1Department of Radiology Seoul National University College of Medicine. 2Department of Thoracic Surgery Seoul National University College of Medicine. 3The Heart Institute Seoul National University College of Medicine.
Published online: January 1, 2001.
ABSTRACT
PURPOSE: The purpose of this study is to evaluate the usefulness of transcutaneous doppler sonography for assess-ment of internal mammary artery graft patency after coronary bypass graft. MATERIALS AND METHODS: Doppler sonography of internal mammary artery was performed in 23 patients, who un-derwent postoperative cardiac catheterization studies. Doppler signals from the proximal part of the internal mammary artery graft were studied from the supraclavicular fossa in the left internal mammary artery and from the high intercostal space in the right internal mammary artery. According to the coronary angiographic studies, internal mammary artery grafts were divided into two groups: Group A with significant stenosis (>75% steno-sis) of the internal mammary artery, and Group B with no significant stenosis of the internal mammary artery. The diastolic/systolic peak velocity ration and diastolic/systolic flow-volume ratio between the two groups were analyzed. RESULTS: Doppler spectrum of the internal mammary artery were obtained from 21 patients, but not from 2 pa-tients, because of the poor sonic window. According to the coronary angiographic studies, there were 6 cases in Group A and 16 cases in Group B. The diastolic/systolic peak velocity ration and diastolic/systolic flow-volume ration in Group A were significantly smaller than in group B(p<0.05). A diastolic/systolic peak velocity ratio <0.4 predicted significant internal mammary artery graft stenosis(>75% stenosis) with a sensitivity and speci-ficity of 100% and 75% respectively. A diastolic/systolic flow-volume ratio <0.45 predicted significant internal mammary artery graft stenosis (>75% stenosis) with a sensitivity and specificity of 83% and 88% respectively. CONCLUSION: Transcutaneous doppler sonography is useful for non-invasive assessment of the internal mammary artery graft patency.