Ultrasonographic and DSCT scan analysis of single LIMA versus arterial T grafts 12 years after surgery

Aim. The aim of this study was to investigate long-term graft outcome in patients with left internal mammary artery to left anterior descending coronary artery (LIMA-LAD) and T-grafts by ultrasonography and dual source computed tomography (DSCT) and to analyse if ultrasonography can determine graft patency. Methods. Thirty-two patients, 28 males, 50.8 +/- 8.8 years at operation, were studied. Fifteen patients with single LIMA-LAD and additional vein grafts (group I) and 17 patients with LIMA-free right internal mammary artery (FRIMA) T-grafts (group II) underwent DSCT, transthoracic ultrasonography of the LIMA and an electrocardiogram. Differences were tested with unpaired and paired t tests. Results. In group I, 4.1 +/- 1.1 and in group II, 4.5 +/- 1.1 anastomoses/patients were performed. DSCT showed three string sign LIMA (20%) grafts and six occluded venous anastomoses (13%) in group I and three (distal) string sign LIMA grafts (18%), seven occluded LIMA anastomoses (23%) and nine occluded FRIMA anastomoses (23%) in group II. Ultrasonographic variables in the proximal part of the LIMA graft did not differ between the groups. No effect was found for proximal string sign LIMA grafts in ultrasonographic graft performance. Conclusion Ultrasonography cannot distinguish between string sign and patent single LIMA or T-grafts nor demonstrate distal anastomosis patency in T-grafts 12 years after surgery.