BILATERAL INTERNAL MAMMARY ARTERY GRAFTING IN WOMEN - A 21-YEAR EXPERIENCE

Background. Coronary artery bypass grafting traditionally has carried a higher mortality rate in women than in men. It remains the leading c ause of death in women despite major advances in diagnosis and treatme nt over the past 2 decades. Methods. A retrospective analysis was cond ucted to identify risk factors that adversely influence hospital morta lity, morbidity, and long-term clinical results in women undergoing bi lateral internal mammary artery grafting. From January 1972 through Oc tober 1994, 327 consecutive women received bilateral internal mammary artery grafts and supplemental vein grafts. Patient age ranged from 32 to 84 years (mean, 65.7 years). There were 262 patients (80.1%) with three-vessel disease; 71 (21.7%) had substantial (>50%) stenosis of th e left main coronary artery, 65 (19.9%) had a moderately reduced (0.30 to 0.50) ejection fraction, and 11 (3.4%) had a severely reduced (<0. 30) ejection fraction. Preoperatively, 316 patients (96.6%) were in Ne w York Heart Association class III or IV. Results. There were 1,016 co ronary artery grafts (mean, 3.1 per patient). The overall hospital mor tality rate was 3.4% (11 of 327). Postoperative complications included myocardial infarction in 18 patients (5.5%), stroke in 5 (1.5%), pulm onary insufficiency in 11 (3.4%), reoperation for bleeding in 7 (2.1%) , and sternal infection in 8 (2.4%). Independent predictors of operati ve death were postoperative cardiac arrest (p < 0.001), use of intraao rtic balloon pump (p < 0.001), and reoperation for bleeding (p < 0.050 ). Follow-up was completed on 316 hospital survivors (100%) and ranged from 6 months to 21 years (mean, 5.1 years). Actuarial survival (mean +/- standard error of the mean) was 90.5% +/- 1.9% at 5 years and 65. 6% +/- 6.1% at 10 years. At follow-up, 252 patients (94.0%) were asymp tomatic in New York Heart Association class I, and 12 (4.5%) were in c lass II. Conclusions. This longitudinal study demonstrates that bilate ral internal mammary artery grafting, though technically demanding, ca n be achieved in women with low hospital mortality and morbidity rates . Patients experienced reduced late cardiac events, excellent function al improvement, and enhanced long-term survival.