Altshock-2 Trial
Details
Altshock-2 randomised patients with acute decompensated heart failure complicated by cardiogenic shock (HF-CS) to early intra-aortic balloon pump (IABP) versus standard care. It is one of the few randomised device trials conducted specifically in the HF-CS phenotype, rather than in AMI-CS. (sources/cardiogenic-shock-nejm-2026, rating: very high)
Key Facts
- n = 101, randomised; HF-CS. (sources/cardiogenic-shock-nejm-2026, rating: very high)
- Early IABP did not improve survival or bridge to heart replacement therapy at 60 days. (sources/cardiogenic-shock-nejm-2026, rating: very high)
- The result is consistent with IABP-SHOCK II in AMI-CS, extending the null finding to the HF-CS phenotype. (sources/cardiogenic-shock-nejm-2026, rating: very high)
- HF-CS has no positive randomised device trial: this is the evidence void against which the positive DanGer Shock result (STEMI-CS only) must be read. (sources/cardiogenic-shock-nejm-2026, rating: very high)
Contradictions / Open Questions
- The trial is small (n=101) and powered for a composite of survival and bridge to transplant, so it cannot exclude a modest benefit; it establishes absence of a large effect, not equivalence. (sources/cardiogenic-shock-nejm-2026, rating: very high)
- The HF-CS phenotype is heterogeneous (acute-on-chronic, de novo, secondary shock), and the trial does not report whether a subgroup benefited. (sources/cardiogenic-shock-nejm-2026, rating: very high)
- Whether a different device (microaxial pump, VA-ECMO) helps HF-CS is untested; current guidance limits MCS to patients with a chance of myocardial recovery or eligibility for durable LVAD/transplant. (sources/cardiogenic-shock-nejm-2026, rating: very high)
Connections
- Related to concepts/Cardiogenic-Shock — HF-CS phenotype and the trial-evidence gap
- Related to concepts/Cardiogenic-Shock — IABP in HF-CS and device selection
- Related to entities/IABP-SHOCK-II-Trial — the AMI-CS counterpart with the same null result
- Related to entities/Heart-Failure — the underlying population