Impella: pumps overview and access site management.

The Impella left ventricular support system consists of two main components: a family of different ventricular support catheters with a microaxial pump to be placed across the aortic valve and a single external controller which is connected to activate and control the pump function. Four Impella left ventricular support catheters are available: Impella 2.5, Impella CP, Impella 5.0 and Impella LD. Impella 2.5 and Impella CP are designed for percutaneous peripheral insertion, have respectively a 12F and 14F maximal diameter at the pump level and are capable of providing up to 2.5 and 4.1 liters per minute, respectively. Impella 5.0 and Impella LD have 21F maximal diameter at the pump level and are designed for surgical insertion through, respectively, a peripheral artery (femoral or axillary) or the aorta. The Impella CP or 5.0 are commonly selected for cardiogenic shock patients. The femoral approach represents the most adopted access site for percutaneous Impella insertion. Yet, it requires the presence of suitable aorto-iliac-femoral arterial axis for retrograde advancement of the Impella pump. The axillary artery is usually the main alternative approach for surgical insertion in the patients with unfavorable peripheral anatomy or for patients requiring prolonged assistance. When adopting Impella pumps, maximal attention should be paid to the access site management before, during and after cardiac assistance in order to minimize the risk of vascular complications.