Tailoring Operations to the Patient Is Always Best
Authors: Faisal G. Bakaeen, Joseph F. Sabik
Journal: Circulation (2016)

n this issue of Circulation, Kirmani and colleagues 1 report the early and late outcomes of >13 000 patients who underwent either on-or off-pump coronary artery bypass grafting (CABG) at a single institution from 2001 to 2015.They found that after propensity matching, these procedures resulted in similar long-term survival and freedom from all-cause mortality and coronary reintervention.However, off-pump surgery patients had shorter hospital stays and fewer perioperative complications, such as myocardial infarction.The authors are to be congratulated on their excellent observational study and clinical outcomes.During the study, overall hospital mortality after CABG was 2%, stroke <1%, and mediastinitis 0.2%.In addition, the prevalence of conversions from off-to on-pump CABG was only 1.6%.This compares favorably to the 3% prevalence reported in the Society of Thoracic Surgeons Adult Cardiac Surgery Database. 2These excellent clinical outcomes and few conversions are a testament to the fine skill and vast experience of the surgical teams involved in this study.However, before we conclude from this study that off-pump CABG is as good, if not better, than on-pump CABG, it is important to review the study's strengths and weaknesses, as well as, others' findings.This report is an observational study; despite propensity matching, it appears to have important confounders.Surgeons in the study preferred almost exclusively on-or off-pump CABG.The authors point out that, among the 17 surgeons, there was a bimodal distribution in preference with regard to operative technique.There is no way to adjust for surgical ability, and it is possible that the better results observed with off-pump surgery were due not to the actual surgical technique but surgeon ability.In addition, off-pump surgeons were more likely to use arterial grafts than those preferring on-pump surgery; ≈50% of the off-pump CABG patients received a radial artery graft, in contrast to only 15% of the on-pump patients.This finding was similar in the propensity-matched groups and is of particular importance because evidence shows that arterial grafts improve the outcomes of CABG.The study spans 14 years; incorporating the date of surgery as a covariate and adjusting for secular trends are notably missing from the analysis.Although this study has limitations, it serves as further evidence that off-pump CABG can be associated with excellent outcomes when performed by experienced surgeons. 3,4 Multicenter observational data suggest that programs with greater offpump CABG experience may have better results than programs that perform this procedure less frequently. 5 How do the findings of this study compare with recent multicenter randomized studies?Two recent, well-designed, expert-based randomized trials-the CORO-NARY trial (CABG Off or On Pump Revascularization) 6 and the GOCABE trial (German Off-Pump Coronary Artery Bypass Grafting in Elderly Patients) 7 -did not find better outcomes with off-pump CABG compared with on-pump CABG regarding the primary tailoring operations to the Patient is always Best