Intra-Aortic Balloon Pump in Heart Failure–Related Cardiogenic Shock: A Meta-Analysis of Randomized Clinical Trials

Pathophysiologic assumptions and clinical data frame a promising role for intra-aortic balloon pump (IABP) in heart failure-related cardiogenic shock (HF-CS). Currently, two randomized clinical trials (RCT) exploring this hypothesis have been published, yielding inconclusive results. We thus designed this meta-analysis to assess the efficacy of IABP in HF-CS. Randomized clinical trials comparing IABP to standard of care (SoC) in patients with HF-CS were included. The study endpoint was survival or successful bridge to heart replacement therapies (HRT) at 60 days. Meta-analytic results are presented as risk difference (RD) and odds ratio (OR). Two RCTs were included (IABP group: 69 patients; SoC group: 64 patients). Patients were in Society for Cardiovascular Angiography & Interventions (SCAI) CS stage B in 21.1% and in stages C/D in 78.9%. Intra-aortic balloon pump use was associated with a nonsignificant trend for better 60 day survival or successful bridge to HRT with moderate heterogeneity between studies (RD: 0.12; 95% confidence interval [CI]:-0.02 to 0.27; p = 0.096; I2 = 49%; OR: 1.94; 95% CI: 0.87-4.32). Subgroup testing demonstrated a significantly improved 60 day survival or successful bridge to HRT with IABP in the SCAI C/D cohort with low heterogeneity (RD: 0.17; 95% CI: 0.01-0.34; p = 0.040; I2 = 14%; OR: 2.52; 95% CI: 1.02-6.23), but not in the SCAI B cohort (RD: 0.06; 95% CI: -0.36 to 0.24; p = 0.712; I2 = 0%; OR: 0.72; 95% CI: 0.13-4.01). This meta-analysis of RCTs supports the clinical utility of IABP in patients with HF-CS with SCAI C/D CS stages. These findings highlight the need for future randomized trials, designed with enrollment criteria based on clinical and hemodynamic features associated with potential responsiveness to IABP support.