Background: Despite widespread use, evidence to support preemptive intraaortic balloon pump (IABP) insertion for patients undergoing high-risk coronary artery bypass graft (CABG) surgery remains sparse, and in need of a well-defined clinical trial. To inform the design of a prospective trial, we sought to review outcomes in randomized controlled trials (RCTs) of anticipatory IABP use vs control in patients undergoing high-risk CABG through meta-analysis. The primary endpoint was all-cause mortality within 30 days of surgery. The secondary endpoint was major adverse cardiac and cerebrovascular event (MACCE), a composite of death, myocardial infarction, stroke, or repeat revascularization.
Methods: Using Ovid MEDLINE, we systematically reviewed all RCTs comparing preoperative IABP with control in patients undergoing high-risk CABG, defined as: left ventricular ejection fraction (LVEF) ≤40%, left main stenosis ≥70%, unstable angina, recent myocardial infarction, or prior myocardial revascularization undergoing elective or emergent CABG on or off pump.
Results: Of 950 articles assessed for eligibility, 10 RCTs of 1261 subjects (mean age, 65.0 years; 21.8% women; mean LVEF, 35%) were included. Mortality was significantly lower in patients receiving IABP compared with control (relative risk [RR], 0.48; 95% confidence interval [CI], 0.30-0.76; P<.01). The risk of MACCE was also lower with IABP (RR, 0.67; 95% CI, 0.54-0.84; P<.001). No significant differences in major bleeding events (RR, 1.27; 95% CI, 0.44-3.72) or vascular complications (RR, 1.13; 95% CI, 0.42-3.06) were detected.
Conclusions: A strategy of routine prophylactic IABP use may reduce short-term mortality and MACCE in high-risk CABG patients. A definitive, adequately powered, prospective, randomized trial is warranted to confirm these results.