VALVE SURGERY COMBINED WITH CORONARY-ARTERY OPERATION - IS THE USE OFINTERNAL MAMMARY ARTERY A PREDICTOR FOR EARLY COMPLICATIONS

The internal mammary artery (IMA) provides better early and long-term patency than venous grafts do. Although IMA is the conduit of choice i n isolated coronary artery bypass grafting (CABG), its use in combined procedures is not routine in some cardiovascular units. During a 16-m onth period, 188 patients underwent valve surgery combined with CABG. Internal mammary grafts were used in 68/188 (36%) patients (group 1) a nd vein grafts without arterial grafts (group 2) in 120/188 (64%). Lef t IMA was implanted in 67/68 (99%) and right IMA in 1/68 (1%) cases. S urgeon A used IMA in 28/44 (64%), surgeon B in 20/32 (63%), surgeon C in 18/44 (41%), surgeon D in 1/4 (25%) and surgeon E in 1/63 (2%) pati ents. The final decision to use IMA in a combined procedure was left u p to the surgeon. Statistically, the preoperative- and perioperative d ata were identical in the two groups, although the frequency of IMA gr afting in patients with double valve replacement and reoperation was l ower (1/68 vs 11/120, ns, and 3/68 vs 9/120, ns). Ten of 188 (5.3%) pa tients died within 30 days after operation. Longer cross-clamp time (P =0.008) and mitral valve replacement (P=0.05) were independent risk fa ctors for early death. The use of IMA did not increase the risk of ear ly mortality. The postoperative variables were similar in the IMA and vein groups, in particular data suggesting perioperative myocardial in farction (CK-MB, catecholamine support). Postoperative mechanical vent ilation was longer in the IMA group, although not significantly (P=0.0 6). Early mortality and morbidity were identical in the two groups in combined procedures. We did not find any hints for an increased risk o f using IMA in this type of surgery. Internal mammary artery implantat ion is safe in selected patients undergoing combined valve and CABG su rgery. Beside the better long-term patency of IMA, its use may have se veral technical advantages.