Incomplete revascularization during OPCAB surgery is associated with reduced mid-term event-free survival

Background. The aim of this study was to compare early and mid-term outcome in patients undergoing off-pump coronary artery bypass surgery who have had complete revascularizations and incomplete revascularizations (IRs). Methods. Patient and operative data were collected prospectively for all patients who had off-pump coronary artery bypass surgery. Patients with multivessel disease were classified as having IR if the number of diseased coronary systems (left anterior descending coronary artery, circumflex and right coronary artery) exceeded the number of distal anastomoses. In-hospital outcomes, survival, and event-free survival were compared between patients with complete revascularization and IR using propensity scores to take account of differences in prognostic factors. Results. There were 1,479 off-pump coronary artery bypass surgery patients between April 1996 and December 2002 (30% of all coronary artery bypass graft patients), and 16.0% (237 patients) had IRs. Patients with IRs tended to be older and were female, had more extensive disease, worse dyspnea, a higher Parsonnet score, poorer ejection fraction, congestive cardiac failure, asthma or chronic obstructive airways disease, and previous cardiac surgery. The adjusted hazard ratio for patient survival with IRs versus complete revascularizations was 1.56 (95% confidence interval, 1.19 to 2.06; p = 0.001). Analyses for multiple time periods confirmed that IRs had a significantly increased risk of death, but also that the risk disappeared after the first 4 to 6 months of follow-up (P < 0.0001). Conclusions. Compared with off-pump coronary artery bypass surgery patients with complete revascularizations, those with IRs have reduced survival but only in the first 4 to 6 months after surgery. Patients' preoperative condition, rather than IR itself, may explain these findings because IRs should have mid-term as well as early effects.