Abstract Body (Do not enter title and authors here):
Background The Danish German Cardiogenic Shock trial (DanGer Shock) recently showed a reduction in all-cause mortality when treating selected patients with ST-segment elevation myocardial infarction (STEMI) and cardiogenic shock with a microaxial flow pump (mAFP). Whether there is an age-related differential survival benefit is unknown.

Objective To assess the influence of age on 180-day all-cause mortality in patients with STEMI and cardiogenic shock randomized in DanGer Shock.

Methods In DanGer Shock (an open-label, international, multicenter trial), 355 adult patients (aged ≥18 years with no upper age limit) with STEMI and cardiogenic shock were included and randomized to a mAFP (Impella CP) plus standard care or standard care alone. Patients were stratified in quartiles according to age, and logistic regression analyses were used to assess mortality according to age quartiles, and to evaluate whether age modified the treatment effect of the mAFP.

Results From lowest to highest quartile, patients’ ages ranged from 31-59, 60-69, 70-76, and 77-92, respectively. There were no differences in blood pressure, lactate level, left ventricular ejection fraction and shock severity across age groups. However, the proportion of females (41%) and the prevalence of hypertension (64%) was higher in patients aged ≥77 years (highest quartile), while more patients aged <60 years (lowest quartile) had been resuscitated before randomization.
Mortality increased incrementally from the lowest quartile to the highest (31% vs. 47% vs. 61% vs. 73%, p_log-rank<0.001), with an adjusted odds ratio for death at 180 days of 5.50 (95%CI 2.65-11.8, p<0.001) in the highest quartile compared to the lowest.
Patients in the three lower quartiles had a lower absolute mortality at 180 days if randomized to the mAFP group, whereas patients in the highest quartile had a higher mortality if randomized to the mAFP group, p=0.028 for interaction, Figure.

Conclusion In patients with STEMI-related cardiogenic shock, the overall mortality increased with advancing age, and treatment benefit of the mAFP appeared to diminish in the eldest patients. (DanGer Shock, NCT01633502)