Anatomical and functional assessment of single left internal mammary artery versus arterial T-grafts 12 years after surgery

Abstract

We determined whether ultrasonographic left internal mammary artery (LIMA) findings correspond with 64 multislice computed tomography (MSCT) in patients 12 years after coronary artery bypass grafting. We included 34 patients (63.2±9.2 years), 16 with conventional single LIMA (group I) and 18 arterial T-grafts (group II), in a cross-sectional study. Patients underwent transthoracic proximal LIMA ultrasonography at rest and during the Azoulay maneuver, transthoracic echocardiography of the left ventricle and 64-MSCT, 11.5±1.4 years postoperatively. MSCT scans showed three string sign LIMA grafts (19%) in group I and three distal string sign LIMA grafts (17%) and 16 occluded T-graft anastomoses (22%) in group II. LIMA diameters and areas are significantly larger in group II in the origin, 3.5±0.7 vs. 2.5±0.5 mm, P=0.00007 and 0.09±0.04 vs. 0.05±0.02 cm 2, P=0.00019 and in the third intercostal space, 3.4±0.7 vs. 2.5±0.5 mm, P=0.00009 and 0.09±0.03 vs. 0.05±0.02 cm 2, P=0.000047. Most ultrasonographic LIMA findings do not differ between the groups. Thus, proximal LIMA diameters and areas are significantly larger in T-grafts and ultrasonographic variables equalize between the groups at rest and during the Azoulay maneuver 12 years after surgery.