Bilateral internal mammary artery for coronary revascularization. Early experience of 100 cases

One hundred cases are presented in which both right and left internal mammary artery (IMA) were used as coronary bypass grafts. Special indications were thrombosis of previous venous graft (14 cases), poor venous resources (10) and small-vessel (probe less than 1.5 mm) disease (34), but bilateral IMA was used also for routine revascularization (42 cases). The total 212 distal IMA anastomoses included 12 jump grafts, three free grafts and seven thrombendarterectomies. There were 3.8 distal anastomoses per patient, 2.1 with IMA and 1.7 with vein graft. The right IMA was preferably inserted into LAD and the left into diagonal or obtuse marginal coronary artery. Excessive postoperative bleeding was the only major complication attributable to bilateral IMA grafting in the 97 survivors of surgery. In routine revascularization the procedure involved minimal morbidity and no mortality. The superiority of the IMA as regards long-term patency is widely recognized. Since many thrombosed vein grafts will require replacement, we believe that bilateral IMA grafting will become common, and it is also an option when no suitable vein is available.