Predicting fast recovery in infarct related cardiogenic shock: insights from the DanGer Shock trial

The DanGer Shock trial demonstrated a mortality benefit with routine use of a microaxial flow pump (mAFP) in ST-elevation acute myocardial infarction complicated by cardiogenic shock (STEMI-CS), but at a cost of more complications.1 Routine use of a mAFP may, however, expose some patients to unnecessary risk, underscoring the need to identify those who stabilize rapidly and are less likely to benefit from device therapy.

This post hoc exploratory analysis of the DanGer Shock trial, which randomized STEMI-CS patients to mAFP plus standard care (SoC) or SoC alone, defined "Fast Recovery" as cardiac intensive care unit (CICU) discharge alive within 3 days of randomization. "Fast Recovery" predictors in the SoC arm were identified using a data-driven logistic regression framework based on baseline variables available at catheterization lab admission, with model robustness assessed through extensive bootstrap validation.

Among 355 patients (SoC 176; mAFP 179), "Fast Recovery" occurred in 29% of the SoC group vs. 15% of the mAFP group. Early CICU discharge favored SoC through day 3 (HR 2.27, 95% CI 1.48–3.49), with no difference thereafter. Median CICU stay beyond day 3 was 13 days (SoC) vs. 12 days (mAFP), and 94 deaths occurred by day 3 (29% SoC; 24% mAFP).

Compared with patients with longer CICU stays, "Fast Recovery" patients required less inotropic support (44% vs. 85%) and mechanical ventilation (35% vs. 82%), with only one needing ECMO. Their 180-day mortality was markedly lower (9% vs. 46%, P<0.001) and similar between treatment arms (P=0.41).

In the SoC arm, "Fast Recovery" was associated with lower age (OR 0.65 per 10 years; P=0.017), higher LVEF (OR 1.88 per 10 points; P<0.001), lower heart rate (OR 0.82 per 10 bpm; P=0.019), lower lactate (OR 0.39 per doubling; P=0.004), and higher glucose (OR 1.07 per mmol/L; P=0.056). Resuscitated patients showed a non-significant trend toward faster recovery (OR 2.08; P=0.11). Model discrimination was modest (AUROC optimism-corrected 0.74).

The DanGer Shock trial showed a survival benefit of mAFP use in STEMI-CS, yet about one-third of SoC patients experienced rapid hemodynamic recovery. These "Fast Recovery" patients were characterized by higher LVEF, younger age, and lower lactate, but individual prediction accuracy remained modest. While mAFP offers benefits overall, distinguishing patients who will recover rapidly without it remains challenging and warrants further investigation.