[Noninvasive assessment of left internal thoracic artery graft patency using transthoracic echocardiography].

To evaluate the utility of transthoracic echocardiography (TTE) for assessing the long-term patency of left internal thoracic artery (LITA) grafts, 36 patients who had coronary artery bypass grafting (CABG) were examined simultaneously for graft flow velocity by TTE and by graft angiogram. The flow velocity in the LITA graft was clearly visualized by TTE in 25 patients from the left supraclavicular echo view. On the basis of the angiogram, the sensitivity and specificity of TTE in the diagnosis of LITA graft patency were 71.4% and 100%, respectively. These 25 patients (mean follow-up time after CABG-29.6 months) were divided into 3 groups according to their preoperative diagnosis and the presence of grafts stenosis by angiogram as follows: APS(-), angina pectoris without graft stenosis in 15 cases; APS(+), angina pectoris with graft stenosis in 2 cases; OMI, old myocardial infarction without graft stenosis in 8 cases. The peak flow velocity D/S ratio and time velocity integral D/S ratio in the APS(-) group (2.48 +/- 0.73, 3.21 +/- 0.89) were significantly (p < 0.01) higher than those in the APS(+) group (0.30 +/- 0.23, 0.35 +/- 0.21) or in the OMI group (0.96 +/- 0.44, 0.87 +/- 0.51). Peak flow velocity D/(S+D) and time velocity integral D/(S+D) ratios in the APS(-) group (0.70 +/- 0.05, 0.75 +/- 0.06) were significantly (p < 0.01) higher than those in the APS(+) group (0.22 +/- 0.14, 0.25 +/- 0.11) or in the OMI group (0.46 +/- 0.17, 0.43 +/- 0.18).(ABSTRACT TRUNCATED AT 250 WORDS)