group was 77.7 ± 14.22 kg and 166.0 ± 8.2 cm. The average number of grafts per patient in this group was 3.08 ± 0.82. The mean flow and distal resistance observed in this group was 34.2 ± 19.1 ml/min and 2.0 ± 0.7. There were no deaths in this series.

Conclusion: Right internal mammary artery presented a similar behavior to left internal mammary artery when anastomosed to the anterior interventricular branch of the left coronary artery. There was no statistical difference between the measured flow obtained between both arteries.