Role of Impella in Cardiac Arrest Management
The Impella device can be considered as a rescue therapy for selected patients with cardiac arrest when conventional CPR is failing, particularly in settings where it can be implemented rapidly such as the catheterization laboratory or specialized cardiac arrest centers.
Device Overview and Classification
- The Impella is classified as a nondurable, percutaneous, continuous-flow, axial pump with an external controller that provides temporary mechanical circulatory support 1
- Different models are available with varying support capabilities:
Current Guideline Recommendations for Mechanical Support in Cardiac Arrest
- It may be reasonable to use extracorporeal cardiopulmonary resuscitation (ECPR) as a rescue treatment when initial therapy is failing for cardiac arrest that occurs during percutaneous coronary intervention (PCI) 3
- Mechanical CPR devices may be considered to provide chest compressions to patients in cardiac arrest during PCI 3
- Institutional guidelines should include appropriate candidate selection for mechanical support devices to ensure they are used as a bridge to recovery, surgery, transplant, or other device 3
- For pregnant women with cardiac arrest due to suspected pulmonary embolism, extracorporeal membrane oxygenation (ECMO) may be considered as an acceptable salvage therapy 3
Evidence for Impella in Cardiac Arrest
- Early initiation of mechanical circulatory support with Impella prior to PCI has been associated with improved hospital and 6-month survival in patients with post-cardiac arrest cardiogenic shock complicating acute myocardial infarction 4
- In a single-center study, patients who received Impella support before PCI showed higher survival rates (54.3% vs 30.4% at discharge) compared to those who received it after PCI 4
- The feasibility of Impella insertion during cardiac arrest has been demonstrated, with successful device placement reported in multiple studies 5, 2
- In one study comparing Impella to intra-aortic balloon pump (IABP) in post-cardiac arrest shock, survival rates without neurological sequelae were similar (23% vs 29.5%) 6
Clinical Scenarios Where Impella May Be Considered
- Cardiogenic shock following cardiac arrest, particularly after acute myocardial infarction 1, 4
- Refractory cardiac arrest with pulseless electrical activity presumed due to primary left ventricular failure 2
- During high-risk PCI when cardiac arrest occurs 1
- As a bridge to recovery when left ventricular function is expected to improve 3
Limitations and Complications
- In-hospital mortality remains high (86%) when Impella CP is placed during ongoing CPR 5
- Vascular complications are more common with Impella compared to IABP (9.8% vs 3.8%) 1
- Serious bleeding complications occur more frequently with Impella than with IABP (26% vs 9%) 6
- The device has maximum flow limitations that may be inadequate for patients with large body mass or severe cardiogenic shock 1
- Contraindicated in patients with left ventricular thrombus, severe aortic stenosis, severe peripheral artery disease, or aortic disease 1
Practical Considerations for Implementation
- Anticoagulation is required to prevent pump thrombosis:
- Initial unfractionated heparin bolus of 100 U/kg (up to 5000 U maximum) at the time of implantation 1
- Echocardiographic assessment is crucial for:
- For patients failing initial weaning attempts, consider longer support duration or transition to more durable mechanical circulatory support devices 1
Comparison with Other Mechanical Support Options
- Unlike IABP, Impella devices offer greater left ventricular support 1
- Compared to TandemHeart, Impella has a simpler design and implantation procedure 1
- VA-ECMO provides biventricular support but may require additional left ventricular venting, potentially using an Impella, to prevent left ventricular distension 1