Noninvasive measurement of left internal mammary artery bypass graft flow by duplex Doppler echocardiography from the supraclavicular fossa.

To test the ability of duplex Doppler echocardiography from the supraclavicular fossa in detecting the left internal mammary artery (LIMA) graft flow and to verify the flow velocity measurement with this method, we studied 12 consecutive patients who underwent coronary artery bypass graft surgery with the LIMA graft. Duplex Doppler echocardiography detected the LIMA graft flow in 11 (92%) of the 12 patients. In these patients, simultaneous supraclavicular duplex Doppler and Doppler catheter measurements of the LIMA graft flow were performed. There were significant correlations in systolic peak velocity (r = 0.84, p < 0.01) and diastolic peak velocity (r = 0.79, p < 0.01) between the supraclavicular and Doppler catheter methods. There were also significant correlations in the diastolic to systolic peak flow velocity ratio (r = 0.86, p < 0.01) and diastolic fraction (r = 0.90, p < 0.01) between the supraclavicular and Doppler catheter methods. Thus, duplex Doppler echocardiography from the supraclavicular fossa is useful in the detection of the LIMA graft flow and permits accurate noninvasive measurement of the LIMA graft flow.