Duplex Waveform Analysis of the Subclavian Artery in a Case with Internal Mammary Steal Syndrome

In patients undergoing chronic hemodialysis through an arteriovenous fistula (AVF), coronary insufficiency may occur if the patient undergoes coronary artery bypass grafting (CABG) using the ipsilateral internal mammary artery (left internal mammary artery [LIMA] or right internal mammary artery [RIMA]). Creation of a new AVF after CABG should therefore avoid using the arm ipsilateral to the side where the internal mammary artery was used. In cases where coronary syndrome appears when this advice was not followed, treatment should be offered aiming to overcome the hemodynamic interference between the diminished coronary supply through the LIMA/RIMA and the excessive flow through the AVF. By using subclavian artery (SCA) waveform analysis on a duplex scan, a noninvasive evaluation of the flow through the SCA ipsilateral to the side of the mammary artery and the fistula can be performed both with the patent (functioning) and closed fistula. Waveform analysis can enlighten the phenomena of steal syndrome through the internal mammary artery and is highly recommended in this small and unusual group of patients.