In this propensity-score weighted analysis, LV unloading during VA-ECMO was not associated with improved survival at 60 days, with device-related complications more frequent in the unloading group.
Key Findings
Results
Left ventricular unloading during VA-ECMO was not associated with improved 60-day mortality in patients with refractory cardiogenic shock.
Weighted risk difference for 60-day mortality was 1.4% (95% CI: -11.8%, 14.6%), p = 0.84
264 patients were included (76% male, mean age 53 ± 14 years) from two high-volume ECMO centers between 2019 and 2023
138 patients (52.2%) received VA-ECMO alone and 126 (47.8%) underwent LV unloading
Propensity-score overlap weighting was applied to adjust for baseline differences
2 patients were lost to follow-up
Results
Device-related complications were more frequent in the LV unloading group compared to the VA-ECMO alone group.
Complications were observed across both IABP and Impella unloading strategies
The LV unloading group comprised 78 patients receiving IABP and 48 receiving Impella
No specific complication rates were provided in the abstract, but the difference was noted as a secondary outcome
Results
No significant differences in ECMO weaning rates were observed between patients receiving VA-ECMO alone and those receiving LV unloading.
ECMO weaning rate was a prespecified secondary outcome
The finding applied across both IABP and Impella unloading strategies
The study used a retrospective bi-center design with consecutive patients requiring VA-ECMO for ≥48 hours
Methods
The study used a target trial emulation framework to assess the causal effect of LV unloading strategies in a retrospective observational setting.
Patients were classified as receiving VA-ECMO alone or VA-ECMO with LV unloading if the unloading strategy was applied within 24 hours after ECMO implantation
Data were collected from two high-volume ECMO centers between 2019 and 2023
Propensity-score overlap weighting was the primary method used to adjust for baseline confounding
The primary endpoint was 60-day mortality
Discussion
The authors conclude that a refined, phenotype-driven approach to patient selection for LV unloading in ECMO-supported cardiogenic shock is needed.
Conflicting data exist in the literature regarding the survival benefit of mechanical LV unloading in VA-ECMO patients
The findings are described as 'hypothesis-generating'
Both IABP and Impella were evaluated as unloading strategies, representing different mechanisms and levels of support
The study population had severe refractory cardiogenic shock, with VA-ECMO duration of at least 48 hours required for inclusion
What This Means
This research suggests that adding a device to reduce the workload on the left side of the heart (called 'left ventricular unloading') while a patient is on a heart-lung bypass machine (VA-ECMO) for severe heart failure did not improve survival at 60 days. The study looked at 264 critically ill patients treated at two major hospitals between 2019 and 2023. About half received only the VA-ECMO machine, while the other half also received an additional heart-support device — either an intra-aortic balloon pump (IABP) or a more powerful device called an Impella. After statistically accounting for differences between patient groups, there was no meaningful difference in survival outcomes between those who did and did not receive the additional unloading device.
Notably, patients who received the additional unloading devices experienced more device-related complications, without any clear benefit in terms of survival or being successfully weaned off the ECMO machine. This raises questions about whether the routine or non-selective use of these additional devices is beneficial for all patients in this situation.
This research matters because the use of combined mechanical heart support devices is increasing in intensive care units, and their costs and risks are substantial. These findings suggest that not all patients on VA-ECMO may benefit equally from additional heart unloading devices, and that future research should focus on identifying specific patient characteristics — or 'phenotypes' — that predict who might actually benefit. The authors emphasize that these are hypothesis-generating findings and that randomized controlled trials targeting specific patient subgroups are needed to clarify this important clinical question.
Dettling A, Saura O, Dilange L, Levy D, Lucenteforte M, Beer B, et al.. (2026). Left ventricular unloading during VA-ECMO for refractory cardiogenic shock: a target trial emulation multicenter analysis.. Critical care (London, England). https://doi.org/10.1186/s13054-026-06213-4