A laser Doppler tissue perfusion monitor was used to measure sternal blood flow before, during, and after mobilization of the internal thoracic arteries in 24 patients undergoing coronary artery bypass grafting. To minimize chest wall injury, a narrow pedicle was mobilized. Bilateral flow data were available from 15 of the 24 patients. Analysis of these 39 studies showed no significant reduction of sternal blood flow as a consequence of mobilization of the internal thoracic arteries except in 2 patients who were both diabetic and obese.