Clinical profile and in-hospital outcome of patients supported by intra-aortic balloon pump in the clinical setting of cardiogenic shock according to aetiology

Despite controversial evidence, intra-aortic balloon pump (IABP) is still the most used temporary mechanical support in cardiogenic shock (CS), as a bridge to recovery or to more advanced mechanical support and/or heart transplantation [1]. Indeed, the available evidence, which is mainly restricted to the context of acute coronary syndromes (ACS) and is limited by the variability of CS definitions, shows no benefit in terms of mortality [2]. Randomized controlled trials on IABP in the setting of non-ACS CS are still missing. As a result, European guidelines do not recommend the routine use of IABP, which may be considered in refractory CS [3].

The aim of our study was to analyse the use of IABP in the context of CS, providing insights into its indications, outcomes, and complications in relation to the aetiology (ACS vs non-ACS) of CS.

We retrospectively enrolled all consecutive adult patients receiving IABP for refractory CS at our tertiary referral Hospital between 2009 and 2018, and analysed data focusing on in-hospital outcomes, including death, recovery, heart transplantation, and escalation to more advanced mechanical support such as venoarterial extracorporeal membrane oxygenation (VA-ECMO) or left ventricular assist device (LVAD), and on IABP-related complications.

403 patients received IABP, 75.2% (n=303) for ACS CS and 24.8% (n=100) for non-ACS CS. With respect to ACS patients, non-ACS patients were younger (age 59±18.3 vs 73.1±12.6 years old, p<0.001), had a lower left ventricular ejection fraction (LVEF) [25% (IR 18–35%) vs 38% (IR 25–45%), p<0.001], were supported by IABP for longer time [6 (IR 2–18) vs 2 (IR 1–4) days, p<0.001], required more use of inotropes/vasoconstrictors [80.0% (n=80) vs 33.8% (n=102), p<0.001], and needed more often escalation to VA-ECMO [23.0% (n=23) vs 1.3% (n=4), p<0.001]. Non-ACS patients showed higher in-hospital mortality than ACS patients [46.0% (n=46) vs 33.9% (n=103), p=0.042]. Non-ACS patients were more frequently bridged to heart transplantation [20.0% (n=20) vs 0.3% (n=1), p<0.001] or LVAD [4.0% (n=4) vs 0.6% (n=2), p=0.055] than ACS patients; mortality after transplantation/LVAD did not significantly differ between the two groups [12.5% (n=3/24) vs 66.7% (n=2/3), p>0.05]. The incidence of IABP-related overall and major complications (including ischemic stroke, major bleeding, and peripheral or visceral ischemia) was not different with respect to the non-ACS vs ACS aetiology [major complications: 8.0% (n=8) vs 5.0% (n=15), p>0.05].

In our experience, in the clinical setting of CS treated with IABP, non-ACS patients show a worse clinical profile and prognosis than ACS patients, and more often require escalation to more advanced mechanical support and/or heart transplantation, while the incidence of IABP-related complications appears similar independently of the aetiology.

Type of funding sources: None.