A Comparison Of Off-and On-pump Coronary Artery Bypass Surgery On Long-term Major Adverse Cardiovascular And Cerebrovascular Events

Objectives:Coronary artery bypass surgery(CABG)is an effective way to cure coronary atherosclerotic heart disease.The initial operation was on-pump coronary artery bypass surgery(CCABG).Recently,the complications brought with cardiopulmonary bypass and cardioplegic arrest have attracted more and more attention.With the prevalence of minimally invasive surgery,off-pump coronary artery bypass surgery(OPCAB)is gradually accepted by the public as a new trend.OPCAB has the advantages of less resource demand and surgical trauma as well as ease of operation,but the high tech and difficulty mean high level of the surgeon.Although it is considered that OPCAB can reduce postoperative complications,the long-term prognosis is still unclear.This study aimed to determine the comparison of long-term MACCE between the two surgical methods.Methods:This study was designed as a prospective study.From May 23,2007 to October 17,2011,we collected the baseline and perioperative data of 349 patients who underwent first-time elective coronary bypass surgery in Fuwai Hospital and joined the global multi-center study "CORONARY(The CABG Off or On Pump Revascularization Study)".174 patients in CCABG group and 175 in OPCAB group.Patients scheduled to participate in the study if they had one or more of the following risk factors:(1)70 years old or more;(2)peripheral arterial disease,cerebrovascular disease,or more than 70%of carotid stenosis;(3)renal insufficiency.(4)Patients between 60 to 69 years were also eligible if they suffered one or more of the following risk factors:①suffering with diabetes(requiring an oral hypoglycemic agent,insulin,or both);② urgent revascularization(after an acute coronary syndrome);③a left ventricular ejection fraction less than 35%;④a recent history of smoking(<1 year before the study).Patients were excluded for the following reasons:(1)planned valve surgery(2)any contraindication to CABG(3)a decision by a surgeon that one of the two techniques was not feasible for that patient(4)a life expectancy of less than 2 years(5)emergency or repeat CABG surgery.The primary endpoint of this study was to compare the long-term MACCE rates,defined as cardiac related or sudden death,MI,the need for repeat revascularization,and stroke between ONCABG and OPCAB.The continuous variables of the baseline were compared by Student t tests,categorical variables usingχ2tests.The time to the first occurrence of any one of the primary outcomes was described with Kaplan-Meier survival curves,and the comparisons between the two groups were performed by means of a log-rank test.Results:The average follow-up is 85 months(rank from 64 to 117 months)with 1.7%miss rate.The baseline of the two groups has statistical homogeneity in age(65.8 ± 4.7:65.5±4.8,P=0.458),male(78.7%:78.3%,P=0.919)and ejective fraction(61.8±6.6%:62.7±6.8%,P=0.179)etc.In terms to perioperative data,the number of distal anastomoses(3.53±0.67:3.46±0.75,P=0.162)and the usage of LIMA(92.5%:96%,P=0.163)has no significant difference between the two groups.The incidence rate of the perioperative complications has no significance between the two groups.Kaplan-Meier analysis of freedom from MACCE(HR=1.298,95%CI:0.817-2.061,P=0.27 by the log-rank test)and mortality(HR=1.135,95%CI:0.648-1.990,P=0.658 by the log-rank test)reveals no significant difference between the two groups.Horizontal comparison of the patients separated by SinoSCORE reveals no significant difference between the two groups.The patients on the same strategy with different risk levels have no statistics difference in MACCE.By analyzing the graft image of 490 grafts of 75 and 66 patients in OPCAB and ONCABG respectively,we find the two groups have similar grafts patency rate(P>0.05)despise of different distal anastomosis and graft source.We divide the patients into three ranks:no grafts with stenosis,one graft with stenosis,two or more grafts with stenosis,every rank has similar rate between OPCAB and ONCABG groups.Conclusions:OPCAB did not provide better perioperative results and long-term MACCE-free survival compared with ONCABG.Patients with different SinoSCORE risk levels have similar outcomes in two operation strategy.The long-term graft patency rate has no significant difference between the two groups.