Cardiogenic Shock, Myocardial Infarction (MI), Non-ST-Segment Elevation Myocardial Infarction (NSTEMI), ST-Segment Elevation Myocardial Infarction(STEMI)
Conditions
Keywords
Acute myocardial infarction, ST-segment elevation myocardial infarction, Non-ST-segment elevation myocardial infarction, Cardiogenic shock, Mechanical circulatory support, Microaxial flow pump, Impella CP, Percutaneous coronary intervention
Brief summary
PRIME-SHOCK is a prospective, single-center, open-label, randomized, superiority trial. Eligible participants with AMICS and a clinical decision to use Impella CP will be randomized in a 1:1 ratio before culprit-lesion PCI. The routine pre-PCI group will undergo Impella CP insertion immediately after allocation and before culprit-lesion PCI. The selective post-PCI group will undergo culprit-lesion PCI first; Impella CP will be inserted only if prespecified intra-procedural rescue criteria are met or shock persists or worsens after successful PCI. If all post-PCI recovery criteria are met, PCI will be concluded without Impella CP.
Detailed description
* Study Objectives: To determine whether routine pre-percutaneous coronary intervention (PCI) Impella CP reduces the composite of all-cause death within 30 days after randomization or refractory shock within 48 hours after index PCI compared with revascularization first and selective post-PCI Impella CP in patients with acute myocardial infarction-related cardiogenic shock (AMICS) for whom Impella CP support is planned. * Study Background: AMICS is among the most lethal complications of acute myocardial infarction (AMI). It occurs in approximately 5-10% of patients with AMI, and short-term mortality remains approximately 40-50% despite rapid reperfusion and advances in critical care. Early culprit-vessel revascularization has been central to AMICS care, yet shock and multiorgan failure frequently persist after technically successful PCI. Vasopressors and inotropes are often required to maintain blood pressure and organ perfusion, but high doses or prolonged use can increase myocardial oxygen demand, provoke arrhythmia, and worsen peripheral vasoconstriction. Routine mechanical circulatory support for unselected AMICS populations has not consistently improved outcomes. Impella CP is a percutaneous transvalvular microaxial flow pump inserted through the femoral artery. It transfers blood from the left ventricle to the ascending aorta, supporting systemic circulation while unloading the left ventricle and potentially reducing filling pressure, wall stress, and myocardial oxygen demand. The randomized DanGer-Shock (Danish Cardiogenic Shock) trial established a potential survival benefit in selected AMICS patients while reinforcing the need to optimize use and limit device-related harm. The 2025 American guideline for the management of acute coronary syndromes states that, in selected patients with ST-segment elevation myocardial infarction (STEMI) and severe or refractory cardiogenic shock, the use of a microaxial flow pump may be reasonable to reduce the risk of death. However, in the DanGer-Shock trial, randomization concerned the use of the Impella CP, whereas the timing of device insertion, before or after PCI, was neither randomized nor specified by the study protocol. Accordingly, the guideline also acknowledges that the preferred timing of Impella insertion remains unclear. Therefore, the results of DanGer-Shock alone do not establish the superiority of pre-PCI over post-PCI insertion, and a randomized trial directly comparing these two strategies is warranted. This study will randomly compare the clinical efficacy and safety of a routine pre-PCI Impella CP insertion strategy with a PCI-first strategy involving selective Impella CP insertion. It will determine whether the potential benefits of early left ventricular unloading and hemodynamic stabiliation outweigh the risks associated with pre-emptive device insertion in all patients, or whether restricting Impella CP use to patients with persistent shock after initial coronary revascularization can reduce unnecessary device use and related complications while providing comparable or superior clinical outcomes. This study has important clinical significance because it will address a key unresolved question following the DanGer-Shock trial, moving beyond "whether to use the Impella CP" to "in whom and when it should be used". By incorporating the potential benefit of avoiding device use in patients whose shock resolves with PCI alone, while simultaneously evaluating the risks of delaying circulatory support in those who require early mechanical support, this study is expected to provide a more individualized, evidence-based strategy for Impella CP use in patients with AMICS. \- Study Hypothesis: Routine pre-PCI Impella CP will reduce the composite of all-cause death within 30 days after randomization or refractory shock within 48 hours after index PCI compared with revascularization first and selective post-PCI Impella CP.
Interventions
PROCEDURERoutine pre-PCI Impella CP
In the PCI Impella CP group, Impella CP will be routinely inserted before culprit lesion PCI in patients with acute myocardial infarction-related cardiogenic shock.
