Different behavior of sequential versus single left internal mammary artery to left anterior descending area grafts(1).

To study echo Doppler characteristics of sequential versus single left internal mammary artery (LIMA) to left anterior descending (LAD) area grafts transthoracic echo Doppler at the LIMA origin and angiography were performed pre- and postoperatively. In 17 patients single LIMA to LAD (group I) and in 45 patients sequential LIMA to LAD area (group II) bypass grafting was performed. All patients show an early postoperative shift towards diastolic coronary Doppler velocity spectra. Only group II shows a further significant late increase in diastolic, velocity time integral and some systolic echo Doppler parameters at rest. Diastolic peak and diastolic as well as total mean and velocity time integral maximal values are significantly higher in group II in late postoperative hyperemic response. Preoperative and late control angiography showed no significant differences in overall grading of native LAD stenosis between both groups. The large coronary reserve in LIMA sequential grafts may contribute to an improved long-term patency.