USE OF COLOR DOPPLER IMAGING IN ASSESSMENT OF PREOPERATIVE AND POSTOPERATIVE FLOW CHARACTERISTICS OF INTERNAL THORACIC ARTERY IN MYOCARDIALREVASCULARIZATION

Between January 1993 and February 1993, the left internal thoracic art eries of 40 consecutive patients scheduled for aortocoronary bypass op eration were examined by transthoracic B-mode imaging. Perioperative m easurements correlated well with preoperative noninvasive measurements (r = 0.914). In the postoperative period, B-mode images could not be obtained in 17 (44.7%) of 38 patients. Adequate Doppler spectra of the internal thoracic artery were obtained in all patients preoperatively and in 36 (94.7%) of 38 patients postoperatively. Preoperatively a tr iphasic wave form was obtained with a large systolic peak followed by small reversed and diastolic components in all patients. Postoperative ly this triphasic wave form had been converted into a combined systoli c-diastolic wave form. In all patients peak systolic velocity of the i nternal thoracic artery decreased (96.4 +/- 15.3 vs 64.2 +/- 18.9 cm/s ec., P < 0.05), and peak diastolic velocity increased (21.7 +/- 8.8 vs 28.3 +/- 11.2 cm/sec., P < 0.05) significantly in the postoperative p eriod as compared with the preoperative values. A slight decrease in p eak systolic and diastolic velocities was detected at twelve months po stoperatively. This study indicates that transthoracic B-mode imaging and Doppler spectrum analysis are reliable techniques in the preoperat ive and postoperative assessment of the internal thoracic artery in my ocardial revascularization.