1Department of Radiology, the Institute of Radiation Medicine, Seoul National University College of Medicine. 2Department of Thoracic Surgery, Seoul National University College of Medicine.
Published online: January 1, 2001.
ABSTRACT
PURPPOSE: To assess useful Doppler ultrasonographic parameters in the follow-up evaluation of left internal mammary artery after coronary artery bypass graft. MATERIALS AND METHODS: High frequency (10MHz linear probe) ultrasonography was performed at supraclavicular fossa on 25 patients (mean age, 61 years) who had had left internal mammary artery (IMA) grafts to the left anterior descending artery and had angiographically no evidence of graft vessel stenosis and on 26 patients (mean age, 62 years) who had triple-vessel disease at coronary angiography. Doppler velocity profile, peak systolic velocity (PSV), peak diastolic velocity (PDV), PDV/PSV, internal diameter (mm), flow volume (ml/min), resistive index (RI), pulsatile index (PI) were obtained. The results were analyzed for the significant difference between right vs. left IMA and preoperative group vs. postoperative group. RESULTS: There was no significant difference between right vs. left IMA in preoperative group. After left IMA graft, right IMA revealed increase of PSV, PDV and flow volume. Doppler velocity profiles of left IMA grafts were obtained and in all cases, a biphasic pattern of blood flow was recorded and significant increase of PDV, PDV / PSV, PI was obtained. PDV/PSV > 0.4 predicted postoperative change with specificity of 100% and sensitivity of 84%. CONCLUSION: After coronary artery bypass graft, Doppler ultrasonography of left internal mammary at left supraclavicular fossa shows significant change in flow velocity profile and PDV/PSV ratio. These Doppler ultrasonographic parameters may be useful in the follow-up evaluation of IMA after coronary artery bypass.