Axial Flow Percutaneous Ventricular Assist Devices: Physiology, Procedural Considerations, and Clinical Applications-A State-of-the-Art Review.

Percutaneous microaxial flow pumps have become an important form of temporary mechanical circulatory support for patients with advanced cardiac dysfunction, particularly in cardiogenic shock and high-risk percutaneous coronary intervention. By actively unloading the ventricle, reducing end-diastolic pressure and myocardial oxygen demand, and supporting systemic and coronary perfusion, Impella devices offer distinct physiological advantages over passive support strategies. This state-of-the-art review summarizes the mechanisms of ventricular unloading, device characteristics, procedural considerations, monitoring requirements, complication management, and contemporary clinical applications of axial-flow percutaneous ventricular assist devices. Current evidence suggests that, in selected patients with infarct-related cardiogenic shock, early and protocolized Impella use may improve survival, although this benefit must be balanced against higher rates of bleeding, hemolysis, vascular injury, thrombosis, and device-related complications. In high-risk percutaneous coronary intervention, Impella may enhance procedural stability and facilitate more complete revascularization, but a definitive survival benefit remains unproven. Emerging applications include right ventricular support, biventricular support, postcardiotomy shock prevention, ventricular tachycardia ablation, and combined use with venoarterial extracorporeal membrane oxygenation. Despite expanding use, major uncertainties remain regarding optimal timing, patient selection, standardized anticoagulation and weaning protocols, cost-effectiveness, and generalizability beyond infarct-related shock. Further randomized trials, registry-based analyses, and technological refinements are needed to define which patients benefit most while minimizing complications.