Filho José G Lobo, Leitão Maria C A, Forte Antonio J V, Filho Heraldo G Lobo, Silva André A, Bastos Eduardo S, Murad Henrique
Department of Heart Surgery of the Institute of Heart and Lung-ICORP, 60115280 Fortaleza, Ceará, Brazil.
Tex Heart Inst J. 2006;33(4):430-6.
In order to evaluate the left internal thoracic artery flow pattern, when the vessel is used as a graft to supply the left coronary artery system, we evaluated flow by Doppler measurement, both at rest and under dobutamine stress. There were 2 groups of 20 patients each: group A patients received only a left internal thoracic artery graft to the left anterior descending artery, and group B patients received a pedicled left internal thoracic artery graft associated with a vein graft, which together supplied the left anterior descending artery and another branch of the left coronary artery. Angiography showed patent grafts in all patients from both groups. The following characteristics were evaluated: systolic flow, diastolic flow, total flow, total flow under stress/total flow at rest ratio, systolic peak velocity, diastolic peak velocity, and systolic peak velocity/diastolic peak velocity ratio. In group A, the total flow was 45.5 +/- 21.6 mL/min at rest and 68.3 +/- 32.9 mL/min under stress. In group B, the total flow was 98.2 +/- 50.4 mL/min at rest and 175.7 +/- 79.2 mL/min under stress. Comparison between groups showed a total flow increase in group B of 115.8% (P=0.0002) at rest and 157.2% (P <0.0001) under stress. The other characteristics were also statistically significant, except systolic flow, total flow under stress/total flow at rest ratio, and systolic peak velocity. Our results showed that the left internal thoracic artery sufficiently supplies regional myocardium at rest and during exercise (stress), demonstrating its great adaptability in response to demand.
为了评估左胸廓内动脉作为移植血管为左冠状动脉系统供血时的血流模式，我们通过多普勒测量在静息状态和多巴酚丁胺负荷状态下评估血流情况。研究共两组，每组20例患者：A组患者仅接受左胸廓内动脉至左前降支的移植，B组患者接受带蒂左胸廓内动脉移植联合静脉移植，共同为左前降支和左冠状动脉的另一分支供血。血管造影显示两组所有患者的移植血管均通畅。评估了以下特征：收缩期血流、舒张期血流、总血流、负荷状态下总血流/静息状态下总血流比值、收缩期峰值流速、舒张期峰值流速以及收缩期峰值流速/舒张期峰值流速比值。A组静息状态下总血流为45.5±21.6 mL/min，负荷状态下为68.3±32.9 mL/min。B组静息状态下总血流为98.2±50.4 mL/min，负荷状态下为175.7±79.2 mL/min。两组间比较显示，B组静息状态下总血流增加115.8%（P = 0.0002），负荷状态下增加157.2%（P < 0.0001）。除收缩期血流、负荷状态下总血流/静息状态下总血流比值和收缩期峰值流速外，其他特征也具有统计学意义。我们的结果表明，左胸廓内动脉在静息和运动（负荷）状态下均能充分供应局部心肌，显示出其对需求的良好适应性。
