Analysis Of Mortality Risk Factors Following Isolated Off-pump Coronary Artery Bypass And Receiving Of Intra-aortic Balloon Pump

Objective : Intra-aortic balloon pump(IABP)has become the most commonly used circulatory support device in percutaneous coronary interventions(PCI)and all cardiac surgeries due to the advantages it offers,including isolated operation,low price,and relatively low complication rate.At present,studies have shown that renal insufficiency,myocardial infarction within 30 days before surgery,left main stenosis > 50%,emergency surgery and cardiopulmonary bypass time are risk factors for postoperative death in patients with coronary artery bypass grafting(CABG)under assisted by IABP.However,there are currently no clear reports on the risk factors of using an IABP in an off-pump coronary artery bypass(OPCABG).The main objective of this study was to evaluate the risk factors faced by those patients who had accepted off-pump coronary artery bypass grafts and had received IABP treatment intraoperatively or within the 30 days before surgery.The minor objective of this study was to evaluate whether the preventive implantation of IABP before surgery is helpful for the prognosis of patients.Methods: We retrospectively analyzed the general information,preoperative and postoperative laboratory examinations,intraoperative conditions,perioperative drug use of 141 patients.All these patients had received off-pump coronary artery bypass grafting and had an IABP placed,either within 30 days before surgery or during surgery,in the Department of Cardiovascular Surgery at the Affiliated Hospital of Qingdao University from May 2018 to May 2021.The 141 patients were divided into a survival group(124cases)and a death group(17 cases).For the statistical analysis in this study,SPSS26.0 and R language 4.1.0 are used.Cox regression model was used to analyze the risk factors of postoperative death.P<0.05 is considered to be statistically significant.Results: 17 of the 141 patients died(12.1%).Univariate regression analysis showed that left main stenosis(HR=1.23;95%CI,1.11-1.35;p<0.001)、preoperative left ventricular ejection fraction(HR=0.89;95%CI,0.84-0.96;p= 0.001)、postoperative acute kidney injury(HR=5.03;95%CI,1.73-14.64;p=0.03)、number of grafts(HR=0.48;95%CI,0.24-0.94;p=0.033)、age(HR=1.07;95%CI,1-1.14 p= 0.047)were all risk factors that affected the hospital mortality rate.According to the Cox regression model: postoperative acute kidney injury(HR=7.075,95%CI=1.996-25.078,p=0.002)、preoperative left ventricular ejection fraction(HR=0.838,95%CI=0.748-0.938,p=0.002)、left main stenosis(HR=1.215;95%CI,1.074-1.376;p=0.002)、age(HR=1.124;95%CI,1.109-1.241;p= 0.02)all have an impact on patient prognosis.Preventive(within 30 days)and intraoperative implantation of IABP(HR=2.03,95%CI=0.58-7.1,p=0.27)has no impact on patient prognosis.Conclusion:Our analysis shows that postoperative acute kidney injury,preoperative low left ventricular ejection fraction,left main stenosis and age were risk factors for mortality after undergoing isolated off-pump coronary artery bypass and receiving an IABP.Therefore,the occurrence of postoperative acute kidney injury often indicates a poor prognosis.We need to pay close attention to postoperative renal function indicators and actively deal with postoperative renal injury;Elderly patients,especially those over 67 years old,should pay more attention in the process of diagnosis and treatment,and their prognosis is worse than that of younger patients;Once a patient’s left main stenosis exceeds 90%,the prognosis may be significantly reduced;Patients with low preoperative left ventricular ejection fraction have higher postoperative mortality.If conditions permit,we should make adequate preoperative preparation for patients with preoperative cardiac insufficiency;Furthermore,preventive implantation of IABP within 30 days before surgery and intraoperative implantation of IABP had no significant effect on the mortality of patients receiving isolated OPCABG.