Off-pump coronary artery bypass grafting reduces mortality and stroke in patients with atheromatous aortas: A case control study

Background - Patients with severe atheromatous aortic disease (AAD) who undergo coronary artery bypass (CABG) have an increased risk of death and stroke. We hypothesized that in these high risk patients, off-pump coronary artery bypass (OPCAB) technique is associated with lower morbidity and mortality. Methods and Results - Between June 1993 and January 2002, 5737 patients undergoing CABG had routine intra-operative TEE with 913 (15.9%) found to have severe AAD in the aortic arch or ascending aorta. Of these, 211 patients who underwent OPCAB were matched with 211 on-pump CABG patients by age, ejection fraction, history of stroke, cerebrovascular disease, diabetes, renal disease, nonelective operation, and previous cardiac surgery. Hospital mortality was 11.4% (24/211) for on-pump CABG and 3.8% (8/211) for OPCAB ( P = 0.003). Multivariate analysis revealed that increased mortality was associated with on-pump CABG ( P = 0.001), acute MI ( P = 0.03), number of grafts ( P = 0.01), age ( P = 0.01), history of stroke or cerebrovascular disease ( P = 0.04), CHF ( P = 0.02), and peripheral vascular disease ( P = 0.03). Multivariate analysis showed that OPCAB technique was associated with decreased stroke ( P = 0.05). Freedom from any complication was 78.7% for on-pump CABG and 91.9% for OPCAB ( P < 0.001). At 36 month follow-up multivariate analysis revealed that increased mortality was associated with age ( P = 0.001), previous MI ( P = 0.03), and renal disease ( P = 0.04), whereas increased survival was associated with increased number of grafts ( P = 0.001) and OPCAB ( P = 0.01). Conclusions - OPCAB surgery in patients with severe AAD is associated with lower risk of death, stroke and complications and improved mid-term survival. Routine intra-operative TEE allows identification of these patients and directs choice of appropriate surgical technique.