Elective Intra-Aortic Balloon Pump and Survival in High-Risk Percutaneous Coronary Intervention

Background: The optimal mechanical circulatory support strategy for patients undergoing high-risk percutaneous coronary intervention (PCI) remains uncertain. Randomized trials evaluating elective intra-aortic balloon pump (IABP), Impella, and standard care have reported conflicting results and have not been synthesized within a unified comparative framework. Research Question/Hypothesis: We evaluated the comparative efficacy and safety of elective IABP, Impella, and standard care in planned high-risk PCI. Methods: We systematically identified randomized controlled trials enrolling patients with severe left ventricular dysfunction undergoing planned high-risk PCI. A Bayesian random-effects network meta-analysis compared elective IABP, Impella, and standard care. The primary outcome was all-cause mortality. Secondary outcomes included periprocedural myocardial injury, major bleeding, vascular complications, spontaneous myocardial infarction, and stroke. Results: Three randomized trials (BCIS-1, PROTECT II, and CHIP-BCIS3) comprising 1,053 patients formed a closed triangular evidence network. Model convergence was excellent (all R̂<1.01), with low estimated between-study heterogeneity (posterior median τ=0.346). For all-cause mortality, elective IABP demonstrated the most favorable treatment profile. Compared with standard care, IABP was associated with a 40% reduction in mortality odds (OR 0.60, 95% CrI 0.24-1.31) and an 89.7% posterior probability of benefit. This signal remained consistent across prespecified sensitivity analyses, including long-term follow-up data (OR 0.64, 95% CrI 0.29-1.30; probability of benefit 91.4%). Impella was associated with a directionally unfavorable mortality profile compared with standard care (OR 1.14, 95% CrI 0.47-2.24), with a 63.7% posterior probability of harm. Indirect comparison between Impella and IABP demonstrated an OR of 1.88 (95% CrI 0.69-5.06), with a 91.5% posterior probability that Impella was associated with higher mortality than IABP. Treatment ranking strongly favored IABP. IABP had an 85.1% probability of being the optimal strategy for survival (SUCRA 0.906), compared with 8.0% for standard care (SUCRA 0.370) and 6.9% for Impella (SUCRA 0.224). Rankings remained stable across sensitivity analyses. No significant differences were observed for secondary outcomes, although event rates were low and certainty of evidence was limited. Conclusions: Among randomized trials of mechanical circulatory support during high-risk PCI, elective IABP demonstrated the highest probability of survival benefit and consistently ranked as the preferred strategy. Impella did not demonstrate a mortality advantage and showed a directional signal toward increased mortality compared with IABP and standard care. These findings highlight the need for adequately powered head-to-head randomized trials.