DOI: 10.4244/EIJV15I7A104

Mechanical circulatory support for decompensated heart failure: the last remaining indication for intra-aortic balloon pump?

Jesper Kjaergaard1, MD; Jacob Eifer Møller2, MD; Christian Hassager3, MD

Chronic heart failure (CHF) is associated with risk of volume overload due to progression of the underlying disease or as a result of patient-related causes such as poor compliance with water and salt restrictions, diuretics and other medication regimens. Decompensation episodes are clinically significant as they are related to increased mortality, readmission rates and patient discomfort, even though mortality seems to be decreasing slightly1. One focus for the treatment of acute heart failure is unloading of the heart. While often managed by increasing diuretics, some patients deteriorate and present with low cardiac output failure, which may progress into cardiogenic shock (CS).

While the definition of CS differs between studies and guidelines2, these patients are in grave danger of death and multiorgan failure and must be managed swiftly. While the existing data on diuretic regimens, use of inotropic agents, and level of haemodynamic monitoring are without clear evidence of benefit, and guidelines are relatively imprecise on how to manage these patients, most institutions have developed protocols to manage them with combinations of pharmacological or mechanical circulatory support, and many are improved and stabilised with treatment3.

Mechanical circulatory support may be considered to stabilise the patients in shock2. For more than four decades, the intra-aortic balloon pump (IABP) was used for CS from many causes, including acute myocardial infarction, postoperative heart failure and decompensated CHF.

The efficacy of mechanical circulatory support devices has never been convincingly documented in large prospective randomised trials, with the exception of the IABP-SHOCK II trial by Thiele et al in 20124. This trial showed that, in patients with CS from acute myocardial infarction (AMI) undergoing acute percutaneous coronary intervention (PCI), the use of IABP had no effect on haemodynamics or mortality. Since then, the use of IABP for CS complicating AMI has been abandoned by many institutions5 (Figure 1), which is probably also the case outside the setting of AMI and shock. Other devices that may be applied in this setting include micro-axial pumps, such as the Impella® (Abiomed, Danvers, MA, USA), which is percutaneous and haemodynamically efficient6, but also remains unproven with regard to clinical efficacy. An ongoing large clinical trial is seeking to establish this in patients with AMI7.

Figure 1. Number of cardiogenic shock cases and use of IABP in two tertiary heart centres in Denmark 2010-2017, covering 3.9 million inhabitants. Data adapted from Helgestad et al, 20195.

Decompensated heart failure and cardiogenic shock

CS in the setting of decompensated CHF may differ from CS in relation to AMI in a number of respects. First, the decompensation occurs in a patient who has usually been stable on heart failure medications, including diuretics. Second, in CHF, the heart has remodelled to maintain stroke volume despite a low ejection fraction and the circulation may tolerate increased left atrial (LA) pressure better. Third, the degree of CS and secondary organ failure is often moderate. Fourth, volume overload is almost uniformly severe in CHF, whereas the AMI CS patient is usually euvolaemic.

This fits well with the population included in the trial by den Uil and colleagues reported in this issue of EuroIntervention –Primary intra-aortic balloon support versus inotropes for decompensated heart failure and low output: a randomised trial8.

The authors should be commended for careful selection for the trial of patients who had a failed primary management strategy of escalation of diuretics and volume restriction, and who had deteriorated by developing a state of pre-shock and CS, with low blood pressure, increased filling pressures and signs of low cardiac output and organ dysfunction with low SvO2 as the primary haemodynamic marker. A mean lactate level of 2.0 mmol/l and inclusion within 19-25 hours of hospitalisation suggested that patients were managed swiftly and not allowed to develop prolonged shock before inclusion in the trial.

In the trial, the use of IABP for 48 hours or more was associated with a significantly more favourable effect on several haemodynamic parameters than with a strategy based on inotropes alone (primarily low-dose enoximone): increasing SvO2 after 3 hours, and after 48 hours increasing cardiac power, decreasing NT-proBNP levels, and three times more negative fluid balance. The study was underpowered to show any differences in clinical outcomes, and patients treated with an IABP strategy had a significantly longer length of stay, which may in part be attributed to more frequent use of left ventricular assist devices and heart transplant in these patients.

The authors should be congratulated on performing the trial, not least for the rigorously described inclusion criteria, effectively identifying and randomising patients “sliding” on first-line management of decompensated heart failure.

The trial has several limitations. It was a single-centre trial, the intervention was open label and a significant number of patients had crossover within 48 hours of randomisation, numerically more patients in the IABP group were mechanically ventilated, the primary endpoint was already assessed after 3 hours, and no measures of cardiac output outside the cardiac power calculations are presented. Furthermore, by protocol, the control group received a very low dose of enoximone at the time (3 hours) of the primary endpoint measurement. Nevertheless, the results are intriguing, and could inspire others to perform more, preferably larger-scale trials in this patient population and preferably considering the addition of a strategy based on micro-axial pumps, where data on the efficacy outside of AMI are also sorely needed2.

For the time being, the trial in itself should not change heart failure management guidelines but may underline the need for differentiating the cause of CS and also probably for pursuing the development of management guidelines specifically for these causes of CS.

Conflict of interest statement

J.E. Møller has received a speaker’s fee and research grant from Abiomed. J.E. Møller and C. Hassager are investigators in the DanGer Shock trial. The other author has no conflicts of interest to declare.


References

Volume 15 Number 7
Sep 20, 2019
Volume 15 Number 7
View full issue


Key metrics

Suggested by Cory

10.4244/EIJV13I18A344 Apr 6, 2018
Mechanical circulatory support: the last resort in cardiogenic shock?
Thiele H et al
free

10.4244/EIJV10STA12 Aug 19, 2014
Shock management in acute myocardial infarction
Poss J et al
free

State-of-the-Art Review

10.4244/EIJ-D-20-01296 Aug 27, 2021
Management of cardiogenic shock
Thiele H et al
free

INTERVENTIONAL FLASHLIGHT

10.4244/EIJ-D-17-01109 Sep 20, 2018
Haemodynamic impact of a new pulsatile mechanical circulatory support in high-risk coronary stenting
Bastos M et al
free
Trending articles
151.43

State-of-the-Art

10.4244/EIJ-D-22-00776 Apr 3, 2023
Computed tomographic angiography in coronary artery disease
Serruys PW et al
free
55.9

Clinical research

10.4244/EIJ-D-22-00621 Feb 20, 2023
Long-term changes in coronary physiology after aortic valve replacement
Sabbah M et al
free
54.9

Expert review

10.4244/EIJ-D-21-01010 Jun 24, 2022
Device-related thrombus following left atrial appendage occlusion
Simard T et al
free
43.75

Clinical Research

10.4244/EIJ-D-21-01091 Aug 5, 2022
Lifetime management of patients with symptomatic severe aortic stenosis: a computed tomography simulation study
Medranda G et al
free
39.95

Clinical research

10.4244/EIJ-D-22-00558 Feb 6, 2023
Permanent pacemaker implantation and left bundle branch block with self-expanding valves – a SCOPE 2 subanalysis
Pellegrini C et al
free
X

The Official Journal of EuroPCR and the European Association of Percutaneous Cardiovascular Interventions (EAPCI)

EuroPCR EAPCI
PCR ESC
Impact factor: 7.6
2023 Journal Citation Reports®
Science Edition (Clarivate Analytics, 2024)
Online ISSN 1969-6213 - Print ISSN 1774-024X
© 2005-2024 Europa Group - All rights reserved