DanGer shock criteria and outcomes in acute myocardial infarction-related cardiogenic shock treated with Impella: the J-PVAD registry

The DanGer shock trial showed a survival benefit of Impella in highly selected patients with ST-elevation myocardial infarction-related cardiogenic shock (STEMI-CS). In real-world settings, however, Impella is often used in broader populations not meeting trial criteria. This study aimed to assess the distribution and outcomes of DanGer shock-eligible and -ineligible acute myocardial infarction-related cardiogenic shock (AMI-CS) patients in a nationwide Japanese registry.

A total of 3975 AMI-CS patients treated with Impella between 2020 and 2023 were identified from the J-PVAD registry. Patients were stratified into five groups: eligible STEMI-CS, non-eligible STEMI-CS, out-of-hospital cardiac arrest (OHCA), mechanical complications (MCs), and non-STEMI-CS (NSTEMI-CS). Eligible STEMI-CS was defined as STEMI-CS fulfilling all of the following: lactate ≥ 2.5 mmol/L, systolic blood pressure <100 mmHg or catecholamine use, left ventricular ejection fraction <45%, and shock onset to first Impella support ≤24 h. Thirty-day mortality, associated risk factors, and complications were examined across the five groups.

Eligible STEMI-CS accounted for 35.6% of all AMI-CS cases, with a 30-day mortality of 37.6%. Non-eligible STEMI-CS patients had lower mortality (27.6%), but it increased significantly with advanced age, renal dysfunction, veno-arterial extracorporeal membrane oxygenation use, ventricular arrhythmia, or sepsis. Thirty-day mortality was 51.3% in OHCA (63.4% without return of spontaneous circulation), 39.8% in MC, and 33.3% in NSTEMI-CS groups.

In this nationwide registry, one-third of AMI-CS patients treated with Impella met DanGer shock criteria. Outcomes in non-eligible subgroups were heterogeneous, highlighting the importance of individualized risk assessment in guiding Impella use in real-world practice.