Key Points:
- Cardiogenic shock (CS) mortality remains high despite increased utilization of mechanical circulatory support. Specifically, no randomized data has supported the use of Impella CP in CS.
- In DanGer Shock, routine use of Impella CP was compared with standard of care in selected individuals with cardiogenic shock after STEMI.
- Impella CP use was associated with a 13% reduction in 6-month all-cause-mortality but increased rates of both ischemic and hemorrhagic adverse events.
Cardiogenic shock mortality remains unacceptably high and has stalled over the past decade despite increased utilization of mechanical circulatory support (MCS). The micro axial flow pump Impella CP is used frequently in acute MI-related cardiogenic shock (AMI-CS), but Impella use has never been demonstrated to result in decreased CS mortality in randomized trials. In a breaking presentation at the 2024 ACC conference today, Dr. Jacob Moller (Odense University Hospital, Denmark) and his team presented their study: “DanGer-Shock: Percutaneous Transvalvular Micro-axial Flow Pump in Infarct Related Cardiogenic Shock.”
The DanGer Shock trial (NCT01633502) was an international, multicenter, randomized trial examining Impella CP vs standard of care in AMI-CS. Participants were required to have STEMI, evidence of hypotension (sBP <100 mm Hg) and hypoperfusion (lactate ≥2.5 mmol/L), and LVEF <45%. Key exclusion criteria were comatose out-of-hospital cardiac arrest, RV failure, and mechanical complication of MI. The primary outcome was death from any cause at 180 days. Key secondary outcomes included a) escalation to short- or long-term MCS, heart transplant or death at 180 days and b) days alive out of the hospital at 180 days.
A total of 360 patients were 1:1 randomized to either Impella CP or standard of care at the time of shock diagnosis. The median age was 69 with 21% women; the median time from STEMI to randomization (ie, shock diagnosis) was 4 hours, with 84% of patients being randomized in the cath lab. The median LVEF was 25% and the median baseline lactate was 4.5 mmol/L. Impella CP resulted in a 13% absolute reduction in the primary endpoint of all-cause mortality at 6 months (NNT 8, HR 0.74, 95% CI [0.55-0.99]; p=0.04). Additionally, Impella CP resulted in significantly reduced escalation to MCS, heart-transplant, or death at 180 days (HR 0.72, 95% CI [0.55-0.95]) as well as increased days alive outside of hospital (mean difference 8 days, 95% CI [-9,25]). The effect in the primary endpoint was consistent across MAP subgroups (both > and ≤63 mm Hg); however, individuals with multivessel disease had a signal for greater reduction in all-cause mortality (HR 0.99, 95% CI [0.52-1.87]) compared to those with single-vessel disease (HR 0.68, 95% CI [0.49-0.94]). Adverse events were higher in the Impella arm, with increased moderate or severe bleeding (21.8% vs 11.9%), limb ischemia (5.6% vs 1.1%), renal replacement therapy (41.9% vs 26.7%), and sepsis (11.7% vs 4.5%).
When discussing the clinical implications of the study at the ACC conference, Dr. Moller stated: “The routine use of a mAFP on top of standard care reduced death from any cause in patients with STEMI and cardiogenic shock…this was associated with an increased risk of adverse events…these results cannot be extrapolated to other causes of cardiogenic shock.”
