NONINVASIVE ESTIMATION OF THE INTERNAL MAMMARY ARTERY BYPASS GRAFT PATENCY - A 6-YEAR FOLLOW-UP

Echo Doppler of the internal mammary artery (IMA) can be considered a good clinical and diagnostic tool in detecting the flow in the IMA byp ass graft. The aim of the present study was to evaluate the reliabilit y of transcutaneous echo-Doppler ultrasonography in the detection of e arly and long-term pathologies of the IMA bypass graft. The study was carried out on 161 consecutive patients (127 men and 34 women, mean ag e fifty-two +/- ten years) who had undergone surgical myocardial revas cularization by anastomosis of the left IMA pedicle to the left anteri or descending coronary artery. All patients underwent echo-Doppler exa mination in resting conditions, during forced hyperventilation and Val salva maneuver four times per year. Supine exercise test was performed annually for five years, and selective angiography of the IMA graft ( IMAg) was done when symptoms and/or conventional stress test and/or ec ho-Doppler examination required it. The results showed that, for anato mic reasons only, in 87% (140 patients), it was possible to study the IMAg. In these patients, 16 stenoses greater-than-or-equal-to 40%-99%, 5 occlusions, and 3 intercostal steals were detected. These results, compared with selective angiography, showed high sensitivity, specific ity, and accuracy of echo-Doppler of the IMAg.