From the Guidelines
Impella placement is recommended for patients with cardiogenic shock who require temporary mechanical circulatory support to improve cardiac output and end-organ perfusion, as supported by the most recent guidelines and studies, including those published in 2021 and 2022 1. The device should be considered when patients show signs of cardiogenic shock despite optimal medical therapy, including inotropes and vasopressors. Key considerations for Impella placement include:
- Left ventricular ejection fraction less than 25%
- Systolic blood pressure below 90 mmHg despite pharmacological support
- Evidence of end-organ hypoperfusion The Impella device should be inserted via the femoral artery using a modified Seldinger technique under fluoroscopic guidance, with proper positioning across the aortic valve confirmed by both fluoroscopy and echocardiography. Some important points to consider:
- The recommended duration of support is typically 3-7 days, though it can be extended based on clinical response
- During Impella support, patients require systemic anticoagulation with heparin to maintain an activated clotting time of 160-180 seconds to prevent thrombus formation
- Daily assessment of hemolysis markers, renal function, and limb perfusion is essential
- The device flow should be adjusted based on hemodynamic parameters, aiming for a cardiac index above 2.2 L/min/m² and mean arterial pressure above 65 mmHg Impella works by unloading the left ventricle and augmenting cardiac output, which reduces myocardial oxygen demand and improves coronary perfusion, potentially allowing for myocardial recovery in reversible conditions, as described in studies such as those published in Circulation in 2021 1. It is also important to consider the potential complications and limitations of Impella placement, including bleeding, thrombosis, and limb ischemia, as well as the need for careful patient selection and multidisciplinary team management, as highlighted in guidelines and studies from 2020 and 2022 1.
From the Research
Impella Placement Recommendations
The Impella device is a crucial tool in managing cardiogenic shock, and its placement is a critical aspect of treatment. The following are key points to consider:
- The Impella device is an axial flow pump that is placed across the aortic valve to unload the left ventricle by delivering non-pulsatile blood flow to the ascending aorta 2.
- The device is used for high-risk percutaneous coronary intervention and cardiogenic shock, and has been proven to be safe and potentially superior to other mechanical support devices in this setting 2.
- The management of the Impella device involves several key concepts, including device placement, repositioning, and weaning 3.
Technical Considerations
The technical specifications of the Impella device and its accompanying technology are important to consider:
- The Impella heart pumps are intravascular microaxial blood pumps that provide temporary mechanical circulatory support during high-risk percutaneous coronary intervention or in the treatment of cardiogenic shock 4.
- The device is implanted using a minimally invasive procedure, and its placement is typically guided by fluoroscopy or other imaging modalities.
Timing of Impella Implantation
The timing of Impella implantation is a critical factor in determining outcomes:
- Pre-procedural insertion of the Impella device has been associated with improved 1-year survival in patients with cardiogenic shock due to acute myocardial infarction treated with percutaneous coronary intervention (PCI) 5.
- Early Impella support has also been associated with a lower rate of the composite of mortality, re-hospitalization for heart failure, and need for left-ventricular assist device/heart transplantation at 1-year in patients undergoing high-risk PCI 5.
Outcomes of Surgical Impella Placement
Surgical Impella placement has been associated with several benefits, including: