Circulatory support with larger volume intra-aortic balloon pump vs. standard volume or no-balloon pump during high-risk percutaneous coronary interventions. A randomised study

Introduction
Percutaneous coronary intervention in high-risk patients (HRPCI) is associated with increased risk of periprocedural complications such as hypotension and shock. Mechanical circulatory support devices may the bridge patient safely throughout the procedure and are often used in this setting.

Aim
We assessed the outcomes of patients subjected to HRPCI and supported with intra-aortic balloon pump (IABP) of larger volume (MEGA) compared to standard volume (STRD) or no balloon support at all (CTRL).

Material and methods
In this single-centre, open-label, randomised, controlled trial, HRPCI patients were randomly assigned to three groups: MEGA, STRD, and CTRL in a 1 : 1 : 1 scheme. Screening failure patients were assigned to the registry (REG). Composite haemodynamic endpoint (CHEP) was assessed during the procedure and major adverse cardiac even (MACE)/safety endpoints up to 1-year follow-up (FU).

Results
A total of 36 patients were randomised (13 MEGA, 14 STRD, and 9 CTRL). The incidence of in-hospital MACE was observed in 23.1% of MEGA, 7.1% of STRD and 33.3% of CTRL (p = 0.25) patients; MACE at FU in 50.0%, 35.7%, and 55.6% (p = 0.61); major bleeding in 46.2%, 28.6%, and 22.2%, (p = 0.45); and CHEP in 15.4%, 50.0%, and 44.4%, respectively (p = 0.13). On per-treatment (PT) analysis (16 MEGA, 10 STRD, and 21 CTRL), including 11 patients from REG, in-hospital MACE was observed in 18.8% of MEGA, 10.0% of STRD, and 23.8% of CTRL (p = 0.64) patients; MACE at FU in 53.3%, 20.0%, and 57.1% (p = 0.12); major bleeding in 37.5%, 20.0%, and 33.3% (p = 0.62); and CHEP in 15.5%, 50.0%, and 52.4%, respectively (p = 0.023).

Conclusions
Larger volume intra-aortic balloon pump might be effective at reducing haemodynamic instability during HRPCI without a statistically significant effect on safety endpoints or MACE.