DUPLEX SONOGRAPHY OF THE INTERNAL THORACIC ARTERY - PREOPERATIVE ASSESSMENT

Ultrasonic duplex: scanning was used to examine 211 internal thoracic arteries. The investigated vessels were classified as normal, abnormal , and occluded. The results of the duplex examination were compared wi th angiography as the reference method. The diameter measurements show ed virtually no differences between the two methods. Normal internal t horacic arteries showed a continuous decrease of the systolic flow vel ocities from proximal to distal and a narrow to moderate spectral how curve, whereas arteries classified as abnormal showed a velocity profi le distinct from that-in particular, no decrease of the systolic peak velocities and an increased spectral broadening during systole with pe ak frequencies greater than 4 kHz at 60 degrees (>1.2 m/sec). In occlu ded vessels no flow could be detected. The majority of changes were fo und in the proximal part of the internal thoracic artery. Ah lesions w ere detected by duplex sonography. Six normal vessels were misjudged a s abnormal by the duplex method. The sensitivity, specificity, and acc uracy of duplex sonography compared with angiography as the reference method were 100% (95% CI, 74.4% to 100%), 96.9% (95% CI, 93.2% to 98.8 %), and 97.2% (95% CI, 93.6% to 98.8%), respectively. Duplex sonograph y is a reliable, noninvasive technique for the preoperative assessment of the internal thoracic artery. It allows the detection of potential atherosclerotic changes in the internal thoracic artery and the asses sment of adequacy of caliber and flow.