PROCEDURESelective post-PCI Impella CP
The selective post-PCI Impella CP group will undergo culprit-lesion PCI first; Impella CP will be inserted only if prespecified intra-procedural rescue criteria are met or shock persists or worsens after successful PCI for culprit lesion. In the selective post-PCI group, immediate mechanical circulatory support will be instituted during PCI if any of the criteria are met. Impella CP is preferred when feasible. VA-ECMO may be initiated during resuscitation when Impella CP cannot be placed promptly or is insufficient. In the selective post-PCI group, successful culprit-lesion revascularization is done without shock progession, PCI will be concluded without Impella CP only when all of the criteria are met.
Sponsors
Chonnam National University Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
19 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Age ≥19 years old * Acute myocardial infarction with culprit lesion requiring urgent percutaneous coronary intervention * Cardiogenic shock before culprit lesion percutaneous coronary intervention * Left ventricular ejection fraction ≤40% * Patients with persistent signs of shock despite medical therapy who are scheduled to undergo Impella CP insertion * Shock onset to randomization ≤12 hours
Exclusion criteria
* Non-acute myocardial infarction-related shock * No clear culprit lesion * Mechanical complication of myocardial infarction * Predominant right ventricular or biventricular shock * Ongoing cardiopulmonary resuscitation at the time of screening * Refractory ventricular arrhythmia * Unwitnessed cardiac arrest without bystander cardiopulmonary resuscitation * Cardiopulmonary resuscitation duration \>45 minutes * Glasgow Coma Scale \<8 after return of spontaneous circulation * Contraindication to Impella CP use * Prior mechanical circulatory support before randomization * Active major bleeding or inability to receive anticoagulation or antiplatelet therapy required for percutaneous coronary intervention and Impella CP support * Life expectancy \<1 year
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Composite of all-cause death or refractory shock within 48 hours after index percutaneous coronary intervention | At 30 days after randomization |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Composite of all-cause death or refractory shock within 48 hours after index percutaneous coronary intervention | At 12 months after randomization | — |
| All-cause death | At 30 days and 12 months after randomization | — |
| Number of participants with refractory shock within 48 hours after index percutaneous coronary intervention (PCI), assessed using prespecified clinical, hemodynamic, and arterial lactate criteria | Within 48 hours after index percutaneous coronary intervention | Refractory shock is defined as any of: (1) rescue escalation to mechanical circulatory support beyond the randomized strategy, (2) acute cardiac arrest, or (3) persistent or worsening tissue hypoperfusion requiring at least one arterial lactate criterion AND at least one concurrent hemodynamic/organ-perfusion criterion. Lactate criteria: two consecutive increases at approximately 2-hour intervals, 24-hour lactate clearance \<40 percent with lactate ≥4 mmol/L at 24 hours, or persistent lactate ≥5 mmol/L during hours 24-48. Concurrent criteria: increasing vasopressor requirement, use of ≥2 vasoactive agents; persistent mean arterial pressure \<65 mm Hg, urine output \<0.5 mL/kg/h for ≥6 hours; cardiac power output \<0.6 W, or cardiac index \<2.2 L/min/m\^2. Protocol-concordant post-PCI Impella CP insertion in the selective group is not, by itself, rescue escalation. |
| Time from randomization to arterial lactate <2.0 mmol/L | At 30 days after randomization | — |
| 24-hour arterial lactate clearance | At 24 hours after randomization | — |
| Cardiac death | At 30 days and 12 months after randomization | — |
| Rate of ischemic or hemorrhagic stroke | At 30 days and 12 months after randomization | — |
| Rate of renal replacement therapy | At 30 days and 12 months after randomization | — |
| Rate of limb ischemia | At 30 days and 12 months after randomization | — |
| Rate of clinically significant Impella CP-related hemolysis | At hospital discharge (up to 30 days) | — |
| Major bleeding (Bleeding Academic Research Consortium [BARC] type 3 or 5 bleeding) | At 30 days and 12 months after randomization | — |
| Major vascular complications | At 30 days and 12 months after randomization | — |
| Sepsis or bloodstream infection | At 30 days and 12 months after randomization | — |
| Impella CP malfunction, malposition, or device-related cardiac or vascular injury | At hospital discharge (up to 30 days) | — |
| Rate of hospitalization for heart failure | At 12 months after randomization | — |
| Rate of stent thrombosis | At 30 days and 12 months after randomization | — |
Countries
South Korea
Contacts
CONTACTMin Chul Kim
PRINCIPAL_INVESTIGATORYoungkeun Ahn
Chonnam National University Hospital
Outcome results
None listed