Intraoperative sonographic measurements of the internal mammary artery as a coronary bypass conduit.

Intraoperative visualization of coronary artery anatomy and morphology is an innovative method to evaluate patients undergoing coronary bypass surgery. With the high frequency ultrasonic technique we were able to measure diameters of internal mammary arteries (IMA) before and after dilatation. Probe dilatation of the IMA led to an increase of the IMA diameter of 46% while balloon dilatation was more successful resulting in an enlargement of 66%. The measurement of the flow rates showed similar changes (95% vs. 275%). Furthermore we were able to reproduce coronary artery lesions by echocardiography which could not be demonstrated in the angiogram.