Objective: An increasing number of patients undergoing heart surgery have had a prior coronary stent placement. This study was designed to examine the effect of this situation on the mid-term outcomes of off-pump coronary artery bypass graft (OP-CABG) surgery.
Methods: A comparative retrospective non-randomized comparison was performed as follows: all patients undergoing OP-CABG from January 2005 to December 2009 at our centre were divided into two groups: those who did or did not have stents at the time of surgery. We compared the incidences of the following events: (i) death and (ii) combined major adverse cardiac events (MACEs): death, myocardial infarction (MI) and repeat revascularization. Cox's proportional hazards analysis adjusted by a propensity score (n:m) were performed to determine the effects of prior stent placement on the risks of such events.
Results: A total of 1020 patients were included, of which 156 (15.6%) had at least one stent. The median follow-up was 32.32 months (interquartile rank 18.08-48). The overall 1, 3 and 5-year survival rates were 95, 92 and 91% for the without-stent group vs. 82, 77 and 74% for the with-stent group, respectively. The 1, 3 and 5-year survival rates free from MACEs were: 92, 87 and 76% for patients without stent vs. 77, 66 and 56% for those with stents. Patients with stent showed an increased risk of death [hazard ratio (HR) 3.631, 95% confidence interval (CI) 2.29-5.756] and MACEs (HR 2.784, 95% CI 1.962-3.951). When adjusted by the propensity score, prior stent placement continued to increase the risks of death (HR 3.795, 95% CI 2.319-6.21) and MACEs (HR 2.89, 95% CI 2.008-4.158).
Conclusions: Patients with intracoronary stents have a lower survival rate and a greater risk of death, MI or need for repeat revascularization during the mid-term follow-up after OP-CABG.