Background: Following the Intraaortic Balloon Pump in Cardiogenic Shock II (IABP-SHOCK II) trial, intra-aortic balloon pump (IABP) was largely abandoned in southeastern Denmark and the use of Impella CP increased in patients with acute MI and cardiogenic shock (AMICS), creating two distinct time eras.
Hypothesis: Early use of Impella CP is associated with improved 30-day mortality in patients with AMICS, and early use of IABP is not.
Methods: We identified all patients with AMICS in southeastern Denmark in 2010–2017 by individual review of medical records. We included patients diagnosed with shock in the cardiac catheterisation laboratory receiving percutaneous coronary intervention (PCI) ≤24 hours of symptom onset and intensive care treatment. Early use of Impella CP/IABP was defined as device deployed before PCI if shock manifested before PCI, or as device deployed immediately after PCI if shock developed during PCI. Patients receiving early Impella CP/IABP were matched 1:1 to their nearest neighbour control from the same time era, according to a propensity score based on age, left ventricular ejection fraction (LVEF), lactate, estimated glomerular filtration rate and cardiac arrest before arrival to the cardiac catheterisation laboratory.
Results: We identified 40 patients receiving early Impella CP and 40 patients receiving early IABP. Patients receiving early Impella CP had median LVEF 15% (interquartile range [IQR] 10; 25) and median lactate 8.5 mmol/l (IQR 4.5; 11.7). Patients receiving early IABP had median LVEF 30% (IQR 20; 40) and median lactate 3.5 mmol/l (IQR 1.8; 5.7). Early Impella CP was associated with improved 30-day mortality versus the control group, corresponding to a number needed to treat of three (30-day mortality 40.0% versus 77.5%, p<0.001). Although numerically fewer patients died in the early IABP versus control group, the difference was not statistically significant (30-day mortality 27.5% versus 37.5%, p=0.35).
Conclusion: In patients with AMICS, early use of Impella CP was associated with improved 30-day mortality compared to a matched control group. Early use of IABP was not associated with improved outcome.