Life sciences · Journal article

Weekly Journal Scan: Reassessing the promises and challenges of routine left ventricular support during high-risk percutaneous coronary intervention

European Heart Journal · July 21, 2026

Expert Guidance Why this matters to you Expert discussion

A consensus or society position rather than new primary data.

AI Summary

This commentary reviews current evidence on microaxial flow pump support during high-risk PCI, concluding that while observational data (PROTECT III, IMP-IT) suggest benefit through improved revascularization, the neutral REVIVED-BCIS2 trial raises uncertainties about whether PCI itself reduces mortality or heart failure hospitalisation. The 2024 ESC Guidelines assign class IIb (weak) recommendation to the device in carefully selected patients at experienced centres.

What was studied

Journal article. Patients with severe left ventricular dysfunction undergoing complex and high-risk percutaneous coronary intervention with extensive coronary artery disease and limited myocardial reserve..

Key findings

PROTECT II (randomised trial) showed no significant difference in 30-day major adverse events between microaxial flow pump and intra-aortic balloon pump; trial terminated early for futility PROTECT III (single-arm observational) reported more complete revascularisation, less bleeding, and improved 90-day clinical outcomes versus PROTECT II historical cohort IMP-IT registry subanalysis demonstrated association between extent of revascularisation during microaxial flow pump-supported PCI and subsequent survival

Safety

Who this may help

Clinicians should consider microaxial flow pump support selectively in high-risk PCI patients at experienced centres, but recognize that current evidence is mixed: observational data favour complete revascularisation benefits, yet the REVIVED-BCIS2 trial did not confirm mortality or hospitalisation reduction from PCI itself, irrespective of support strategy. The weak (IIb) guideline recommendation reflects this uncertainty.

Plain-language summary

This is a clinical commentary synthesizing evidence on mechanical circulatory support in high-risk PCI, reflecting regulatory guidance and expert interpretation rather than reporting a primary trial result.

Reported figures

Quoted from the source exactly as published.

PROTECT II 30-day major adverse events comparisonno significant difference

Mechanical circulatory support use in REVIVED-BCIS2 PCI arm3%

2024 ESC guideline recommendation classIIb

Clinical bottom line

Caveats

PROTECT III was single-arm and observational, not a randomised controlled trial; comparison to PROTECT II historical cohort introduces bias
REVIVED-BCIS2 used mechanical support in only 3% of the PCI cohort, limiting direct assessment of support benefit
No absolute risk reduction or hazard ratio reported for PROTECT III or IMP-IT outcomes
Commentary does not provide 95% confidence intervals or p-values for benefit estimates across cited trials

Evidence assessment

Graded across the dimensions that decide whether you should act, each from what the source actually supports. There is no single score, and where a dimension was not assessed it says so.

Study design

insufficient

Commentary on multiple trials; no primary design conducted by authors.

Directness

strong

Directly addresses clinical question of LV support during high-risk PCI.

Consistency

limited

PROTECT III and IMP-IT show benefit; REVIVED-BCIS2 was neutral on PCI itself.

Risk of bias

moderate

Mixed evidence includes observational, single-arm, and historical comparisons.

Sample adequacy

insufficient

Commentary synthesizes multiple studies; no single sample size provided.

Source abstract

This comment refers to ‘Left Ventricular Unloading in High-Risk Percutaneous Coronary Intervention’, which was published in the New England Journal of Medicine, https://doi.org/10.1056/NEJMoa2515704. Patients with severe LV dysfunction undergoing complex and high-risk PCI represent one of the most challenging populations in contemporary interventional cardiology.2 Extensive CAD, limited myocardial reserve, and the risk of transient ischaemia during prolonged and technically demanding procedures have provided a compelling rationale for the use of temporary mechanical circulatory support.2 Among available devices, microaxial flow pump has been increasingly adopted to maintain systemic perfusion and unload the LV, with the expectation that improved haemodynamic stability would facilitate more complete revascularization and ultimately translate into LV functional recovery3 and better clinical outcomes.4 The randomized PROTECT II trial, which compared a microaxial flow pump with intra-aortic balloon pump support during high-risk PCI, did not show significant differences in major adverse events at 30 days between the two groups and was terminated early for futility, although a trend towards improved outcomes with microaxial flow pump was observed at a pre-specified 90-day follow-up.5 In the prospective, multicentre, single-arm, observational, FDA-audited post-approval PROTECT III study,6 microaxial flow pump-supported high-risk PCI was associated with more complete revascularization, less bleeding, and improved 90-day clinical outcomes compared to a PROTECT II historical cohort. Likewise, a subanalysis of the IMP-IT registry demonstrated an association between the extent of revascularization achieved during microaxial flow pump-supported PCI and subsequent survival, reinforcing the hypothesis that LV support may derive its benefit by facilitating more complete coronary revascularization.7 However, these data must be interpreted in the context of the neutral findings of REVIVED-BCIS2, where PCI itself failed to reduce death or heart failure hospitalization in patients with severe ischaemic LV dysfunction, independent of the extent of revascularization.8 Of note, mechanical circulatory support was used in only 3% of patients randomized to PCI. Reflecting these uncertainties, the 2024 European Society of Cardiology Guidelines for the management of chronic coronary syndromes assign a class IIb recommendation to the use of microaxial flow pump in carefully selected patients undergoing high-risk PCI in experienced centres.9

Follow from this

Taken from the source record, never inferred. Follow any of these and new work involving them reaches your briefing.

Rocco VergalloD Pedicino