Comparison of Outcomes for Off-Pump Versus On-Pump Coronary Artery Bypass Grafting in Low-Volume and High-Volume Centers and by Low-Volume and High-Volume Surgeons

Abstract

In terms of in-hospital outcomes, controversy still remains whether off-pump coronary artery bypass grafting is superior to on-pump coronary artery bypass surgery. We investigated whether the volume of off-pump coronary artery bypass procedures by hospital and individual surgeon influences patient outcomes when compared with on-pump coronary artery bypass surgery. Discharge records from the Nationwide Inpatient Sample were retrospectively reviewed for in-hospital admissions from 2003 to 2011, including 999 hospitals in 44 states. A total of 2,094,094 patients undergoing on- and off-pump coronary artery bypass surgery were included. In patients requiring 2 or more grafts, off-pump coronary artery bypass compared with on-pump coronary artery bypass was associated with increased risk-adjusted mortality when performed in low-volume centers (<29 cases per year) (odds ratio [OR] 1.32, 95% confidence interval [CI] 1.06 to 1.57) or by low-volume surgeons (<19 cases per year) (OR 1.26, 95% CI 1.02 to 1.56). In high-volume off-pump coronary artery bypass centers (≥164 cases per year) and surgeons (≥48 cases per year), off-pump coronary artery bypass reduced mortality compared with on-pump coronary artery bypass in cases requiring a single graft (OR 0.66, 95% CI 0.49 to 0.89 and OR 0.33, 95% CI 0.22 to 0.47, respectively) or 2 or more grafts (OR 0.82, 95% CI 0.66 to 0.99 and OR 0.63, 95% CI 0.49 to 0.81, respectively). In conclusion, the outcome of off-pump coronary artery bypass grafting procedures is dependent on volume at both the institution and the individual surgeon level. Off-pump coronary artery bypass should not be performed at low-volume centers and by low-volume surgeons.

On- or Off-pump Coronary Artery Bypass Surgery. Is the Debate Settling Down?

“…Conversely, in high-volume OPCAB centers (≥ 164 cases/year) and surgeons (≥ 48 cases/year), OPCAB reduced mortality compared with on-pump CABG in cases requiring a single graft or two or more grafts. Therefore, OPCAB outcome is dependent on volume at both the institution and the individual surgeon levels and should not be performed at low-volume centers and by low-volume surgeons [9] .…”

Cirurgia de revascularização do miocárdio com e sem circulação extracorpórea. O que os novos estudos evidenciam?

“…Um estudo realizado por Benedetto et al (16), envolvendo 999 centros de cirurgia cardíaca e um total de 2.094.094 pacientes, comparou os resultados de CRM com e sem CEC procurando evidenciar diferenças nos desfechos dos procedimentos realizados por cirurgiões que possuíam uma maior experiência no procedimento sem bomba versus cirurgiões que eram menos experientes nessa técnica, bem como os resultados de centros que realizavam com maior e menor frequência o procedimento sem CEC. O grupo concluiu que, para procedimentos sem CEC, os resultados são claramente dependentes do volume cirúrgico, tanto do centro de cirurgia cardíaca como do cirurgião individual (14). Esse estudo é de grande relevância, pois infere que, os resultados pós-operatórios da CRM sem CEC estão intimamente relacionados com a acurácia do cirurgião, sendo que serão positivos, se realizados por uma equipe experimente neste procedimento.…”

Myocardial surgical revascularization as a subspecialty: to be or not to be, that is the question

“…Another potential advantage of using multiple arterial grafts is the possibility to perform off-pump CABG (OPCABG) without manipulation of the ascending aorta (an-aortic OPCABG). This has been shown to reduce the risk of stroke by 78% when compared to conventional on-pump CABG [34] . However, this is arguably the most technically challenging variant of CABG and an analysis of registry data from the US showed that OPCABG has better in-hospital results compared to on-pump surgery for large volume centers and surgeons but worse outcomes when compared to conventional on-pump CABG in low volume settings [35] .…”