Does coronary endarterectomy technique affect surgical outcome when combined with coronary artery bypass grafting?

ABSTRACT

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether open coronary endarterectomy (CE) and coronary artery bypass grafting (CABG) compares favourably with closed endarterectomy and CABG in the myocardial revascularization of patients presenting with diffuse coronary artery disease (DCAD). One hundred and fifty-five articles were identified by a systematic search, of which 10 best answered the clinical question incorporating a total of 1203 patients (915 open-CE, 288 closed-CE). All were observational studies. Two were comparative and the remaining eight were case series. The authors, journal, date, country of publication, patient group, study type, relevant outcomes and results were recorded. The open technique involved removal of atheroma under direct vision through an arteriotomy along the length of diffusely stenotic artery, whereas the closed technique involved a smaller arteriotomy and removal via traction on the proximal plaque. The overall postoperative mortality rate associated with open-CE ranged from 2.3 to 10.5%. Both comparative studies demonstrated at least equivalent 30-day mortality between open-CE and closed-CE. Notably, the four studies with highest overall postoperative mortality used a saphenous vein (SV) graft in the majority of patients. Furthermore, two-vessel CE was associated with higher mortality rates. Among these best evidence series, the overall incidence rate of postoperative myocardial infarction (MI) was 7.3% (88/1203). Whether open-CE or the use of internal thoracic artery (ITA) conduit over SV affects postoperative MI rates remains inconclusive. Mid-term and long-term graft patency, and 3-, 4- and 5-year survival rates are all improved when open-CE is combined with the ITA bypass conduit, when compared with closed-CE or open-CE using another conduit. In summary, open-CE with CABG in the setting of DCAD may carry lower 30-day mortality than closed-CE with CABG. Utilization of ITA appears to improve mortality, whereas the SV conduit and multivessel CE may worsen clinical outcome. Furthermore, the ITA may also improve graft patency when combined with open-CE. There is currently insufficient evidence to determine the effect of open-CE on MI incidence. Future large, prospective studies are now required with defined subgroups, stratifying technique, number and territory of the endarterectomy and conduit type in order to determine the patients in whom open-CE may confer the greatest benefit.