[Internal thoracic artery bypass--basic principles of Doppler ultrasound for pre- and postoperative diagnosis].

During the last 25 years the internal thoracic artery has become a well established conduit for coronary revascularization. Next to angiography, duplex-sonography is increasingly used as a non-invasive imaging procedure for the evaluation of this graft vessel. Preoperative investigation in 117 patients has yielded a high level of agreement between angiography and duplex-sonography. While the preoperative flow-pattern is dominated by systolic flow as it is typical for vessels supplying skeletal muscle, the postoperative findings show an adaptation to the coronary vascular bed as the diastolic flow increases. These non-invasive measurements are well matched with invasive intravascular recordings. Coronary angiography and duplex-sonography of the internal thoracic artery yielded comparable findings in respect to the procedural result. Considering the increasing use of the internal thoracic artery in coronary artery bypass surgery, this non-invasive method should gain increasing relevance.