For some patients, conventional treatments are inadequate to relieve the effects of heart failure. Under these circumstances, mechanical circulatory support is considered. There are now a variety of devices capable of pumping blood to restore circulation to vital organs, even temporarily replacing the function of the native heart. Once the patient is stabilized, procedures such as bypass surgery, stent insertion, and/or medications can be offered to assist the injured heart to recover. Alternatively, if damage to the heart is beyond repair, patients can be considered for heart transplantation or implantation of more permanent heart replacement pumps that can allow individuals to lead active and productive lives.
The Impella uses a miniaturized axial flow pump fitted onto a pigtail catheter to directly unload the left ventricle (as opposed to the left atrium) and deliver blood to the ascending aorta, simulating normal physiology. There are 2 available devices that provide either partial (Impella 2.5) or full (Impella 5.0) hemodynamic support, indicating maximal flow rates of ≈2.5 and 5.0 L/min, respectively. Although both the smaller Impella 2.5 and the larger Impella 5.0 are utilized in clinical practice, the smaller device typically dominates the clinical landscape because of its smaller profile and autonomous implantation by the interventional cardiologist.
The Impella device consists of a single pigtail 12F catheter with inflow positioned in the left ventricle, outflow in the ascending aorta, and an incorporated intravascular axial pump that can deliver up to 2.5 L/min of continuous flow.